# So You Wanna See the Difference Between Full Frame and Cropped Sensors?



## kundalini (Aug 4, 2010)

Thinking about going full frame, but are confused the difference this 'crop factor' is compared to full frame? Seeing one image of this or that doesn't really resonate? You want / need side-by-side comparisons? 

Do you have an aversion to pink? If not....... carry on. Winston is more than happy to help out if he's in front of the camera.

This is a v-e-r-y non-scientific lab results test. It was done on a Sunday afternoon, I had nowhere to go, and no chance of driving.......... getting the picture? 

I originally did a two shot of DX versus FX using a 50mm f/1.8 lens (hey.... I shoot Nikon and they're acronyms we know). DX is the cropped body (D300 here) and FX is the full frame body (D700 in this case). My thinking is that most people have or can obtain a 50mm focal length. A discussiion elsewhere brought up the 35mm vs 50mm debate as well. This made sense and I did a reshoot..... on a Sunday afternoon, I had nowhere to go, and no chance of driving.......... getting the picture? 

The setup is:
Lenses:  Nikkor 35mm f/2 and Nikkor 50mm f/1.8
Camera to subject = 28" (except as noted)
Subject to background = 60"
F/5.6
1/250s
ISO200
EV = -.0.7
Shot at ~15:30, conditions were bright sun to sun behind thick clouds, black cover used on diffuser to block sun
Flash at 45° camera left in 24" soft box at 45° above, flash at 135° camera right with 8" snoot feathered to hit the very back of his head ~24" above.

I also used a CPL but may not have turned it exactly the same between lens changes.


*....................................DX 35mm.....................................................................FX F5mm...........................*
*







*




*....................................DX 50mm.....................................................................FX 50mm...........................*









Here's what you paid admission for..............


*....................................DX 35mm.....................................................................FX 50mm...........................*










*....................................DX 35mm..................................FX 35mm (recomposed for 16" camera to subject).....*
*






*



Now I'm getting confused.................. See if this helps. I shot some other stuff with thesae combos. The dots are starting to get difficult to connect.


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## Derrel (Aug 4, 2010)

Excellent work for a Sunday afternoon, with nowhere to go, and no chance of driving..........

Super post!


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## MrBarney (Aug 5, 2010)

Very nice, although I expected the results you show for 1 and 2 (differing subject sizes) and 4 (more perspective distortion due to FOV change).  It's #3 that I'm spending the time peering at. 

I *think* that the bush behind Winston (?!) is thrown more out of focus with FX.  Of course, it might be my eyes!  Can anyone confirm this?  Is there anything else I'm missing.


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## Robin Usagani (Aug 5, 2010)

nice job!


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## supraman215 (Aug 5, 2010)

The 2 photos after "Here's what you paid admission for......" are exactly what I was looking for. They illustrate the difference in the quality, you can see in his bow. I also see the difference between 50 and 52mm. 35*1.6=52

THANKS!


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## kundalini (Aug 5, 2010)

Thought you might also like to see how each sensor handles the out of focus background. The physical size of each pixel (not just the sensor) is larger for a full frame. I would expect better performance.

The DX images are at 100% crop. In order to get a similar framed size, I had to go to 150% on the FX images. Even more pixel peeping. 



*.......................................DX 35mm......................................................*







*.......................................FX 35mm......................................................*












*.......................................DX 50mm......................................................*







*.......................................FX 50mm......................................................*






I thnk it's proven that the bokeh is much better handeled by a full frame sensor.​


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## shmne (Aug 5, 2010)

Now that is what I wanted to see! Close up goodness. 

It is amazing how much better a full frame sensor with better pixels can capture an image as opposed to the crop frame. This just furthers my drive to purchase a full frame and some L series glass


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## Steve01 (Aug 5, 2010)

:thumbup: Nice explanation and presentation.


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## arios23 (Aug 5, 2010)

BRAVO, BRAVO!!


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## Markw (Sep 11, 2010)

I dont mean to pull this out of the dust, but I think it deserves another look-through by most and I cant see the second post worth of photos! :er:

Mark


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## Higgs Boson (Jan 5, 2011)

This seals it for me, my next body will be a 5DM(III?) and not a 7D as long as it gets the good AF, etc....

Great thread.


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## 2WheelPhoto (Nov 7, 2011)

Wow @ the FF performance.


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## Big Mike (Nov 7, 2011)

Also, check THIS out.


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## rateeg (Nov 7, 2011)

i love you


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## Trever1t (Nov 7, 2011)

I missed this. It's actually amazing the differences between the D300 and D700 with relatively the same pixel count (D700 slightly less than D300) It's not just the bokeh, it's the total tonal depth that's improved as shown by your samples. Well done!


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## DiskoJoe (Nov 7, 2011)

Did you really need a thread for this? Most of us know this without needing picture references.


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## Big Mike (Nov 7, 2011)

> Did you really need a thread for this? Most of us know this without needing picture references.


I think it's a great thread because while most people know that full frame is better...many of them don't necessarily understand the how & why.  And I'd venture that there are a lot of people who are at the stage of deciding whether to buy a full frame or a high end APS-C.


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## kundalini (Nov 7, 2011)

DiskoJoe said:


> Did you really need a thread for this?


Nope, just had a Sunday afternoon to kill.



DiskoJoe said:


> Most of us know this without needing picture references.


Good to know this information is already well known by most of you.  Thanks for looking.


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## MTVision (Nov 7, 2011)

kundalini said:
			
		

> Nope, just had a Sunday afternoon to kill.
> 
> Good to know this information is already well known by most of you.  Thanks for looking.



I didn't know anything about full frame or crop sensor a few months ago. I've heard full frame was better but I never knew why. I honestly didn't think there would be that much of a difference. So thank you for taking the time to show me and everyone else! 
I guarantee this information isn't well known by everyone on this forum.


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## TenaciousTins (Nov 7, 2011)

And I have yet to know what full frame and sensor even are. Good to see the comparisons although I don't yet understand them!


