# Longer Lens or Crop Sensor



## photoflyer (Jan 21, 2018)

I need longer reach.  So in the coming year I will either get a longer lens or a crop senor body to go with the glass I have.  I am curious what all of you think about the trade-offs for each strategy. 

A little background.  I have a 6D mark II and the 70-200 2.8  L USM II with the 2x teleconverter.  I shoot sports inside and out and would like to have longer reach for wildlife photography. 

My perception is that the crop sensor would be the less expensive option but a longer lens on a full frame is technically better.   I am concerned about noise at high ISO on the likes of the 7D m II or the 80D  (assuming those are the best Canon crop sensor options).

Thoughts?


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## Peeb (Jan 21, 2018)

I'd go crop body so that you have more reach AND a backup.


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## tirediron (Jan 21, 2018)

Just to clarify:  A crop sensor does NOT give you 'more reach'.  The crop factor simply refers to the field of view, and NOT any extra magnification.  In other words, on a crops sensor, a 100mm lens is considered to a 150mm lens, however what this means is that when you mount a 100mm lens on a crop-sensor body, it gives you a field of view similar to that of a 150mm lens on a full-frame body.  It does not magnify it.


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## qmr55 (Jan 21, 2018)

tirediron said:


> Just to clarify:  A crop sensor does NOT give you 'more reach'.  The crop factor simply refers to the field of view, and NOT any extra magnification.  In other words, on a crops sensor, a 100mm lens is considered to a 150mm lens, however what this means is that when you mount a 100mm lens on a crop-sensor body, it gives you a field of view similar to that of a 150mm lens on a full-frame body.  It does not magnify it.



That's good info...I never knew that to be honest. Good to know.


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## Alexr25 (Jan 22, 2018)

qmr55 said:


> tirediron said:
> 
> 
> > Just to clarify:  A crop sensor does NOT give you 'more reach'.  The crop factor simply refers to the field of view, and NOT any extra magnification.  In other words, on a crops sensor, a 100mm lens is considered to a 150mm lens, however what this means is that when you mount a 100mm lens on a crop-sensor body, it gives you a field of view similar to that of a 150mm lens on a full-frame body.  It does not magnify it.
> ...


That's also very misleading info!
The sensor size combined with the focal lens determine the image angle of  view and angle of view is the thing that gives a tele lens its tele properties. While it is true that sensor size does not in any way affect the lens focal length it does affect the image angle of view and hence the apparent magnification of the subject. A 200mm lens on a crop body will give you the same angle of view as a 300mm lens on a full frame body.


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## jaomul (Jan 22, 2018)

The focal length was standardized off a 35mm sensor, so in theory if you use that standard a crop sensor doesn't give extra reach but magnifies it.

In real use it's kind of bs. I think it would be simpler if a standard is used to just give it's equivalent on different type cameras but my opinion on this is rather insignificant 

If I was in your position I'd likely buy the 7d2 second hand and probably try get something like the sigma 150-600. As long as your wildlife shots are in reasonable light you should be good.

You'd have a backup, and if light was a little lower you could use it on the 6d, just compromising a bit of reach for image quality


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## khakoo (Jan 22, 2018)

Alexr25 said:


> qmr55 said:
> 
> 
> > tirediron said:
> ...



I'm sorry, but it's your post that's misleading. There's a lot more to the topic but what tirediron posted was correct in clearing up a misconception about "crop factor". The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens. A longer focal length both magnifies the scene _and_ narrows the field of view proportionally, but decreasing sensor area only reduces field of view. Sensor design _can_ influence the size of recorded details by virtue of its pixel count. A 24MP crop sensor produces a larger image than a 20MP full frame, for example, so if "reach" is a key requirement then that's one way to increase it. However, as we know, more pixels means smaller photosites, trading off light sensitivity and therefore increasing noise compared to a larger sensor of the same generation.


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## petrochemist (Jan 22, 2018)

If he crop body you're considering has the same pixel density as your existing camera then the only gain is having a backup camera, as the images would be just like you cropping your existing images. However APSC bodies often have a higher pixel density so there may be a real gain with the right one.

Getting a good lens that longer than your existing combo (140-400mm f/5.6 with TC fitted) will be expensive & heavy especially if you want that impressive speed.  There are a few 150-600 zooms available now (I gather the Tamron is well regarded) which might suit, but I don't think they'll like the TC. Perhaps renting one for a weekend will give you a feel for how it performs.


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## Overread (Jan 22, 2018)

My view is glass first (lenses) unless you want to change your format (sensor/film) size; then you change the camera first and then the lens.

However it seems that the only real feature you want is greater reach and magnification of the subject. Whilst a crop sensor "sort of" gives you that (and whilst you can crop your fullframe shots I appreciate that getting it closer to right in-camera is more fun and rewarding for most photographers); I would think that it might be better to save your money and save up for that far more expensive longer lens. 

However that hinges on how long it would take you to save up. I think you want to sit down and work out what lens would fit your needs best and then calculate roughly how long it would take to actually save for it. If you start talking years and years to save up then a new camera body makes sense now; if you're talking a year or months then mayhap save. Don't forget that the 7DMII is getting older and there are rumours of a new version coming out or at least being announced this year (granted these are very rough rumours, but that camera is gettnig old now and as it is canons crop sensor flagship it makes sense that an update should be coming)


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## jcdeboever (Jan 22, 2018)

If I was into birding / wildlife seriously, I would be looking at things like prime lenses, 400, 500 and use a TC on those as opposed to a TC on a zoom. Additionally, in the camera body, I would look at things that have fast auto focus tracking and acquisition. If I had the OP's current setup, and the money, I'd be looking for a 400 or 500 L prime and a TC. If not into it seriously or limited budget, than the Tamron 150-600 g2.


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## Braineack (Jan 22, 2018)

tirediron said:


> Just to clarify: A crop sensor does NOT give you 'more reach'. The crop factor simply refers to the field of view, and NOT any extra magnification. In other words, on a crops sensor, a 100mm lens is considered to a 150mm lens, however what this means is that when you mount a 100mm lens on a crop-sensor body, it gives you a field of view similar to that of a 150mm lens on a full-frame body. It does not magnify it.



he didn't say extra magnification or focal length, he said extra reach.

what if we defined "reach" as a narrower FOV (as it always is) and not focal length or magnification (not that anyone actually does).  now what?

I'm going to quote you

"The crop factor simply refers to the field of view"

now:

"The reach factor simply refers to the field of view"

:shock:


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## Braineack (Jan 22, 2018)

khakoo said:


> The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens.



The advantage is a myth?!   the advantage is real.

what complete disingenuous drivel.

I'm sorry, but cropping a 24MP FF image to fill the frame with a bird and ending up with a 10MP image is _*not the same*_ as an uncropped 24MP aps-c image that required no cropping to fill the frame with a bird.


