# Is there any downside of using fullframe lens on a crop sensor body?



## donscot (Oct 21, 2019)

Hi all,
I know this subject is a bit contraversial, but I have the following scenario:
I have Sony A5100 and I bought Sony 1.8/50 mm FE lens which is designed for fullframe body. I've realised this after buying the lens... So far I have no problems using the FE on my A5100, but the main question is: Am I loosing quality in this case, or is there any downside of using the Fullftame lens on my crop A5100 body?

Judging by this (and other articles), there is no actual downside for my case, right?

What Happens if You Use a Full Frame Lens on Crop Sensor Cameras?

Should I go for the 1.8/50 mm crop lens?


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## Tropicalmemories (Oct 21, 2019)

I think the only issues are size and weight compared to a lens designed for crop sensors?

As you're not using the corners of the 'full frame' rectangle you may even get some improvements in edge sharpness.


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## donscot (Oct 21, 2019)

Well, then my next logical question will be: why would anybody sell a separate crop sensor, since the fullframe is working fine on both crop and fullframe? Maybe the factor is the price? Well, as far as I can see on the web, both 1.8/50 FE and 1.8/50 OSS are having similar price... So, I guess it is one of those marketing tricks of every company...


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## Overread (Oct 21, 2019)

f1.8 50mm lenses are basically the most bare bones simplistic designs of lens and are often priced low to encourage people to buy their first prime lens. 50mm lenses have been standard lenses for AGES so its a really well worn market slot which keeps the price low. 

Basically as said there's nothing wrong with using fullframe lenses on crop sensor bodies. In fact when it comes to more exotic and expensive high end lenses there's often only a fullframe option. Canon only makes a handful of crop sensor only lenses compared to the legion of fullframe ones, for example.

Weight and size are normally the benefits, a crop sensor lens of the same focal length and aperture will be smaller and lighter than a fullframe one (of the same age and quality). So for those who want a smaller, lighter lens the crop sensor 50mm will be their choice.


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## donscot (Oct 21, 2019)

Yeah, but I still don't get it... Why would any company manufacture a crop and full frame lens of the same type for two different bodies, since the only difference between the two is size? I assume every person will go for the fullframe lens in this case, and make a compromise with the weight difference (and we are taking about small difference in weight, right?) but will have a fullframe lens, which they can also use if decide to move on to the fullframe body some day...


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## 480sparky (Oct 21, 2019)

Size, weight and price.


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## Designer (Oct 21, 2019)

donscot said:


> Yeah, but I still don't get it... Why would any company manufacture a crop and full frame lens of the same type for two different bodies, since the only difference between the two is size? I assume every person will go for the fullframe lens in this case, and make a compromise with the weight difference (and we are taking about small difference in weight, right?) but will have a fullframe lens, which they can also use if decide to move on to the fullframe body some day...


Move away from the ubiquitous 50mm lenses, and you will find that the more "professional grade" lenses that are designed for "full frame" cameras will cost more.

Size, weight, and price.

Camera manufacturers will market an "entry level" camera body that is priced well below the professional grade cameras, and they will also design and manufacture "entry level" lenses to go with them.  

Furthermore, some lines of cameras and lenses are not fully compatible ("crop" to "full frame").  Always consult your user's manual for compatibility.


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## Soocom1 (Oct 21, 2019)

donscot said:


> Yeah, but I still don't get it... Why would any company manufacture a crop and full frame lens of the same type for two different bodies, since the only difference between the two is size? I assume every person will go for the full frame lens in this case, and make a compromise with the weight difference (and we are taking about small difference in weight, right?) but will have a full frame lens, which they can also use if decide to move on to the full frame body some day...


I am going to rehash a bit of history that many are not aware of. This isnt the full story, only one piece of it. 

In the late 1970's-80's solar panel manufacturing was making silicon wafers for solar panels. The standard size was 6" in diameter after manufacturing.

The computer chip (IC world) used the same process for the manufacture of computer chips. 
This eventually included the manufacture of silicon wafers for digital cameras. The standard size of an ingot (raw silicon form where the wafers come from) were finished also to 6". 