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## Overread (Nov 7, 2011)

Big Mike said:


> > Did you really need a thread for this? Most of us know this without needing picture references.
> 
> 
> I think it's a great thread because while most people know that full frame is better...many of them don't necessarily understand the how & why.



Your former crop sensor brethren weep at your conversion to the fullframe world and your disguarding of your crop past!


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## Big Mike (Nov 8, 2011)

Overread said:


> Big Mike said:
> 
> 
> > > Did you really need a thread for this? Most of us know this without needing picture references.
> ...


I'm not getting rid of my 20Ds any time soon.  Although, they won't get much use anymore.  I did some quick shots yesterday with a 20D....I could barely read the menu....the LCD screen is so small.  
I've seen some 40Ds for sale for great prices....that is actually pretty tempting.


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## 2WheelPhoto (Nov 8, 2011)

D700/grip ordered


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## Carny (Feb 29, 2012)

Can you post side by side comparisons of the dx and the fx cropped to match?


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## xj0hnx (Feb 29, 2012)

Carny said:


> Can you post side by side comparisons of the dx and the fx cropped to match?


Right click > Save Picture As > Name them the same but with a 1 after the DX and 2 after the FF (monkey1, monkey2, etc ) then you can compare them more easily in Windows, and even zoom in for better detail.


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## digital flower (Feb 29, 2012)

Nice monkey. Looks like a rare species


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## Carny (Feb 29, 2012)

xj0hnx said:


> Carny said:
> 
> 
> > Can you post side by side comparisons of the dx and the fx cropped to match?
> ...



It says his photos aren't ok to edit, so that's why I didn't


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## Carny (Feb 29, 2012)

Also, these are jpegs so they really won't give me the info I'm looking for.  I just really want to know what the difference is between a DX image and an FX image that has been cropped


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## Robin Usagani (Feb 29, 2012)

Carny said:


> Also, these are jpegs so they really won't give me the info I'm looking for.  I just really want to know what the difference is between a DX image and an FX image that has been cropped



It should be identical.  IQ may be a little different.  The background, size of subject, size of circle confusion should be the same after you crop the FX image.


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## Carny (Feb 29, 2012)

Schwettylens said:


> Carny said:
> 
> 
> > Also, these are jpegs so they really won't give me the info I'm looking for.  I just really want to know what the difference is between a DX image and an FX image that has been cropped
> ...



IQ is exactly what I'm wanting to see.  I'm wanting to see exactly what the difference is between the two, and much of this extra "reach" you really get with a crop body.


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## Robin Usagani (Feb 29, 2012)

The extra reach is just cropping down the FX to about 2/3 the height and width.


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## Dominantly (Feb 29, 2012)

Very nice.


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## Patrice (Feb 29, 2012)

Carny said:


> Schwettylens said:
> 
> 
> > Carny said:
> ...



Just as Schwetty says above and as has been explained in the other "crop" thread, there is no such thing as "extra reach" from a crop sensor camera. What you get is a smaller fraction of the image the lens projects, then you enlarge it more to fill the display space or print medium. A crop sensor camera does not magically turn your 135 mm lens, or any lens,  into anything longer. As for the quality of the resulting image there is nothing intrinsically better in a full frame sensor and also nothing intrinsically worst in a crop sensor. The quality is dependant on many variables which have been combined by the various manufactures so as to optimize the imaging process for the desired results for each particular camera model.


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## Patrice (Feb 29, 2012)

Double post.


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## Carny (Feb 29, 2012)

Schwettylens said:


> The extra reach is just cropping down the FX to about 2/3 the height and width.



 I understand the difference between the two as far as FOV and all of that.  I really do.  That is not what I'm asking but is the answer I keep getting.



Patrice said:


> Carny said:
> 
> 
> > Schwettylens said:
> ...




Yes, the difference between FF and crop has been explained.  Beat to death really.  BUT, no one has really answered what I've been asking.  Some have come really close, but then go right back to the same claim.  For instance, in the other thread:



enzodm said:


> Carny said:
> 
> 
> > I think everyone would agree that the 1Dx has better IQ than the 7D. I haven't actually looked at any 1Dx photos, but I think that is a safe assumption. So this sort of makes the argument for crop body counter-intuitive. Overall, the 1D wins. But, if you pick any section of a 1Dx image that is the same size as a 7D image, then the 7D image is better than just that section.
> ...



enzodm seems to really know what he is talking about, and he used the "more reach" argument.

Meanwhile, Schwetty is saying he thinks the FX cropped would be better than the DX.

They contradict each other, and I'm trying to figure out what is actually correct.  I know the specific camera comes into play as well.

So, why does anybody use crop over FF?

What advantage does a crop have? (please don't say reach, lol)

Why don't birders, wildlifers, whoever, use a FF and then just crop the shot?


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## tirediron (Feb 29, 2012)

Carny said:


> [So, why does anybody use crop over FF?
> 
> What advantage does a crop have?


Cost.


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## Overread (Feb 29, 2012)

Cost - reach (getting it right in camera does help) - generally superior AF (esp outside the 1D line for canon) - generally faster frames per second - generally a slightly larger buffer.

Also remember that the cropping against capturing the shot on a native crop sensor camera is always going to be a battle of end outputs and also resolutions and MP ratings of the cameras compared. So whilst cropping on some fullframe bodies will give you about the same or better than some cropped sensor the reverse might also be  true.


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## Carny (Feb 29, 2012)

Overread said:


> Cost - reach (getting it right in camera does help) - generally superior AF (esp outside the 1D line for canon) - generally faster frames per second - generally a slightly larger buffer.




SEE!!! ^


How does it help, exactly?



It's looking like "reach" is just going to be one of those things that is technically incorrect but I'll just have to get used to because everyone uses it.


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## tirediron (Feb 29, 2012)

Each time you see the word 'reach' in relation to crop sensors, exchange it for the term 'field of view'.  In other words, a 50mm lens on a crop-body has the equivalent field of view of a 75mm lens on a FF body.