How about we go about this a different way:

You have two cameras; one crop and one ff.  Both with the same lens.

there's a bird on a post in front of you, you look through each viewfinder and decide to shoot with the crop sensor because the bird fills the frame -- even though we are using the same lens.

what do you call this effect?

we know it's not reach, cause reach is a myth.  so what should ever photographer in the world start calling it?






It's an illusion, Michael.


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## Alexr25 (Jan 22, 2018)

khakoo said:


> I'm sorry, but it's your post that's misleading. There's a lot more to the topic but what tirediron posted was correct in clearing up a misconception about "crop factor". The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens. A longer focal length both magnifies the scene _and_ narrows the field of view proportionally, but decreasing sensor area only reduces field of view. Sensor design _can_ influence the size of recorded details by virtue of its pixel count.


So what exactly do mean by this mystical magical term "REACH" and how do you quantify it, or more to the point how does "reach" differ from angle/field of view?
Yes I know you can crop down any image to produce the same results as using a longer lens but  that will be at the expense of picture quality, if you take that approach to its logical conclusion you can use a wide angle lens for everything and then just crop to suit. You'll have great reach but shame about the quality!


khakoo said:


> A 24MP crop sensor produces a larger image than a 20MP full frame, for example, so if "reach" is a key requirement then that's one way to increase it. However, as we know, more pixels means smaller photosites, trading off light sensitivity and therefore increasing noise compared to a larger sensor of the same generation.


A 24MP crop sensor will produce a 24MP image and a 20MP FF will produce a 20MP image, that is why they are called 24MP and 20MP respectively however this tells me absolutely nothing about "reach".
To my mind "reach" is synonymous with field of view and as such it is solely determined by a combination of lens focal length and sensor dimensions.


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## tirediron (Jan 22, 2018)

Alexr25 said:


> That's also very misleading info!  The sensor size combined with the focal lens determine the image angle of  view and angle of view is the thing that gives a tele lens its tele properties. While it is true that sensor size does not in any way affect the lens focal length it does affect the image angle of view and hence the apparent magnification of the subject. A 200mm lens on a crop body will give you the same angle of view as a 300mm lens on a full frame body.


If that isn't what I said, it's certainly what I meant to.  The point being, that a crop-sensor camera does not give you any "free magnification".


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## tirediron (Jan 22, 2018)

Braineack said:


> tirediron said:
> 
> 
> > Just to clarify: A crop sensor does NOT give you 'more reach'. The crop factor simply refers to the field of view, and NOT any extra magnification. In other words, on a crops sensor, a 100mm lens is considered to a 150mm lens, however what this means is that when you mount a 100mm lens on a crop-sensor body, it gives you a field of view similar to that of a 150mm lens on a full-frame body. It does not magnify it.
> ...


  Erhmmm... how'zat again?


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## Braineack (Jan 22, 2018)

tirediron said:


> Braineack said:
> 
> 
> > tirediron said:
> ...




define reach.


*true statement:*
all things being equal crop sensors give you extra reach.

*false statement:*
all things being equal crop sensors give you extra focal length.

*false statement:*
all things being equal crop sensors give you extra magnification.


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## tirediron (Jan 22, 2018)

Braineack said:


> ...The advantage is a myth?!   the advantage is real...
> 
> what complete disingenuous drivel.
> 
> ...



"Illusion" is a good word.  I can live with that.  

My initial post may not have been the most accurate; I was simply attempting to refute the common misconception that a lens of XXX mm when placed on a crop-sensor camera will give you the same results as one of [approximately] one third less on a full frame camera.  For the sake of simple math, it's commonly believed that placing a 100mm lens on an APS-C / DX body will give you a result similar to that of a 150mm lens on an FF body.  That is simply not the case.  

The various definitions of 'reach' notwithstanding, and assuming both bodies had the same pixel count on the sensors, then what you will get when you put your 100mm lens on a crop-sensor camera is an image which has a field of view equivalent to that of a 150mm lens used on a full-frame camera.  Yes, it fills the frame on the crop-sensor camera just like on the FF body.  Why?  *BECAUSE IT"S A SMALLER FRICK'IN FRAME!*


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## Alexr25 (Jan 22, 2018)

tirediron said:


> My initial post may not have been the most accurate; I was simply attempting to refute the common misconception that a lens of XXX mm when placed on a crop-sensor camera will give you the same results as one of [approximately] one third less on a full frame camera. For the sake of simple math, it's commonly believed that placing a 100mm lens on an APS-C / DX body will give you a result similar to that of a 150mm lens on an FF body. That is simply not the case.


Actually IT IS THE CASE, at least it is in terms of field of view which is the major factor in determining lens choice. Depth of field will be different but generally its the field of view that is the important parameter.


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## Braineack (Jan 22, 2018)

tirediron said:


> The various definitions of 'reach' notwithstanding, and assuming both bodies had the same pixel count on the sensors, then what you will get when you put your 100mm lens on a crop-sensor camera is an image which has a field of view equivalent to that of a 150mm lens used on a full-frame camera.  Yes, it fills the frame on the crop-sensor camera just like on the FF body.  Why?  *BECAUSE IT"S A SMALLER FRICK'IN FRAME!*



and thus extra reach.   why argue this?


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## tirediron (Jan 22, 2018)

Okay........   I guess I genuinely don't understand "reach".


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## astroNikon (Jan 22, 2018)

photoflyer said:


> I need longer reach.  So in the coming year I will either get a longer lens or a crop senor body to go with the glass I have.  I am curious what all of you think about the trade-offs for each strategy.
> 
> A little background.  I have a 6D mark II and the 70-200 2.8  L USM II with the 2x teleconverter.  I shoot sports inside and out and would like to have longer reach for wildlife photography.
> 
> ...


Back to the OPs original question.

I have BOTH, for totally, but the same reasons.
D750 (24mp) and D7200 (24mp)  ( had a D500 - 20mp, and previous a D7000 - 16mp)

FF - portraiture photography
FF - attach to my telescope to get larger swaths of sky
CROP - attached to my telescope to get smaller segments of sky

SPORTS - this is dependent upon a few factors.  For instance on a Crop D7200 I want to have a wide focal length.  Say I use my 80-200.  It's actually FOV 120-300.  Good for the long end @300, but horrible for the short end @120 if I'm near the side line.  If I'm in the stands it's okay; of course the FullFrame is 80 on the short end great for the close sidelines but many time not enough reach.  

But then I can use a 70-300 on the FullFrame for the same effects on the sideline and cover more focal range than the Crop.  And 300mm actually is quite good for a full size football/soccer field. ... for a 1 lens setup.  If you use a 2 camera setup I'd use my 24-85 on FF and 80-200 on Crop.

Now let's throw a monkey wrench into that concept.
If you are shooting in the evening or lower light situations the FF will have the advantage.  My D500 I shot at an evening soccer game under the Bright LED lights.  It did "okay" on the edge of getting bad.  The FF had no problems.    For the extra $$ the D500 was I swapped to a D7200 instead as it was a little less in lower light but at that point the FF with a good 70-300 is the better option anyways ... unless you're after FPS.