A 6" dia. wafer produces four 35mm full frame sensors. While the same wafer produces eight to ten APS sized sensors with much less waist. 

Economics.


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## donscot (Oct 21, 2019)

Yeah. After breaking this into pieces it make sence now. Thank you for clearing this for me guys. I am still learning...


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## photoflyer (Oct 21, 2019)

In the Canon DSLR world it is EF/S for crop and EF for both crop and full frame.  For me there is actually an  advantage to putting the EF glass on the crop as it increases the effective focal length by 1.6 so the 300mm F4 L becomes 480mm.  This is a disadvantage when shooting landscapes where a wide field of view is desired.


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## ronlane (Oct 21, 2019)

In your case, since you already own the body and the glass there isn't any negatives to it.

As it was mentioned using ff glass on a crop sensor can help with corner to corner sharpness because you aren't "using" all of the glass.

There is really is no reason for the companies to make a bunch of crop sensor glass. Mom or Dad with camera (MWC or DWC) will be just fine with the entry level glass to take photos of the kids. But once you've gotten past a certain stage or shoot with a quality piece of glass, then you realize that no matter the body you have GLASS MATTERS.

Sorry to yell that but it really does matter.


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## donscot (Oct 22, 2019)

Thanks for breaking this for me guys.


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## weepete (Oct 22, 2019)

I was under the impression that EF-S mount was created so that Canon could scale down exising lens designs and use cheaper and lighter materials as opposed to designing new lenses by scratch. 

The only real downside to using EF lenses is that the focal lengths of EF mount lenses are optimised for full frame cameras so can be a bit weird. One of my favorite focal lengths used to be 24-105mm but on a cropped sensor camera the wide end is more like a short telephoto where the EF-S 15-85mm is in my opinion much more flexible.


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## donscot (Oct 22, 2019)

Is the focal length of 1.8/50 mm of a ff lens changes to 75 mm on a crop body due to the 1.5 crop factor, or it stays 50 mm?


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## ronlane (Oct 22, 2019)

The lens is a 50mm on both full frame and crop sensor. But when mounted on the crop sensor the field of view is less than 50mm making it look like a 75mm on a Nikon (1.5) and 80mm on a Canon (1.6) full frame camera.


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## Designer (Oct 22, 2019)

donscot said:


> Is the focal length of 1.8/50 mm of a ff lens changes to 75 mm on a crop body due to the 1.5 crop factor, or it stays 50 mm?


Of course, nothing actually changes.  

The only thing that appears to be different is the field of view (FOV).  

Try this at home:  Look at a scene with one eye, then hold an empty paper roll core up to your eye, and you'll see much less of that same area.  

Note: This is only an exercise to represent a reduced FOV, and is not intended to represent any differences in sensor size or focal length.


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## Soocom1 (Oct 22, 2019)

There is a huge misconception over the FF v. crop that I got hammered on yet is being repeated here. 

APS sensors are just that. APS sensors. 

There really isn't any real magnification taking place.  The "magnification" is seen because of the smaller area that when the image is enlarged to a standard size like a 4x6 or 8x10, the smaller image capture has to be enlarged more. 

BUT, that also means that the pixels in the image are enlarged the same amount and thus a lower actual resolution if compared to a comparable FF image. 
A digital camera built with lenses specific to APS image areas are not "crop". 

The "Crop" aspect is when you use a FF lens on an APS camera because as stated, its simply a smaller area captured. The mounting distance on a "crop" camera is the same as a FF. Just a smaller image area.


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## Derrel (Oct 22, 2019)

Soocom1 said:


> There is a huge misconception over the FF v. crop that I got hammered on yet is being repeated here.
> 
> APS sensors are just that. APS sensors.
> 
> ...


When you say the mounting distance is the same, if you mean the flange on the lens to the focal plane, which is commonly called the flange focal distance, this distance is actually not the same in Canon brand lenses, but it's the same in other brands such as Nikon or Sony or Pentax. Because the distance is different the Canon ef-s lenses extend farther into the body and cannot be used on Canon full-frame cameras or even Canon aps-h cameras like the 1DS series. On Nikon cameras their smaller image Circle DX lenses can be mounted and used on full frame or FX models series cameras.