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## Overread (Feb 29, 2012)

Yeps just like everyone calls exposure value exposure  
But honestly the concept of more "reach" is pretty much what one sees through the viewfinder - even if its not accurate its a fairly simple concept to understand and explains away the real world effect one sees. Whilst its clearly been used (abused?) by marketing its going to stick around I suspect. 

Asides which it helps because many people like to compose within the frame that they see. Furthermore a slightly larger view of the subject helps for focusing purposes and placement of the AF point.


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## jamesbjenkins (Feb 29, 2012)

Simple, direct and to the point.  Excellent teaching thread with practical application for all skill levels.  Hat's off to ya, sir.


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## Carny (Feb 29, 2012)

tirediron said:


> Each time you see the word 'reach' in relation to crop sensors, exchange it for the term 'field of view'.  In other words, a 50mm lens on a crop-body has the equivalent field of view of a 75mm lens on a FF body.



I'm just trying to figure out if there is any real advantage to it, or just a misnomer/marketing ploy.


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## Robin Usagani (Feb 29, 2012)

OMG... OK I am going to explain it to you for the LAST time.  If you still dont get it... I wont make any more replies.  Just for conversation sake lets say you have 2 cameras.  One is 24MP FX, one is 24MP DX.  Both cameras will produce 6000x4000 (24mp) JPEG.  You are standing from one location using same PRIME lens on both cameras.  You shoot a house from this location with the DX camera and you have the PERFECT composition.  You are happy with the result.  The printer you are using use 300 dpi.  You can print high quality print of 20" x 13.33" (resolution divided by 300).  NOW you use your FX.  It shoots wider than the DX.  You take the shot on the same spot.  You decided to crop your 6000x4000 jpeg to have the same look as your DX photo.  That means you crop the sides and you end up having 4000x2667 resolution JPEG.  That means wiht the same printer you can only have high quality print up to 13.33"x8.9".  

The conclusion is.......  if you print 13.33"x8.9" OR SMALLER... without a doubt the FX print will look better while DX is slightly worse (more noise) but not that much worse if we shoot it at low ISO.  If you print something bigger than that, the DX will continue to print decent up to 20"x13.33" while the FX will need to use software interpolation to be able to print at 300 dpi that big.  You will start seeing pixelation if you dont interpolate it with a software.  If you interpolate, it is just guessing/adding pixels so your photo wont look as good.    

Do you get it or not get it now?


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## Overread (Feb 29, 2012)

Carny said:


> tirediron said:
> 
> 
> > Each time you see the word 'reach' in relation to crop sensors, exchange it for the term 'field of view'.  In other words, a 50mm lens on a crop-body has the equivalent field of view of a 75mm lens on a FF body.
> ...



Think of it just like a different angle of view. You'd get the same thing if you compared fullframe cameras (35mm film) to medium format - the med format would give you a far wider angle of view, shallower depths of field possible etc... In the end its not so much a case of chasing the ultimate resolution, but about chasing the camera bodies that fit your budget and also suit your shooting requirements. 
If you shoot wildlife a weather sealed, fast AF camera body is a need and if you can't afford a 1D then something like a 50D or 7D is an ideal option. On the other hand if you shoot more studio and have less need of those features then the 5DMII (or 5D) is an option - that said if you shoot wildlife and use a 5DMII (or 5D) you'll have weaker AF - not impossible to use in any means, but weaker than the better AF of the 7D. 
So you pick the tool that offers the best advantages for your shooting practice (and often people seriously into photography will end up with more than one camera for different applications).


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## Carny (Feb 29, 2012)

Schwettylens said:


> OMG... OK I am going to explain it to you for the LAST time.  If you still dont get it... I wont make any more replies.  Just for conversation sake lets say you have 2 cameras.  One is 24MP FX, one is 24MP DX.  Both cameras will produce 6000x4000 (24mp) JPEG.  You are standing from one location using same PRIME lens on both cameras.  You shoot a house from this location with the DX camera and you have the PERFECT composition.  You are happy with the result.  The printer you are using use 300 dpi.  You can print high quality print of 20" x 13.33" (resolution divided by 300).  NOW you use your FX.  It shoots wider than the DX.  You take the shot on the same spot.  You decided to crop your 6000x4000 jpeg to have the same look as your DX photo.  That means you crop the sides and you end up having 4000x2667 resolution JPEG.  That means wiht the same printer you can only have high quality print up to 13.33"x8.9".
> 
> The conclusion is.......  if you print 13.33"x8.9" OR SMALLER... without a doubt the FX print will look better while DX is slightly worse (more noise) but not that much worse if we shoot it at low ISO.  If you print something bigger than that, the DX will continue to print decent up to 20"x13.33" while the FX will need to use software interpolation to be able to print at 300 dpi that big.  You will start seeing pixelation if you dont interpolate it with a software.  If you interpolate, it is just guessing/adding pixels so your photo wont look as good.
> 
> Do you get it or not get it now?



THANK YOU!!  FINALLY!!!!


This is what I've been looking for the whole time!  Why didn't you say this to begin with?  Everyone kept explaining the difference between ff and crop over and over!  I was going as crazy as you must have been, lol!


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## Robin Usagani (Feb 29, 2012)

Thank god.. i can sleep well now LOL.


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## Carny (Feb 29, 2012)

Schwettylens said:


> Thank god.. i can sleep well now LOL.



We both will!

But not together.  No matter what kind of dress you're wearing!


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## WayneF (Apr 23, 2014)

kundalini said:


> *....................................DX 50mm.....................................................................FX 50mm...........................*





You did not compare them equally.    For all things equal, these should be compared as they actually were.  The DX image is cropped, specifically it should be shown only 2/3 the size of the FX (which then also makes the same subject be same size), because, *the same lens would of course project exactly the same size subject.   *   You did not show  that same image projected by the same lens.   The DX frame is already seriously cropped (to 2/3 dimensions), and should be shown that way, *because the same lens at same distance obviously projects exactly the same image view*, no matter which camera.