Aircraft/Birding - using my 150-600 the Crop definitely has the advantage there of 900mm FOV unless it's early in the morning, or later in the evening or heavily overcast .. ie, the lower light issue.

So the answer is ... it depends.  In perfect lighting the crop will have certain advantages.

Of course a teleconverter can mess with that formula too.


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## BananaRepublic (Jan 22, 2018)

I watched a few youtube vids on this and it took me a while to get past what the stooges and the  ivory tower experts were saying but I think I have a vague understanding now. I was fine with the field of view concept before hand but one guy spoke about multiply your lens aperture by the sensor crop factor.  Is the aperature concept an important factor in this thread , ie, reach/magnification or is it a seperate issue.


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## Overread (Jan 22, 2018)

This is one of those topics where you can take it three ways

1) The simplistic way - angle of view comparisons only and a casual understanding - perfectly fine for 99.9% of photographers and photography

2) Full physics understanding of what is going on

3) A half and  half approach that will often make little to no sense. This is because you'll be adding in real physics elements to simplified descriptions that "carry the point" but are factually wrong. 

The aperture aspect is one such area where this gets rather convoluted and confusing. Suffice it to say that crop factor will have an influence on your depth of field (as a result of the circle of confusion changing because of the format size change); however by and large its a negligible difference. The only photographers that ever tend to notice are macro photographers.

Also whilst the depth of field changes the aperture isn't changing - it remains the same. You know this to be true because otherwise things like external light-meters wouldn't work


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## Braineack (Jan 22, 2018)

tirediron said:


> Okay........   I guess I genuinely don't understand "reach".



while I think it's fair we all understand the real physics involved and why and what's going on here; I like to define "reach" as the ability to _natively _fill the frame with the subject.

example: I've been seeing some awesome birding images out of a 300mm lens with the 4/3 E-M5. At 300mm, that thing has a lot more reach than 300mm on my D800...

you can't say that "reach is a myth" because it's real.  Call it  "optical cropping" or what have you, but to say it's not real is disingenuous.  I can't crop a 36MP image down by a factor of 2 and end up with 40MP -- the math don't add up.


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## john.margetts (Jan 22, 2018)

tirediron said:


> Okay........   I guess I genuinely don't understand "reach".


It's a bit like sharpness that people bat on about. There is no property of either a lens or an image that you can define as sharpness - sharpness is an amalgam of various properties rather than a property itself. I think 'reach' is another amalgam - you can define the various properties that contribute to the non-property 'reach' but never actually really define 'reach' itself.


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## Derrel (Jan 22, 2018)

Braineack said:


> tirediron said:
> 
> 
> > Okay........   I guess I genuinely don't understand "reach".
> ...



I agree with this..the Nikon D2x which has an APS-C sensor with a 1.5x FOV factor and my 400mm lens, I get top speed of 5.0 frames per second, and an X by Y field of view at a baseball game. Using that same camera and sensor in high-speed crop mode, the FOV factor becomes 2.0, and the frame-per-second rate goes up to 8.2 f.p.s., and the lens frames EVEN-more tightly!

The same thing can be done on newer Nikon d-slr cameras, like for example the D610 or D800 full-frame bodies can shoot in what Nikon calls FX (full-frame) format, or also in DX format. Using the _same lens_, like say an 85mm or a 105mm, when the camera is shooting in full-frame mode, the field of view is relatively wide; when the camera is switched to DX mode, the field of view of the 85mm or 105mm lens is reduced commensurately.

Anyway, to the OP: I'd look into the 150-600mm zoom lens as an affordable, long, stabilized lens for birds. Glass first!


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## BananaRepublic (Jan 23, 2018)

On a APS - C  with a DX lens does the FOV calculation apply or is only valid  it for FX lenes on cropped sensor bodys


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## astroNikon (Jan 23, 2018)

BananaRepublic said:


> On a APS - C  with a DX lens does the FOV calculation apply or is only valid  it for FX lenes on cropped sensor bodys


A 50mm DX lens is the same as a 50mm FX lens in focal length.  Just that the DX lens has less diameter glass to produce less diameter image as the DX sensor is smaller than an FX sensor.  This manufacturing allows a less costly lens, smaller and lighter.

but to calculate true FOV one uses (for Nikon DX) 1.5x the lens focal length irregardless if it's a DX specific or FX lens.

So on a DX crop body use 1.5x the focal length .. whether 35mm, 50mm, 85mm, etc.  irregardless if the lens was a specific DX or FX made lens to cover a larger or smaller sensor image circle.


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## Derrel (Jan 23, 2018)

BananaRepublic said:


> On a APS - C  with a DX lens does the FOV calculation apply or is only valid  it for FX lenes on cropped sensor bodys



SAME FOV, on a DX- or APS-C camerta, when using either a DX lens or a lens that covers full-frame...the DX-Nikkor 35mm f/1.8 AF-S gives the same field of view as say, the 35mm f/2 AF-D Nikkor, when used on a DX camera.


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## photoflyer (Jan 23, 2018)

Very informative  (and spirited) dialogue.   Clearly fast glass is the best and much more expensive solution.  

Having a good second body is a plus though.  

I am told Sony APS-C sensors are very good at high ISO and that there is an adapter that would enable it to work with L series Canon glass.  Anyone have experience or thoughts on this?


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## ac12 (Jan 23, 2018)

If you need to reach out, 

My first option would be for a longer lens

But at a certain point, you will not be able to afford the $$,$$$ for a  LONG  lens.  So there is a practical/affordable limit to how long a lens you can get.

Manual Focus (MF) alternative:  Because the $1,400 cost of a 500mm AF lens (Nikon 200-500mm) was way beyond my limit, I went with a used MF Nikon 500mm mirror lens.  The used MF 500mm lens was 10% of the cost of the Nikon 200-500m zoom lens.  I was not going to pay $1,400 for a lens that I would use only very occasionally, like less than 1/2% of the time.  I would rather put that $ into a 70-200 f/4, which I would use much more.  Your priorities may be different than mine.

Con:  I cannot follow focus on FAST moving subjects.  My hit rate shooting tennis was less than 20%.  So MF is fine for stationary or slow moving subjects, but not for fast moving subjects.
BTW, I have a MF 800mm mirror lens, for when the 500mm lens is not long enough.  


If you want a  LONG lens, there are options to put a dslr onto small astronomical reflector telescopes.  

You can get some seriously LONG glass here.  

Con are:  Manual focus.  The telescope and mounts are BULKY and not simple to transport or setup.  The mounts are NOT made to track FAST moving subjects, like flying birds or surfers or similar.  Some of these astronomical teles are somewhat fragile, compared to a SLR lens.  Like a mirror lens, the aperture is fixed, so you expose by ISO level and shutter speed.


My second option would be a crop factor body, in place of the FF body.  