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## Soocom1 (Oct 22, 2019)

Derrel said:


> Soocom1 said:
> 
> 
> > There is a huge misconception over the FF v. crop that I got hammered on yet is being repeated here.
> ...


Ergo: Digital systems. Ergo; not actually a crop camera or more accurately cropped factor unless using an EF lens. 
The EOS line of DSLR's (M and R must be excluded here) uses the same mounting distance in the camera. 
The lenses are different betweent he EF and EF-S. But if the APS BODIES can mount the EF lenses, the mounting distance IS the same. 

When I spoke before over the image being exactly the same, this is what I was referring to. 

The mounting distance of the EOS system (APS or FF) is the same, thus the "crop" aspect is only when the EF lens is used. 
No you cannot mount an EF-S lens to the FF body, but the mounting distance of the EOS APS cameras are the same because if they were not, the focus on an EF lens mounted on an APS camera wouldn't hit infinity.


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## Derrel (Oct 22, 2019)

Ef-s short mount. ... the rearmost portion of the lens itself extends farther into the camera body, so far that the mirror in EF cameras will strike the back edge of the lenses. There was no technical reason to do this, as other camera manufacturers clearly saw. I think it was a way to make low priced ef-s lenses unusable on full frame and aps-h model cameras, as a way to force users who wished to move to different format bodies to buy all new lenses. Canon is a lens maker as well as a body maker.


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## Soocom1 (Oct 22, 2019)

Derrel said:


> Ef-s short mount. ... the rearmost portion of the lens itself extends farther into the camera body, so far that the mirror in EF cameras will strike the back edge of the lenses. There was no technical reason to do this, as other camera manufacturers clearly saw. I think it was a way to make low priced ef-s lenses unusable on full frame and aps-h model cameras, as a way to force users who wished to move to different format bodies to buy all new lenses. Canon is a lens maker as well as a body maker.



Actually having talked to an engineer who worked for Canon in the early 2000s it had to do with the fact that the EF-S lenses allowed for lower actual prime lenses rather than short end (back focus) telephoto designs. 

Canon thought that APS sensors would take over and eliminate the 35mm geneara. 
FF has in comparable pixel size a better image AND right out of Chevy's playbook with the Camaro, make the FF a high end commodity like  Z28 (V8) over the "regular" APS size (V6) stuff.


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## Derrel (Oct 22, 2019)

Soocom1 said:


> Derrel said:
> 
> 
> > Ef-s short mount. ... the rearmost portion of the lens itself extends farther into the camera body, so far that the mirror in EF cameras will strike the back edge of the lenses. There was no technical reason to do this, as other camera manufacturers clearly saw. I think it was a way to make low priced ef-s lenses unusable on full frame and aps-h model cameras, as a way to force users who wished to move to different format bodies to buy all new lenses. Canon is a lens maker as well as a body maker.
> ...


Well despite what your engineer friend told you Canon has not followed through much on that idea but they have released three aps-c EFS prime lenses each one priced at around $200. I actually do not believe what he said, since aps-c prime lenses have been built in very few cases, and have not sold well, and have not gained hardly any traction. Both Canon and Nikon have released just a few aps-c or DX prime lenses, and they have been very poor sellers. I can't think of the last person I heard discussing an aps-c prime lens, even though the three Canons look really neat to me.

The decision by Canon to make a lens line/ mount that is not usable on their better cameras was in my opinion quite foolish. Nikon, and Sony, and Pentax, decided to make their lenses fully interchangeable between their aps-c cameras and full frame models. Trying to force consumers into a cattle pen was not a good idea.

Nikon has a 10.5 mm, a 40 mm, and an 85 mm, and perhaps others. The Canon company has a really appealing,to me at least, 24 mm F 2.8 pancake, that is a pretty much a weird length when used on a 1.6 X sensor. I do like a pancake lenses however, and have owned two over the years.