That is real world.   However, you introduced additional magnification changes in one of them.





> Here's what you paid admission for..............
> 
> 
> *....................................DX 35mm.....................................................................FX 50mm...........................*


 

Right that shows it, but  you don't mention what it shows (some won't otherwise get it.    )
   Here you are showing that *for any two images showing the same subject at same size* (at same aperture, but regardless of focal length or focused distance that is necessary to produce same subject size), then the depth of field is obviously the same.   This is very old stuff that has been known for decades.

Format size (film size, like even large 8x10 inch film, or whatever) appears to vary depth of field only because they necessarily use a much longer lens to magnify image to cover the larger film size.


Normal lens focal length for:

Compact camera -varies, around 7 mm
DX  - around 30mm.
FX - around 50mm.
8x10 inch film - around 300mm

This lens choice does of course affect depth of field.   300 mm has much less DOF than 7 mm (on any camera body).       Sensor size of course typically requires the specific lens.   Smaller images do require more enlargement (another factor).    But the cropped sensor size itself does nothing - it simply reproduces the image the lens projects on it.

Newbies ought to read up, at Depth of field - Wikipedia, the free encyclopedia

It may be a bit obscure, but it speaks of* magnification affecting DOF*.  Specifically,

"DOF is determined by subject magnification at the film / sensor plane and the selected lens aperture or _f_-number. For a given _f_-number,  increasing the magnification, either by moving closer to the subject or  using a lens of greater focal length, decreases the DOF; decreasing  magnification increases DOF. For a given subject magnification,  increasing the _f_-number (decreasing the aperture diameter) increases the DOF; decreasing _f_-number decreases DOF."

Note it points out that Magnification can be obtained by moving close to subject, or using a longer lens.  These are the factors that affect DOF (and aperture).


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## astroNikon (Apr 23, 2014)

> This is very old stuff that has been known for decades.



It might have been known for decades
but people ask about it because they haven't known it for decades
it's a learning process for many, some people start without knowing much but only how to push the shutter button.

I found it very helpful myself when I read it last year.


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## SCraig (Apr 23, 2014)

Four-year-old thread.  Times have changed.


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## astroNikon (Apr 23, 2014)

SCraig said:


> Four-year-old thread.  Times have changed.


Yeah, my FF switches between Full Frame and Crop by the push of a button and click of a dial.
I can see this real time in seconds ... back and forth.  How cool is that


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## WayneF (Apr 23, 2014)

SCraig said:


> Four-year-old thread.  Times have changed.



Oops!  I missed that, but you're right, sorry.  Something woke me up today, but somehow I managed to get into the wrong thread.


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## runnah (Apr 23, 2014)

FF vs DX is like Quantum physics

If you think you understand quantum physics, you don't understand quantum physics.


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## vintagesnaps (Apr 23, 2014)

Does having watched Quantum Leap count? 

I see the difference when I take along a film camera and my digital that isn't FF and shoot the same scene from the same vantage point - I get more stuff in the frame with the film camera. (So I just have to adjust accordingly, plan on a larger field of view with one and smaller with the other.) 

It's not rocket science (only quantum physics LOL).


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## KmH (Apr 23, 2014)

Only if you know what the real Quantum Leap actually is?


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## kundalini (Apr 23, 2014)

WayneF said:


> You did not compare them equally.    For all things equal, these should be compared as they actually were.  The DX image is cropped, specifically it should be shown only 2/3 the size of the FX (which then also makes the same subject be same size), because, *the same lens would of course project exactly the same size subject.   *   You did not show  that same image projected by the same lens.   The DX frame is already seriously cropped (to 2/3 dimensions), and should be shown that way, *because the same lens at same distance obviously projects exactly the same image view*, no matter which camera.
> 
> That is real world.   However, you introduced additional magnification changes in one of them.


*Prove it!*




> Right that shows it, but  you don't mention what it shows (some won't otherwise get it.    )
> Here you are showing that *for any two images showing the same subject at same size* (at same aperture, but regardless of focal length or focused distance that is necessary to produce same subject size), then the depth of field is obviously the same.   This is very old stuff that has been known for decades.
> 
> Format size (film size, like even large 8x10 inch film, or whatever) appears to vary depth of field only because they necessarily use a much longer lens to magnify image to cover the larger film size.
> ...


At the time of this post, there was much chatter about DX vs FX and nobody had the balls to demonstrate.  The consensus of questions was centered around the most common focal length..... 35mm vs 50mm of each format.  If you had read the original post of that thread, there were a couple of coded references that should have been paid attention to.  Specifically, _*"This is a v-e-r-y non-scientific lab results test. " *_and _*"(T)*__*his made sense and I did a reshoot..... on a Sunday afternoon, I had nowhere to go, and no chance of driving.......... getting the picture? " *_.  If you can't understand the inferences, then shame on you.  The afternoon started like this.....







By the time the post processing was done, there is no doubt I was completely soused.  But I will bet a dollar to a doughnut there was very little difference in any re-sizing, because I have a process.

Now I am the first to admit that aberrations are extremely possible, but on that particular day, a decent effort was put forward.


So here's my challenge to you WayneF, do your own bloody study of the DX versus FX with the most common lens choices and post your results to enlighten the masses (or the unwashed multitude, if that is your preference) to prove me wrong.  Otherwise, STFU.  




> _This is very old stuff that has been known for decades_


Really?  Then why is the question still being asked four years on?  You can bow your chest out all you like, but until you attempt to fail with examples, your words have very little significance.  I look forward to your results.


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## Braineack (Apr 24, 2014)

WayneF said:


> You did not compare them equally.    For all things equal, these should be compared as they actually were. ...That is real world.   However, you introduced additional magnification changes in one of them.



Are you looking at the same two pictures as the rest of us?