Or a FF body with a crop function.

In my case, since I currently use a DX crop body, #2 is NA, as I am already here.

Use a tele-converter.  

The problem is you need a GOOD tele-converter $$$ to maintain image quality.  Not a cheap $30 one, which will degrade the image quality.

There are some lens/tele-converter matched pairs, and if so that pair is what you should get.  Don't substitute.

Tele-converters will cost you f-stops.  Once you go beyond f/5.6 or 8, some AF do not work, it is too dark to function and it may be too dark to manually focus.


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## petrochemist (Jan 24, 2018)

A great summary @ac12 
One additional thing to remember with teleconverters is even the best ones magnify any flaws in the main lens. For good results you need expensive lenses in front of them 

I've arranged my astro scope to mount on a heavy weight normal tripod (Manfrotto 058 with a fluid head). In tests diffraction had a significant effect with the higher magnification options, but prime focus worked pretty well on MFT. Still a complicated & heavy set up but usable where you have plenty of time to set up.

MF shots of moving subjects are possible usually the result of focusing ahead & then waiting for the subject to come into focus.  Though when the objects are far enough away this isn't needed - I had no real problems shooting power boat racing through a 1000mm telescope.

I've also gone the mirror lens route. My 600mm f8 isn't practical to handhold on MFT (1200mm equiv FOV) but with a focal reducer coupled up (900mm FOV and an extra stop of light) handholding is possible when braced.
 The same lens is usable on APSC too.


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## ac12 (Jan 24, 2018)

@pertrochemist,
I've handheld the 500 mirror on my D7200, and it worked OK. 
And you are correct, if you can brace yourself, you can hand hold it.

But for me, hand holding is not practical for any length of time, like shooting an event.  As I get tired, I get less steady.
For tennis, I put the rig onto a gimbal mount on my tripod.  That gimbal makes it sooo much easier to track a moving subject than with the 3-way head.  And it takes care of the weight and stability issue.  But a gimbal on a medium/heavy tripod is heavy and bulky to transport.  Mine has to go into a cart to move, I'm too old to carry all that gear.


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## tokaji michael (Jan 24, 2018)

I think that crop sensor is clear winner: longer lenses are more expensive than standard telephotos, crop sensors are cheaper than full frames so save your $$$,. And, don't forget that more element and glass will mean less sharpness.


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## astroNikon (Jan 24, 2018)

I've had the Nikon 500mm Reflex MF lens and also a Celestron 1,000mm focus ring reflex lens.  As mentioned you can hand hold it if you practice a lot.  FYI, I use telescopes a lot.  My main scope is 3,054mm and I have smaller ones.

But with AF there are lower cost alternatives.  I sold my Nikon 500mm Reflex MF and went to a Sigma 150-500mm lens.  It's a pretty good lens for the price point.  Now you can get them for under $500, even down to $270 just checking eBay.  I then upgraded to the Tamron 150-600 lens and have that now.

For you, since you want a better option for Wildlife I think a MF lens makes it very difficult as the subject can be totally unpredictable.  I've shot aircraft at 9+ miles away on my telescopes but it's easy to determine it's flight path for focusing.  But wildlife .. which way and when will it move and how fast; it's too unpredictable ??   I think going with a longer AF lens will definitely help initially.  The one example Sigma 150-500 is going to help a lot on your FF camera.  Then later on you can add a Crop body to it.


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## BananaRepublic (Jan 24, 2018)

photoflyer said:


> Very informative  (and spirited) dialogue.   Clearly fast glass is the best and much more expensive solution.
> 
> Having a good second body is a plus though.
> 
> I am told Sony APS-C sensors are very good at high ISO and that there is an adapter that would enable it to work with L series Canon glass.  Anyone have experience or thoughts on this?



To the best of my knowledge sony are contracted to make the sensors for every camera manufacture except canon.


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## khakoo (Jan 24, 2018)

Braineack said:


> khakoo said:
> 
> 
> > The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens.
> ...



Wow. Okay, let's try to clear some of the water you've clouded, shall we?

Asserting with such condescending language does not make anything so. On the contrary, your own remarks here ably demonstrate the properties of which you falsely accuse mine. Your obnoxious expression would be excessive even if I had been incorrect. In light of the fact that you are actually in error, about the topic and my post, it's inexcusable.



Braineack said:


> I'm sorry, but cropping a 24MP FF image to fill the frame with a bird and ending up with a 10MP image is _*not the same*_ as an uncropped 24MP aps-c image that required no cropping to fill the frame with a bird.



That is not what I said, and resorting to such juvenile tactics only reveals your desperation to cling to a delusion. I did point out that a crop sensor would produce a larger image *if it possessed a higher pixel count*, but that is not the point of contention here and you know it. The claim was that the reduced field of view of a smaller sensor is an equivalent gain to increased magnification, which it is not. If a full-frame and crop sensor *of equal pixel density*, are used to shoot the same scene, centred on the same point, at the same focal-plane distance, through the same lens, at the same focal length and focussed distance, the crop sensor will merely record *a smaller portion of that captured by the full-frame*. A higher resolution sensor of *any* format will produce a larger image, but this is not an inherent property of sensor size.



Braineack said:


> How about we go about this a different way:
> 
> You have two cameras; one crop and one ff.  Both with the same lens.
> 
> ...



In your example, the bird fills the frame because the *frame* is smaller, not because the image is enlarged. What should we start calling it? How about "reduced field of view"? I think people do generally mean "magnification" when they refer to "reach" in the context of photography, although the term still seems in quite casual use and perhaps yet to be settled. If your definition were to become the accepted one it would be of no value, and likely to mislead novices. This is why the term "crop sensor" was adopted, not "telesensor" or something of that sort, because the frame-filling effect of a smaller sensor is only due to reduced field of view. Why would you promote this as an imaging advantage, except to contort the meaning to conform to your own misapprehension? You are simply adopting the self-serving semantic ploy of Carroll's Humpty Dumpty.


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## Braineack (Jan 24, 2018)

> That is not what I said, and resorting to such juvenile tactics only reveals your desperation to cling to a delusion.



directly debating a topic is not juvenile.

you said and I QUOTE: "The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens."

I gave a clear example disproving how it's not the same:

"Cropping a 24MP FF image to fill the frame with a bird and ending up with a ~10MP image is _*not the same*_ as an uncropped 24MP aps-c image that required no cropping to fill the frame with a bird."

in that sentence you even admit there's some sort of real phenomenon happening, but the crop sensor is *NOT* cropping the image, it's capturing the image at 100%. So again, it's different.

you cannot deny that the same lens on a smaller sensor results in a narrow FOV.  that's a 100% real reach advantage.

If you want to create the same image on a FF as a APS-C sized sensor, uncropped, 100% native resolution, you need a longer lens because a 200mm lens on a FF body, just doesn't quite have the reach as a 200mm lens on a APS-C sensor.





khakoo said:


> In your example, the bird fills the frame because the *frame* is smaller, not because the image is enlarged.


so? this is irrelevant.  it's not about the how.

but youre admitting there's a difference.