This is the DX image resized by 1.5x and placed directly over the FX shot.  Why would you expect the DX shot taken at the same position as the FX to be the same size?  The image size of the FX is 1.5x larger than the DX, so the image size must be scaled to show the effect.



> This lens choice does of course affect depth of field.   300 mm has much less DOF than 7 mm (on any camera body).       Sensor size of course typically requires the specific lens.   Smaller images do require more enlargement (another factor).    But the cropped sensor size itself does nothing - it simply reproduces the image the lens projects on it.



If he shot the monkey from 5 feet away at f/.6 with a 50mm lens, he'd have DOF of .67ft.
If he shot the monkey from 20 feet away (4x further) at f/5.6 with a 200mm lens (4x longer), he'd have a DOF of .67ft.



> Note it points out that Magnification can be obtained by moving close to subject, or using a longer lens.  These are the factors that affect DOF (and aperture).



yes, and this is why people will always say the FX will achieve better DOF--you can stand closer with a longer lens (narrower DOF), and compared to a crop you will get better background magnification coupled with narrower DOF for better bokeh.

It's pretty clear the see the background on the 50mm FX shot has much better bokeh compared to the 35mm DX shot.


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## astroNikon (Apr 24, 2014)

The LENS nor the IMAGE PROJECTION itself does not change on a FF lens (DX specific lenses, which are smaller glass project a smaller image).  It's the size of the camera sensor whether it takes a smaller portion of the image, or larger, as demonstrated above .. from what I understand. Thus the small sensor "crops" the FF image.



Braineack said:


> If he *shocked the monkey* from 5 feet away at f/.6 with a 50mm lens, he'd have DOF of .67ft.
> If he *shocked the monkey* from 20 feet away (4x further) at f/5.6 with a 200mm lens (4x longer), he'd have a DOF of .67ft.



I think this thread needs to be locked before it really derails




oops, too late


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## runnah (Apr 24, 2014)

KmH said:


> Only if you know what the real Quantum Leap actually is?




I just hope the next leap is the leap home.


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## astroNikon (Apr 24, 2014)

Here's another perspective/view to see

This is through a Viewfinder of a d600, which allows one to change between "crop" mode and FullFrame mode.

To the left is the CROP version. 
Notice the rectangular square box (drops the entire grid in FX mode). Anything outside of that box will not be in the photo, where as in FF mode then entire image is captured.

Versus on the right the normal look through the viewfinder as FullFrame - I use the grid turned on.

View attachment 71725View attachment 71726


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## WayneF (Apr 24, 2014)

kundalini said:


> WayneF said:
> 
> 
> > You did not compare them equally.    For all things equal, these should be compared as they actually were.  The DX image is cropped, specifically it should be shown only 2/3 the size of the FX (which then also makes the same subject be same size), because, *the same lens would of course project exactly the same size subject.   *   You did not show  that same image projected by the same lens.   The DX frame is already seriously cropped (to 2/3 dimensions), and should be shown that way, *because the same lens at same distance obviously projects exactly the same image view*, no matter which camera.
> ...



?   It is common knowledge (check manuals) that the D300 DX sensor is 23.6 × 15.8 mm  (page 409).  The D700 FX sensor is 36.0 × 23.9 mm (page 428), which is 1.5x larger than DX. 
 I suspect you already knew that.  It is pretty much the whole difference of DX vs FX, the entire point.

There are two significances...   One is that a smaller DX  image requires 1.5x more magnification to appear same size as FX (and DOF is entirely about subject magnification).  

Two is that (if using same lens standing at same place), that DX only captures a smaller central portion of the SAME image projected by the SAME lens...  DX obviously sees the exact same image, just cropped smaller around the edges.    We know this stuff.  We have to fit any conclusions in around the obvious facts.

We can of course use different lenses and stand at different places and see different views, but these are magnification changes again.



> By the time the post processing was done, there is no doubt I was completely soused.  But I will bet a dollar to a doughnut there was very little difference in any re-sizing, because I have a process.



Yes, that was the problem, it was my point.     You increased the magnification of the DX, out of proportion to the FX.  You resized unequal items to be same size, but they are not.




> So here's my challenge to you WayneF, do your own bloody study of the DX versus FX with the most common lens choices and post your results to enlighten the masses (or the unwashed multitude, if that is your preference) to prove me wrong.  Otherwise, STFU.



I didn't say you were wrong. You did what you did, and got what you got.    I said you unfairly compared unequal items, and then failed to make the real point.

But OK, see FX - DX Lens Crop Factor .     Which is my version. It is not about DOF, it is about what DX/FX means, and how they differ, and some advantages/disadvantages, including DOF.


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## Braineack (Apr 24, 2014)

WayneF said:


> You increased the magnification of the DX, out of proportion to the FX.  You resized unequal items to be same size, but they are not.



no he didn't.  He posted the image exactly as it would straight out of the camera, both resized for 400x600px.

why would he have posted a 233x400px image compared to a 400x600px image?  Why would someone resize differently based solely on the sensor size?

The whole reason there's a 35mm equivalent rating to lenses, is because the shot taken on a DX at 50mm, appears just like a shot taken at 75mm on an FX.



> I didn't say you were wrong. You did what you did, and got what you got. I said you unfairly compared unequal items, and then failed to make the real point.



are you suggesting the monkey's aren't the same?  Do you watch Mythbusters by any chance and also hater scientific method? what was unfair, did the FX camera get paid for the shoot but the DX worked for free?

His point wasn't to show the difference in DOF, or the advantages/disadvantages.  His point was to visually demonstrate the differences in sensor size and how the crop works.  Something many people still can't wrap their heads around because these simple discussions on a simple theory always turn into long drawn matches in semantics, misunderstanding, and pure self-loathing.  His post accomplished exactly the intent, in a visual, easy-to-understand way.

If you'd like to illustrate the differences in DOF/background between the two at various focal lengths with the camera in different positions to achieve the same framing, by all means do it.


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## WayneF (Apr 24, 2014)

Braineack said:


> WayneF said:
> 
> 
> > You increased the magnification of the DX, out of proportion to the FX.  You resized unequal items to be same size, but they are not.
> ...



Kundalini's work and post were good, and I suspect it only suffered from oversight, what he could have said.

Basics: Camera images are formed by two major components... the image projected by the lens at X resolution, and the capture of it by the sensor or film at Y resolution.  Then  we can manipulate it by how we prepare and show them.

You are saying pixels are pixels, we have what we have.    But there is a lot more, and I am speaking of the "image", and its "area" and thus its resolution.   The dimension that those pixels capture reflects the resolution projected by the lens, which definitely also affects the image - it is the image, the lens makes the image (the sensor merely tries to reproduce it).     To make the point be obvious, if we enlarge (magnify is the operative word) a small area of it, like say 100x100 pixels, and show it large on the monitor screen size, it really does not compare well (looks crummy).    Not the same thing at all.   OK, 100 vs 400 vs 600 is merely speaking about degree, but it is the same point.  Equal is equal, and not is not.   I am speaking of reproducing and comparing the same captured image from the lens.   You are speaking of the size of the container you keep it in.

Taken with the same lens at the same distance, DX is of course cropped smaller than FX.  Smaller is the word we should keep in mind.  It is the only difference, and again, magnification becomes the thought. 
But otherwise, the FX and DX images are of course exactly the same image (it was after all the same lens, the same projected image).  We are merely trying to reproduce that image.
And yes, FX 600x400 and DX 400x267 pixels would show the SAME AREA from the SAME LENS (a fair comparison).   
If shown representing actual original size, we see that DX is smaller, but we also see that image from same lens is the same (and it has original resolution).
If we enlarge the smaller one to instead be bigger too, we have arbitrarily changed things (namely, magnification and resolution), now unequal, not the same thing.



> His point wasn't to show the difference in DOF.



That is a valid point, he never said he was.  As mentioned before, I got into this old thread due to my error, which is still not clear to me how.     I think it was linked elsewhere.  Sorry about that, but his images are quite good to serve a very good point (which ought to be stated).


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## Braineack (Apr 24, 2014)

I hereby decree, by order of the King, that all images posted by DX cameras on TPF be sized 1.5x smaller than images from FX cameras.

Likewise, all thee subjects who wish to print their photos and hang on their walls, must print images from DX cameras 1.5x smaller than they would from FX cameras.


you're arguing such a stupid and dumb point.  for what?


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## WayneF (Apr 24, 2014)

Braineack said:


> I hereby decree, by order of the King, that all images posted by DX cameras on TPF be sized 1.5x smaller than images from FX cameras.




No, only if the entire point was to specifically compare them both to each other (to show their specific differences)...  fairly.   It is not a difficult concept.


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## Braineack (Apr 24, 2014)

That's just silly, and you know it, but you don't want to concede because this is the internet.

You're suggesting his test was bad/flawed/invalid, because he resized both images to the same dimensions; a constant. But you're treating that as if it's a variable that made a difference in the comparison, which is stupid.  Because if you're going to compare two photos, you're going to compare them at the same image size.

I'm certain, had he posted one photo at 267px and the other at 400px, you'd be bitching that they weren't the same size...


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## WayneF (Apr 24, 2014)

Braineack said:


> That's just silly, and you know it, but you don't want to concede because this is the internet.
> 
> You're suggesting his test was bad/flawed/invalid, because he resized both images to the same dimensions; a constant. But you're treating that as if it's a variable that made a difference in the comparison, which is stupid.  Because if you're going to compare two photos, you're going to compare them at the same image size.
> 
> I'm certain, had he posted one photo at 267px and the other at 400px, you'd be bitching that they weren't the same size...




I never said bad/flawed/invalid.  Sure, comparing final user results is valid enough, but comparing resolution needs to compare same things.     I pointed out that the two pictures did not compare the same lens at the same size, which is correct (and is a fundamental principle).  And I said that the second did not say the conclusion, which it didn't, but yes,  I was thinking DOF, the thread had in fact turned that way, and the OP had even later mentioned DOF.

No, I would not have bitched about a fair comparison that actually shows real.   I was asked above for my "own bloody study", to which I provided the link to FX - DX Lens Crop Factor
It shows it both ways, enlarged to same size (commonly done) and also still original size (to show the concept and comparison of original - what subject is actually about).   It was trying to make point of what DX/FX is.  But it is easy to see that DX enlarged to FX size can suffer (1.5x more magnification reduces resolution).  And the magnification reduces DOF, but the necessary equivalent-view using shorter DX lens or longer distance compensates DOF - but not for loss of resolution from magnifying smaller image to be larger (pixel density only tries to reproduce lens resolution, it can never add scene resolution - so lots of ifs and buts to debate).  

   However, still true that bigger normally does win perceptually - we see big things better, even if less clearly.  We like big things. Big wins, about every time.  It is a reason FX is big, to allow it (wide lenses are the other reason).    But comparisons ought to be fair, and should actually compare, all other things equal.

You may be aware that in the old days, we had several film sizes.  35mm film was extremely popular, but larger film was preferred commercially.  120 medium roll film was the same film emulsions, but it was used because their prints needed less magnification, and results were clearly better - they would sell.  Sheet film carried this to extremes, for same reason - same film emulsions, but in spite of the hardships of smaller apertures and much less DOF from much longer lenses.  An 8x10 inch film sheet can produce an 8x10 inch contact print.  Ever seen a contact print?      Compared to 35mm?   That is about magnification of the image (on the same film and print emulsion).   Magnification is an extreme concept in photography.  But when we always use the same gear, we lose sight of it. Some don't even know, cannot even imagine.  But DX cropping the lens view smaller is the same thing as smaller film cropping the lens view smaller.

Sorry that you are unable to get it.