> This is why the term "crop sensor" was adopted, not "telesensor" or something of that sort, because the frame-filling effect of a smaller sensor is only due to reduced field of view.



so? again, this is irrelevant.  I know how a crop sensor works, this is not the argument.

and a 4/3 sensor is called micro 4/3 because it's "micro" and 4:3  what's your point? does it not crop the image?



> Why would you promote this as an imaging advantage, except to contort the meaning to conform to your own misapprehension?



1. it* is *an advantage.
2. I have no mistaken belief. you're fooling yourself.

When someone says "youll get more height with these shoes" in terms of basketball

Are they taking about the ability to jump, or physically being taller in them.  I'm going with the former.


----------



## ClickAddict (Jan 24, 2018)

khakoo said:


> ........... If a full-frame and crop sensor *of equal pixel density*, ..............



Isn't the pixel density of a Crop much higher than a FF which makes your assertion here sort of prove your argument wrong?  Or are you attempting to base your argument on the fact an individual is asking to compare a 20MP FF vs a 12MP crop for example numbers?  Because most people would tend to think you would be comparing 20MP FF to 20MP Crops (example)  when asking about which has better reach.  

The idea of better reach for me is how far away can I get from subject and maintain a "minimum" quality (in terms of pixels captured and this would depend on usage planned on final print of course) of that desired subject (bird covering whole frame for instance)   I'm not going to discuss better low light and such unless that is also a part of the question.   If someone asks which is better for "Reach", a FF or crop, I'm not going to be comparing a FF or crops from 20 years ago to the other models of today.  I'm not going to compare the top of the line FF vs the cheapest entry level crop.  If they both start off at 20MP and you have to throw out a bunch of that data in your FF to get the same image (Bird filling frame) than the answer is pretty obvious.


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## BananaRepublic (Jan 25, 2018)

My Nuclear button is bigger than yours, and it works.


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## SuzukiGS750EZ (Feb 23, 2018)

I can tell you that in happy wth what i can do with my 80d and 150-600 g2 tamron...


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## photoflyer (Feb 24, 2018)

SuzukiGS750EZ said:


> I can tell you that in happy wth what i can do with my 80d and 150-600 g2 tamron...



Good to know.  I have heard good things about the 80D - in fact only good reports.    I think I am going to wait for the replacement for the 7D mark ii (rumor has it the mark iii will be out this spring/summer)  and then have a look at the  Tamron 150-600 g2 as the next step after that.    Your combo sounds like a great way to go.


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## Cortian (Feb 24, 2018)

photoflyer said:


> Good to know.  I have heard good things about the 80D - in fact only good reports.    I think I am going to wait for the replacement for the 7D mark ii (rumor has it the mark iii will be out this spring/summer)...


*Good*, cuz I have my eye on the 7D Mk II 



photoflyer said:


> ...  and then have a look at the  Tamron 150-600 g2 as the next step after that.    Your combo sounds like a great way to go.


Y'know what I'd _really_ like to put on a 7D Mk. <whatever>?  A Canon EF 400mm f/4 DO IS II USM.  But at $7,000 new, that's not very likely gonna happen


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## snowbear (Feb 24, 2018)

Photoflyer: Can your FF shoot in crop mode using the FF lenses?  If so, try that initially, and see if it gets you the results you are looking for.  It seems to me that a menu selection is a whole lot faster and cheaper than picking the wrong path.

Both of these are with a 28-85 at 50mm.  The first is FX mode, the second is DX mode; all other settings are the same.  Please excuse the soft focus, I shot them through a screen door.


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## photoflyer (Feb 24, 2018)

snowbear said:


> Can your FF shoot in crop mode using the FF lenses? If so, try that initially, and see if it gets you the results you are looking for. It seems to me that a menu selection is a whole lot faster and cheaper than picking the wrong path.



Interesting question.  I do not believe so (it is a 6D Mark II).  Maybe someone else knows.  I have studied the manual ad not seen that option.

The other reason to get a crop sensor is to have a second body in addition to the extra "reach" it provides and the reason to wait for the 7D mark iii is to get the latest technology though the 80D and the 7D mark ii look compelling.  I'm not in a hurry...yet.


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## john.margetts (Feb 25, 2018)

snowbear said:


> Photoflyer: Can your FF shoot in crop mode using the FF lenses?


Not on a Canon. There is no need as the 'DX' lenses (EF-S in Canon speak) will not fit on a full frame camera.


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## BananaRepublic (Feb 25, 2018)

photoflyer said:


> addition to the extra "reach"



extra reach is a marketing ploy, did you not read the thread.


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## snowbear (Feb 25, 2018)

john.margetts said:


> snowbear said:
> 
> 
> > Photoflyer: Can your FF shoot in crop mode using the FF lenses?
> ...


Ah, I think I remember reading that earlier.


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## photoflyer (Feb 25, 2018)

BananaRepublic said:


> extra reach is a marketing ploy, did you not read the thread.



Yes, I started it.  I think we all know what we want to achieve when we use a given lens on a crop sensor camera versus a full frame.  While I would like to have a 400 mm prime I cannot justify the 5k+ for the L series glass.  I need another body so I will get the best Canon crop sensor I can and use my 70-200mm 2.8 USM mII it. (I also have the 2x teleconverter).  Not as good as a prime on full frame but gets me another body  and close to 400mm 2.8 without spending more than twice as much.  As far as the semantics, I will leave them to others who have much more technical knowledge than I.


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## Braineack (Feb 26, 2018)

espresso2x said:


> Cropping an image to be pseudo 500mm isnt yielding the same definition as a native 500mm lens, whether for fx or dx.



what if you don't have to crop the DX image to appear as 500mm native FX?


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## BananaRepublic (Feb 26, 2018)

photoflyer said:


> BananaRepublic said:
> 
> 
> > extra reach is a marketing ploy, did you not read the thread.
> ...



A 2.8 becomes a 4.48 when you factor in the crop on a canon which is 1.6


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## photoflyer (Feb 26, 2018)

BananaRepublic said:


> A 2.8 becomes a 4.48 when you factor in the crop on a canon which is 1.6



I am not sure I understand.  I just put the 70-200 2.8 on a T5 I have and it shows f2.8.


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## Overread (Feb 26, 2018)

BananaRepublic said:


> A 2.8 becomes a 4.48 when you factor in the crop on a canon which is 1.6



I'd be VERY careful how you phrase some statements to avoid causing confusion.

The aperture in terms of exposure is the same no matter the camera body behind a lens. f2.8 is always f2.8 in exposure terms. This is a proven and well known bit of info that we all know without realising - because external light meters do work for any format (sensor) size and yet never require the sensor/film size to be entered in.