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## Derrel (Apr 24, 2014)

I AM EAGERLY WAITING for this post to appear on pay-per-view, or failing that, to be available for internet download at least, in an unauthorized, Asian-market camcorder black-market copy, filmed in Hong Kong on some guy's shaky, hand-held camcorder...


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## astroNikon (Apr 24, 2014)

lol .. insert photo of someone kicking a dead horse ....


For newbies the OPs description answered the DX/FX question, which is what the target audience it was intended for.
I liked it and it helped me.  :thumbup:


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## astroNikon (Apr 24, 2014)

Derrel said:


> I AM EAGERLY WAITING for this post to appear on pay-per-view, or failing that, to be available for internet download at least, in an unauthorized, Asian-market camcorder black-market copy, filmed in Hong Kong on some guy's shaky, hand-held camcorder...


It's already available on DigitalRev youtube videos .. with a reenactment with characters

okay, it's not .... it sounded good though.


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## runnah (Apr 24, 2014)

blah this thread makes my dick itch...


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## Braineack (Apr 24, 2014)

runnah said:


> blah this thread makes my dick itch...


what doesn't?


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## runnah (Apr 24, 2014)

Braineack said:


> runnah said:
> 
> 
> > blah this thread makes my dick itch...
> ...



a cooling balm or salve.


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## WayneF (Apr 24, 2014)

Derrel said:


> I AM EAGERLY WAITING for this post to appear on pay-per-view, or failing that, to be available for internet download at least, in an unauthorized, Asian-market camcorder black-market copy, filmed in Hong Kong on some guy's shaky, hand-held camcorder...



LOL   If you have objections, it would seem more useful to specify what, why, how. Do you know any details, or do you just need to be cute?

You don't think that it is overwhelmingly significant to realize (as the previous test showed, but did not comment) that the same subject magnified to the same size at the same fstop... will produce exactly the same DOF, regardless of the lens focal length or focal distance used?   Technically a little less true of close distances, but seems like that ought help many confusions.   I want to say that has been known 100 years, but someone would probably say, no, it was 150 years.  

Without doubt, yes, it is ALL ABOUT THE CROP FACTOR.  That and film size is the only way the cameras differ.  Yes, sure, the smaller crop sensor does typically need to use a shorter lens, but regarding DOF too, the smaller DX sensor cropping the lens image smaller is exactly the same concept as the 35mm film size cropping a 120 negative size smaller.    Ratio is even similar,  60mm : 36mm = 1.67:1


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## Derrel (Apr 24, 2014)

WayneF said:


> Derrel said:
> 
> 
> > I AM EAGERLY WAITING for this post to appear on pay-per-view, or failing that, to be available for internet download at least, in an unauthorized, Asian-market camcorder black-market copy, filmed in Hong Kong on some guy's shaky, hand-held camcorder...
> ...




No, I have no objections to a resurrected, four year-old thread filled with back and forth and back and forth and lots of posturing and stuff...as I said, I'm eager to be able to get this thread as a download. As astroNikon mentioned, it's possible that the thread will be done as a re-enactment with characters playing the parts of the various participants. Keep in mind, when some guy plays necromancer, and brings a LONG DEAD THREAD back to life, it's a good idea if that guy actually reads, and understands the OP's premise before going into an entire re-hash of the original post, based on some premise that entirely misses the point of said, dead,buried, four year-old thread. And YES, when the thread was posted, back in 2010, I knew EXACTLY WHAT THE OP MEANT about a weekend day, "*and no hope of driving.*" So yeah, I actually did know the "details". I made a comment about that--dated 2010.

Hopefully, maybe the thread could be re-worked by a new producer/director/screenwriter crew, and maybe a brand new sequel released in theaters (and on Netflix!!!!!). Maybe a PG-13 type version, with Scarlett Johansson being the model, instead of Kundalini's kinda' ugly pink monkey... WHat an idea: a whole NEW POST, by a new director/producer/screenwriter!!!!!!!!!

I'd pay $7.50 to see that in the theater, I think.


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## Braineack (Apr 24, 2014)

$7.50 wont get you in a matinee here...


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## WayneF (Apr 24, 2014)

Derrel said:


> No, I have no objections to a resurrected, four year-old thread filled with back and forth and back and forth and lots of posturing and stuff....



Yes, being in *this* thread certainly was my mistake. Went wrong somewhere,  I still can't figure out how I got here.     Prowling around without enough attention obviously, got sidetracked.  Sorry about that part.

  I intended to be in this thread:  http://www.thephotoforum.com/forum/...th-field-lenses-relationship.html#post3215301

where yesterday you had posted there about DOF and my "it's all crop" nonsense, and then thought better I guess, at least apparently deleted it quickly, or someone did.  But I don't mind discussing it with you.

There you pointed out the obvious DOF difference in 35mm and roll film and sheet film, and digital compact, DX and FX, regarding depth of field.  Those factors are "all crop", so we already agree.

You seem to credit DOF to the film itself, but I realize you cannot mean it that way.  I feel sure you know and care.   
But sure, I will word it that way if you wish, yes, of course it is all crop. * Crop is the only difference in any of those cameras*, how much their sensor crops the lens view.   It could be worded how well the lens covers the film size, but of course, that is specifically about the crop size.
They of course do also necessarily use different lenses, but which needed magnification is ONLY because of the crop size, so it will see a normal view, so yes, of course it is all about crop.   And of course, their varying sizes also have to be enlarged differently later (more magnification), so again, it is all crop. 
   Other than aperture fstop, what does affect DOF is magnification, which could be lens focal length or focus distance, but all specifics come about because of crop size.   How hard is that?

You had said:   "If you WANT TO MAKE pictures that have VERY LIMITED depth of field, what people have done for well over 100 years, is to use a BIG piece of film."

That 8x10 is of course just a bigger crop size, pure and simple.    Of course, the film does not actually do anything about DOF, but the crop size demands use of the lens that does cause it.