Now in terms of depth of field you are correct, the difference in depth of field between a 1.5 or 1.6 crop camera and a 35mm is roughly similar to around 1 stop in aperture. The full frame camera will have the lesser amount of depth of field.

An extreme way to also show this is if you use a mobile phone camera, where the sensor is tiny. In those you can easily see that the photos often have  very large depth of field; indeed its often very hard to get background blurring with such a tiny sensor.

The other end of the extreme is medium format cameras which offer far more background blurring effect, again because the depth of field for the larger sensor/film is so much greater.


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## john.margetts (Feb 26, 2018)

espresso2x said:


> Nah Overread you are wrong. Sorry. Try it: fx body and dx body, same lens, aperture priority. Faster shutter speed on the fx than dx. As i say also, Pentacon 4/50 wide open on fx gathers f/2 speed.


Absolutely not. The whole point of stating apertures as a ratio is that a given aperture ratio allows the same amount of light through regardless of lens focal length and sensor size.

If you think about it, the light has to go through the lens before it hits the sensor - it cannot 'know' before hand what sensor it is going to reach or if it is going to reach a sensor at all.

I have used various sensor sizes over 45 odd years and in a given light condition, all lenses at a given aperture ratio (f/number) require the same shutter speed. My hand held light meter would not (could not) work otherwise.

Sent from my A1-840 using Tapatalk


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## espresso2x (Feb 26, 2018)

You are right. Overread is correct. I just ran a test and the speeds are identical in both cases. I admit im mistaken and deleted the post.


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## john.margetts (Feb 26, 2018)

espresso2x said:


> Vignetting is where the edge of the lens is slower than the centre.


Again, absolutely not. 

First, the edge of the image is not formed by the edge of the lens. All parts of the lens form all parts of the image.

Second, vignetting is caused by 'stretching' a spherical image to fit onto a flat surface. This is also why the edge of the image is less sharp than the centre.

Sent from my A1-840 using Tapatalk


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## Braineack (Feb 26, 2018)

espresso2x said:


> Braineack said:
> 
> 
> > espresso2x said:
> ...




A 300mm FX lens on a DX camera, would appear exactly like shooting a 450mm lens on a FX camera.

So if you only had a 300mm, and you wanted more reach, you'd obviously shoot with it on the DX body.

If you say used a D750 with 24MP, and the 300mm, you'd have to crop the image down to appear like 450mm -- you'd have to crop it down to ~10.3MP.

If you say used a D610 with 24MP, and the 300mm, you'd have a full 24MP on an image with the same FOV as a 450mm on a FX.


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## Braineack (Feb 26, 2018)

Overread said:


> BananaRepublic said:
> 
> 
> > A 2.8 becomes a 4.48 when you factor in the crop on a canon which is 1.6
> ...



this.

a 70-200 2.8 shot at 100mm and f/2.8 on a micro 4/3 (2x crop), would produce an image that appears like a FX shooting at 200mm and f/5.6 -- all other things being equal.


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## Overread (Feb 26, 2018)

The difference in angle of view is exaggerated at shorter focal lengths. It's why we quickly go from 300 to 400 to 500 whilst at the shorter end there's a marked difference between 18mm and 16mm. 

There is likely some difference between focal lengths in terms of the distortion and such between long focal lengths, but chances are the differences are more minor. The kind you have to really look for and the kind very quickly and easily removed by "lens corrections" clicks in editing software (eg Lightroom). So such differences might be very tricky to spot.

So for all extents and purposes most people compare the "reach" or magnification that long focal length lenses give rather than other aspects.


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## BananaRepublic (Feb 27, 2018)

I do like throwing a ferret in a chicken house at times ( metaphorically) 

But to follow on there is allot of confusing information been put out there take the clip below how much of that is true and how much of it is him trying to flog his brand.


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## Overread (Feb 27, 2018)

From what I've seen Tony both gets things wrong, gets the wrong end of the stick and presents things in away which is counter intuitive to getting the point across when he does get it right.

Also he seriously needs to change his shirt! All those moire patterns as the digital video recorder fails to work with the dense pattern - gah a nightmare


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## Braineack (Feb 27, 2018)

Tony has good instructional videos, but his technical videos suck.  he gives false "facts" on purpose

his formula for multiply the aperture by the crop factor is correct -- but he presents it in a way that's purposefully confusing and controversial.

all he has to do is caveat the statement by saying "in terms of DOF", but he doesn't.  Because he knows people will see it, link it, and be like "this guy is crazy, sensor size has nothing to do with exposure rules".  and he gets more $$$ from the views.


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## BananaRepublic (Feb 27, 2018)

Braineack said:


> Tony has good instructional videos, but his technical videos suck.  he gives false "facts" on purpose
> 
> his formula for multiply the aperture by the crop factor is correct -- but he presents it in a way that's purposefully confusing and controversial.
> 
> all he has to do is caveat the statement by saying "in terms of DOF", but he doesn't.  Because he knows people will see it, link it, and be like "this guy is crazy, sensor size has nothing to do with exposure rules".  and he gets more $$$ from the views.



I suppose its a deliberate thing just to get website hits up ergo more money from sponsors and book sales

Similar to saying 
*Reach is Real.*


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## Braineack (Feb 27, 2018)

I've thoroughly explained why reach *is* real in this thread.  It's not a similar statement.  Saying "reach is real" is not a trick, it's not misleading, and it's not false.  "Cropping" an image by using a smaller sensor is _much_ different than cropping an image after it has been created and it allows a shorter lens to be used on a smaller sensor to achieve the same framing as a longer lens on a larger sensor -- with 100% of pixels used to create the image.

if you crop a 300mm image taken with a FX to look like the same subject taken by your buddy standing next to you with the same lens on a DX body -- your image will look like ****, his won't.

which is much different than stating: "a 2.8 lens on a DX will behave like a 4.6" -- which is only true in the regards of DOF.  He's completely ignoring the effects on exposure with aperture, since the same aperture value will still collect the same amount of light, not less light by the crop factor.

I'm also not selling anything, or misleading anyone, or playing with semantics, plus I hand out my wisdom for free.


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## BananaRepublic (Feb 28, 2018)

Braineack said:


> I've thoroughly explained why reach *is* real in this thread.  It's not a similar statement.  Saying "reach is real" is not a trick, it's not misleading, and it's not false.  "Cropping" an image by using a smaller sensor is _much_ different than cropping an image after it has been created and it allows a shorter lens to be used on a smaller sensor to achieve the same framing as a longer lens on a larger sensor -- with 100% of pixels used to create the image.
> 
> if you crop a 300mm image taken with a FX to look like the same subject taken by your buddy standing next to you with the same lens on a DX body -- your image will look like ****, his won't.
> 
> ...



Ok jees 

I was not comparing you to him I merely said, all be it without going into much explanation as I thought the remark would be understood, that his method of ham fisted explanation is most likely intentionally confusing in order to create more interest and hype about his brand and therefore sell more of his  stuff.     