So, how is this statement wrong?     If you want a drastic difference in DOF (for an assumed similar view of a subject), find a camera with a drastically different crop size.  (I just quoted your agreement)

If crop size is not the FIRST STEP, then what would be the first step?


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## vintagesnaps (Apr 24, 2014)

I haven't the foggiest notion what a quantum leap actually is, all I know is at the end of every episode what's his name leapt into another character in a different place - whew, the show would be on again another week! 

The thread by now just seems to be making this harder than it has to be.


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## TreeofLifeStairs (Apr 24, 2014)

I remember that show. Did he ever make it back to his correct time?


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## KmH (Apr 24, 2014)

runnah said:


> KmH said:
> 
> 
> > Only if you know what the real Quantum Leap actually is?
> ...


Niels Bohr explained how electrons are arranged around an atoms nucleus in discrete energy levels that are akin to discrete electron orbits.

Electrons are able to move from energy level to energy level, and when they change level they emit or absorb photons (light).
The energy level changes follow a Poisson statistical distribution which is part of how they were able to verify what Bohr had theorized.

But here is the non-intuitive quantum mechanical thing - When an electron jumps from one energy level to another it does not cross the space between the orbits - it just instantly appears at the new level and was called a Quantum Leap.


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## kundalini (Apr 24, 2014)

Mr. Fulton,
I do not doubt that you are well versed in your knowledge of photography.  I will not debate that and assume it to be true.  However, I do believe your recent immergence in this thread has left a sour taste in many mouths for the intentions of the original post.  With over 11K views and no significant disputes of my attempt to enlighten of what I originally presented, you now wish to be the cock of the walk with 6 months of membership under your belt.  Go ahead and bask in the sun of your formidable knowledge.  But you don't know me and I doubt you have vested the interest to find out my history on TPF.  It doesn't matter, but it is worth mentioning.

There is a difference between the letter of and the spirit of which you are attempting to interject from the effort I made years ago.  While the link you provided is valid FX - DX Lens Crop Factor, even though many examples of that same visual can be searched via Google and has been addressed several times on TPF, it only demonstrates an overview of the differences between FX versus DX.  The spirit in which I posted this thread was to reveal what interested people may actually see when they upload their image to their computer.  You know, from their memory card of an image they actually took and wondered what the difference would be between the formats.  Yeah, it was a kinda ugly monkey for a subject, but let me tell you that monkey has been a tireless friend for my experiments with photography.  I determined quickly not to bother living human beings with my experiments, or rather, while I was figuring things out.  Thats a good way to lose a friend or partners patience. 

So even though you state ___You did what you did, and got what you got. I said you unfairly compared unequal items, and then failed to make the real point._ , you are mistaken.  I made the exact point I was after.  While I may not be the expert of your caliber, I made a decent effort nonetheless, IMO.  You expressed that you are knowledgeable of my processes, but I have an opinion that you are SWAGing because you dont have a clue of what I did on that day.  Again, I challenge you, but dont try to give the same link as before.  Do a real world study (with or without a pink monkey) of what someone would see on their uploaded image and wondered what the difference would be.

If you continue with your l-o-n-g-w-i-n-d-e-d validations, Im afraid this thread may be locked.  That would be a shame.  At the expense of ego, are you willing to thwart efforts towards awareness of the uninitiated?  It is okay to take a step back.

Peace out.


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## WayneF (Apr 25, 2014)

kundalini said:


> Mr. Fulton,



Uh oh...

I can see now that you were offended, which certainly was not my intent, and  for that, I am sorry if it bothered you.    I did not imagine it was personal, and instead thought we discussed photography subjects here. But yes, I was indeed in the wrong place and did not even realize the thread was so old.  It was linked in another thread recently, and I was thinking DOF,  which unfortunately was on a different track than your purpose.   

Still, I thought I only  said two things.  One was I did say I thought you should have shown the  "same lens / different sensor" comparisons proportionate to actual original  size, and left additional enlargement out of it.  You disagreed, and  seem pleased with your choice, and of course, it was your choice.    Which clearly wasn't my own DOF notion, and which seemed to fail to impress you.  

    I did think there was much more potential though, and scaling original size still seems a reasonable idea, since you did do  exactly that in your second image posting (in reverse, enlarging FX 50% more  instead of DX less, but with same effect, both had same 50% enlargement degree  then).  I should have offered an attaboy, since your second image post also clearly shows the same lens view is obviously projected the same onto both  sensors, so obviously same subject size and DOF is expected. Same lens at same distance on two bodies must be exactly the same, because it is in fact the same lens and same projected image.  That is a major point of confusion about the DX/FX subject. We just have to show it equally. Which you did show well (both enlarged 50% more to be an equal comparison).    I'm not sure everyone grasped what they were seeing however, which seems a shame, there is so much there. 

In the last two compares in first post, and also your second image post which I did not comment on, you did  really well showing the same subject at same size, which must have been your intent, which showed same  DOF extending behind subject, regardless of different lens/distances  (used to show same size).  The distances are very close, really too  close to expect it perfect, but it still came out very well anyway.  It would be  easier at a few feet instead of a several inches.  Three ways you showed  this well though, with focal length and then distance in the first post, and  with same enlargement in the second.    Same image magnification any of the three ways is the same DOF (maybe not quite if too close).

Then two,   I did say you didn't comment on this in the first,  which you didn't.  I guess my saying that must be a bigger sin than I realize, apparently  you don't find it very helpful.       But three ways done so well does seem a pretty big deal nevertheless, IMO well worthy of  comment.     It would have been awesome if more comment were offered there, which it deserved, and I thought it was nice work which offered much more than you are willing to claim. Impressed me though, even if the omission. 

But clearly the fault was mine, maybe my comments could have added enough more to make it more clear what I noticed you  did there, and maybe less about what you didn't do since that bothered you. That part was not intended.  Additional comment now is probably not helping either.   I do regret that my notions were not useful to you, and do regret if you were offended.


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