Furthermore allot of crud is sold nowadays on the basis of one liners and soundbites and click bait and your statement that "reach is real" is very like what confidence men churn out in order to line there pockets.

FYI i am not calling you a con man and if you cant see that well then thats on you. 

(End Transmission)


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## Braineack (Feb 28, 2018)

I consider people who deny reach is real, flat-earthers


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## chuasam (Feb 28, 2018)

How much do you want to spend? Also, fieldcraft counts for a LOT with bird and animal photography.


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## photoflyer (Feb 28, 2018)

chuasam said:


> How much do you want to spend? Also, fieldcraft counts for a LOT with bird and animal photography.



Very true.  Sometimes we lose sight of the art (and craft) and caught up in the technology.  I think this has become even more of a trap with the advent of digital photography.


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## BananaRepublic (Mar 1, 2018)

Braineack said:


> I consider people who deny reach is real, flat-earthers


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## Ferrarimx5 (Mar 4, 2018)

BananaRepublic said:


> Braineack said:
> 
> 
> > I consider people who deny reach is real, flat-earthers



A light hearted perspective, not to be taken seriously.

"Reach is real":    Perhaps this statement is nothing more than a two dimensional misdirection, same as our flat earth is a two dimensional misdirection. (being a reflection of our ignorance both are a challenge to our perceived reality). (Click bait)..  When you expand into the three dimensional world, your new depth of field not only changes your perspective, it provides a completely different perception of new, expanded facts to sift.  Can "reach" be measured in megapixels? Depends not only on your frame of reference, (on the density of the crop you are harvesting, or the quality of the sensor), but also on the chipset that is attached.   (Or not)...

In reality, we are all mislead by marketing and only by discussing the real world applications (and the results there-of), are we ever going to be satisfied with our understanding.

Most of us understand that reach is real and the earth is not flat..   Our problem is in properly defining "Reach" without blurring the subject with an unrelated discussion about the amount of resolution.

Here is one perspective:


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## Braineack (Mar 5, 2018)

Ferrarimx5 said:


> In reality, we are all mislead by marketing and only by discussing the real world applications (and the results there-of), are we ever going to be satisfied with our understanding.



Put a 300mm lens on your 24mp crop sensor body -- and have the reach -- to achieve a picture like having a 450mm on your full frame 24mp camera.

real world application.  it's as simple as that. no misdirection.


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## Ferrarimx5 (Mar 5, 2018)

Real world...   
Put a 300mm lens on your 24mp crop sensor body -- and have the reach -- to achieve a picture like having a 450mm on your full frame 36mp camera.   But not quite the same f-stop and not the same DOF...      if you compare this to a 24mp full frame your resolution will suffer,...    minor points but still important misdirection...

real world application.  it's as simple as that. no misdirecti


Braineack said:


> Ferrarimx5 said:
> 
> 
> > In reality, we are all mislead by marketing and only by discussing the real world applications (and the results there-of), are we ever going to be satisfied with our understanding.
> ...


----------



## Braineack (Mar 5, 2018)

*REAL WORLD:*

Put a Xmm lens on your Ymp crop sensor body -- and have the reach -- to achieve [framing] a picture like having a (X * crop factor)mm on your full frame Ymp camera.

Both images will having equal framing and image size.

Put a Xmm lens on your Ymp crop sensor body -- and have more reach -- to achieve a picture longer/closer/more zoomed in than having the same Xmm lens on your full frame Ymp camera.

the crop sensor will have an image with a larger subject while maintaining the same image size.  Meaning you would have to physically crop MPs out of the FF image to achieve similar framing.


----------



## Ferrarimx5 (Mar 5, 2018)

Yes.        Reach ( as defined) is independent of Depth of field.   And I agree with this definition.   This is a worthwhile discussion and helps us understand the complexity of the differences between full frame and cropped. The F-stop being just one of the variables.


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## BrentC (Mar 5, 2018)

Ferrarimx5 said:


> But not quite the same f-stop and not the same DOF...      if you compare this to a 24mp full frame your resolution will suffer,...    minor points but still important misdirection...





Ferrarimx5 said:


> Yes.        Reach ( as defined) is independent of Depth of field.   And I agree with this definition.   This is a worthwhile discussion and helps us understand the complexity of the differences between full frame and cropped. The F-stop being just one of the variables.



F-stop on crop or FF is the exact same.  The DoF may be different at same f-stop but f2.8 on a crop lets in the same light as f2.8 on FF.  And larger DoF does not mean image quality will suffer.


----------



## Ferrarimx5 (Mar 5, 2018)

BrentC, You said:
[/QUOTE] F-stop on crop or FF is the exact same.  The DoF may be different at same f-stop but f2.8 on a crop lets in the same light as f2.8 on FF.  And larger DoF does not mean image quality will suffer.[/QUOTE]

Did you not watch the video above titled:   "Crop Factor, Why you multiply the aperture by the crop factor?"

Perhaps you do not agree with the math as stated in that YouTube video.

The phrase you used "Exactly the same"  means it is equal to, it does not mean like or about, it means equal to in all ways possible, it means exactly.   If what you are stating is true, then this is how we have gotten misdirected and derailed in our conversation.

We are attempting to define the term "Reach"  

What is the reach?  
Does a 200 zoom on a full frame camera represent being  4 times closer to a subject compared to using a 50mm lens?    The reach could then be described as 4X.. 
This would not be the same math we would use for a cropped sensor.  All parts of the equation have to be considered.

Watch the video above and see if what Tony Northrup is saying is true.   

Tony has persuaded me with his scientific approach and his logical method of explanation.  If you are right then we are misunderstanding each other because I am persuaded by the math as Tony has presented it


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## Derrel (Mar 5, 2018)

One issue is that reach is often calculated without regard to the DOF or the background blur; the highest-end sports and wildlife/nature shooters often tend to prefer the greater background blur of the big-glass lenses like 300/2.8 and 400/2.8 and 500mm and 600mm f/4 super-teles on larger-sensor cameras, as opposed to the slightly more in-focus backgrounds that come with crop-sensor cameras and commensurately shorter lenses.

Depth of field and Background Blur are two different things; *background blur* depends on the absolute, physical WIDTH of the lens aperture. A wider aperture, a physically w_i_d_e_r aperture, causes more background blur than a narrower aperture. This is why a 300mm f/2.8 or a 200mm f/2, has such a huge degree of background blurring on a half-body portrait when either lens is set to f/2.8. However, do a half-body portrait with a 50mm lens, from close range even, at f/2.8, and the degree of background blurring is substantially LESS.

The issue of saying "identical images" from a crop-sensor with one lens length and a full-frame sensor with a shorter lens length is NOT accurate...the images are similar, but not identical, with regard to both DOF and background blurring...the degree of background blurring is NOT identical, and that's what Northrup and others are trying to get people to realize.

Bottom line: if you want to totally,totally,totally separate the subject from the background, the larger the capture format, the easier that is to do. Because of the lenses that are offered for sale, there comes a time when the larger sensors have an advantage in achieving large-sized animals or birds or athletes on-sensor, and very,very,very de-focused backgrounds. There are also many times when it is literally impossible for the small-sensor user to open-up the lens an additional two stops or whatever, to achieve parity with the way existing,real-world lenses for full-frame cameras achieve; there do not exist any 300mm f/1.4 lenses, nor 600mm f/2 lenses,etc..


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## BrentC (Mar 5, 2018)

F-stop on crop or FF is the exact same.  The DoF may be different at same f-stop but f2.8 on a crop lets in the same light as f2.8 on FF.  And larger DoF does not mean image quality will suffer.[/QUOTE]

Did you not watch the video above on Crop Factor:  Why you multiply the aperture by the crop factor?

Perhaps you do not agree with the math as stated in that YouTube video. 

The phrase you used "Exactly the same"  means it is equal to, it does not mean like or about, it means equal to.   If what you are stating is true, then this is how we have gotten misdirected and derailed in our conversation.  We are attempting to define the term "Reach"   What is the reach?   is a 200 zoom on a full frame camera represent being  4 times closer to a subject than if you were using a 50mm lens?    The reach would be 4X..  This is not the same math for a cropped sensor.  All parts of the equation have to be considered.  Watch the video above and see if what Tony Northrup is saying is true   Tony has persuaded me with his scientific approach and his logical method of explanation.  If you are right then we are misunderstanding each other because I am persuaded by the math as Tony has presented it[/QUOTE]


F-stop is f-stop.   An f-stop of a lens is based on how much light can pass through the lens, regardless of sensor size or fl.   This is fact.  Whether on crop sensor or not this does not change.  Your saying it does which is false.   DoF is based on the fl, f-stop and sensor size.  Fl and f-stop does not change, the only variable is the sensor size which determines the D0F.  

'Reach', or whatever you want to call it, is how a far off subject appears in the frame.   A subject in frame from a 300mm lens on m43 will be the exact same as on a 150mm lens on FF.  This is fact.

The only thing that is going effect IQ of image is how good the lens is, megapixels and the sensor itself.


----------



## Ferrarimx5 (Mar 5, 2018)

I agree with you.   Although the total light gathered by a full frame sensor is quite a bit more than the light gathered by a cropped sensor.   I do now agree with you that the aperture is the same F-Stop and does not change or close when you put it on a Cropped sensor camera..  Point well made.


----------



## Ysarex (Mar 5, 2018)

Ferrarimx5 said:


> BrentC, You said:
> [/QUOTE} F-stop on crop or FF is the exact same.  The DoF may be different at same f-stop but f2.8 on a crop lets in the same light as f2.8 on FF.  And larger DoF does not mean image quality will suffer.





Ferrarimx5 said:


> Did you not watch the video above titled:   "Crop Factor, Why you multiply the aperture by the crop factor?"
> 
> Perhaps you do not agree with the math as stated in that YouTube video.
> 
> ...



I've been reluctant to get caught up in this one, but what the heck. *Braineack has this one solid: reach is real.*

Tony's language is really sloppy and he says all kind of things that just make you cringe. A 45mm f/1.8 on a M4/3 body is a 45mm f/1.8. It is not and it does not magically become a 90mm f/2.8. It will never be a 90mm f/2.8 for as long as you use it. That video is responsible for a lot of confusion.

Brent is correct that f/X = f/X no matter the lens and camera system. F stop values normalize exposure over all lenses and camera systems. That's the point and that's why we have them. And so if a scene is correctly exposed at ISO 400 with a shutter speed of 1/250 sec and f stop value of f/8 on a 4x5 view camera using a 300mm f/5.6 Sironar then that scene is likewise correctly exposed at ISO 400 with a shutter speed of 1/250 sec and f/stop value of f/8 on a M4/3 Olympus using a 45mm f/1.8. *F/8 as an exposure value is f/8!* 

Different format cameras produce different results based on the size of the recording media -- it's simple. When we compare the same photo between cameras with different format sizes, DOF increases as the recording format gets smaller. In the digital world larger format sensors have a low-light advantage over smaller format sensors. So this is easy: When looking at the issue of "reach" and comparing two different format cameras DOF and low-light performance should be considered to the extent they're a factor. In the case of FX versus DX sensor cameras used for images that the OP noted (sports and wildlife) I'd rank the DOF variance and low light performance pretty low in making a decision. Note that (and Tony did mention this) there's a tendency for those two factors, DOF and high ISO performance, to somewhat cancel each other. More DOF from the smaller format camera means you may be able to use a wider aperture which means you may be able to use a lower ISO. I'd be more inclined to make my decision based on this:






Joe


----------



## Ferrarimx5 (Mar 5, 2018)

Joe,
Now that totally makes sense!
Well worded, focused and seems to be the best way to view this subject.
I agree that the most cost effective and sensible answer to the OP's question would be to get a modern cropped camera with a high quality lens.

In my case this meant ordering the 7DM2 with the EF 70-300mm (F-4 to 5.6) IS II USM lens.
This investment will cost me less than two grand total and will meet 90 percent of my immediate wildlife needs.

Many would suggest upgrading to a better quality Canon L series lens and this is also a good option. Wish I could afford to add one to the mix,  In my opinion  the 7DM2 will be a very serviceable way of meeting the OP's need for more reach with a camera that will provide many other desirable options.

Now, there is nothing wrong with the 80D, but my choice was made because of the faster, more accurate high speed focus and the 10 frames per second captures..   So many great choices out there for lenses, but the fast quality of the new 70-300 Nano IS II fit my budget..  As with all things, budget was my deciding factor.

a 2x teleconverter seems to offer great benefits, but also adds some compromise.  Premium glass is expensive.. Hard to make a total commitment without accepting some compromises.

I entered this thread with the thought of adding some humor  with a light hearted comment to the seven pages of banter, but ended up really digging deeper into the decisions I made this week on upping my game.  (My 60D decided to no longer turn on when I flipped the switch)  Hoping the 7DM2 lives up to the Marketing Hype.  Regardless, there is always a better tool and always a lot more to learn.  The biggest improvements are found in gaining experience using the tools we have been allocated.


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## photoflyer (Mar 6, 2018)

Ferrarimx5 said:


> Hoping the 7DM2 lives up to the Marketing Hype.



Make sure you let us know.  I have only heard good reports about the 7D M II.


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## Ferrarimx5 (Mar 8, 2018)

photoflyer said:


> Ferrarimx5 said:
> 
> 
> > Hoping the 7DM2 lives up to the Marketing Hype.
> ...


Hmm..  Perhaps I should give you some examples, but my 60D overall took noticeably better pictures.  I am hoping this is just a learning curve kind of difference, but I've felt a bit disappointed..  I might load a few examples in another thread and let you decide.   Different day, different types of shots, same lens, but just not the same feeling..


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