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## Soocom1 (Oct 22, 2019)

Derrel said:


> Soocom1 said:
> 
> 
> > Derrel said:
> ...


Not arguing the foolishness of the decision. 
But remember this was late 2001 an early 2002. the decision at that time was also geared directly toward debunking the Kodak DCS pro. That was almost 20 years ago.  things change including the decision of Canon, Minolta and others on the APS FILM line to begin with. 
(Ergo the EOS Ixe.) I mounted my now deceased 35-350 on that camera and was shocked over how it actually performed. 

Dont forget the EOS 10D either. An APS SLR with EF mount only.   

Kodak, Motorola, Minolta, IBM, the list is long on stupid corporate decisions. 
simply because something didn't come to fruition doesn't mean it wasn't tried.


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## Soocom1 (Oct 22, 2019)

Also, Canon's derision to put plastic mounts ont he lenses. 
I just got an order from UPP for a 55-250 EF-S that has two broken mounting flanges. 
Now I need them for the wedding THIS FRIDAY, and dont have time to reorder the lens or return it. 

I am certain that many others who have had plastic mounts also can attest to the idiocy of that, but it still goes on. 

The 50mm F1.8 old version has plastic mounts, but the STM has steel. Why do you think that is?


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## Derrel (Oct 22, 2019)

..I have one plastic mount lens the old Nikon 28 to 80 D series, from the film days of the 1990s. So far it has held together for over 15 years for me, and I have made some decent pictures with it including one of my very favorite pictures of my young son. The 28-80mm D is a wobbly lens... the front extending part of the zoom barrel wobbles quite a bit, but I bought it and used it on my Nikon d2x around 2005. I think I paid $35 for it. This is a full-frame zoom lens used on a crop-frame Nikon, and this photo made around 2006 is perhaps one of my all-time favorite shots of my young son.


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## photoflyer (Oct 22, 2019)

weepete said:


> One of my favorite focal lengths used to be 24-105mm but on a cropped sensor camera the wide end is more like a short telephoto where the EF-S 15-85mm is in my opinion much more flexible.



You disagreed with my post but this appears to make my point.  I have both of these lenses.  I can't put the 18-55 EF/S on the full frame but I can put the 24-105 on both.  When I want to shoot landscapes on the crop I use the 18-55 even though the 24-105 is L glass and much better quality.  The 18-55 gives a wider view on the crop body.


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## weepete (Oct 23, 2019)

photoflyer said:


> You disagreed with my post but this appears to make my point.  I have both of these lenses.  I can't put the 18-55 EF/S on the full frame but I can put the 24-105 on both.  When I want to shoot landscapes on the crop I use the 18-55 even though the 24-105 is L glass and much better quality.  The 18-55 gives a wider view on the crop body.



Yes, I did. If you want an explaination here you go:



photoflyer said:


> In the Canon DSLR world it is EF/S for crop and EF for both crop and full frame.  For me there is actually an  advantage to putting the EF glass on the crop as it increases the effective focal length by 1.6 so the 300mm F4 L becomes 480mm.  This is a disadvantage when shooting landscapes where a wide field of view is desired.



It's got nothing to do with the lens mount, so an EF lens will give the same image as an EF-S lens of the same focal length when mounted on the same camera body. It's to do with sensor size and the portion on the image circle that's covered by the sensor. 

Also effective focal length is actually a thing in optics. By definition, the effective focal length is the distance between the rear principal point, and the rear focal point of the lens.

Plus the focal length does not change, so a 300mm lens is still a 300mm lens no matter if it's mounted on a crop, full frame, medium format, m4/3rds, or large format or whatever.


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## photoflyer (Oct 23, 2019)

weepete said:


> Plus the focal length does not change, so a 300mm lens is still a 300mm lens no matter if it's mounted on a crop, full frame, medium format, m4/3rds, or large format or whatever.



One hundred percent true.  But when I shoot sports I have the 300 F4 on the crop because it is equivalent to 480 mm relative to the same lens on the full frame. I use the 70-200 on the full frame.  This first gives me the maximum reach and the second is best for when the action is close.  

The semantics of this are interesting.  It reminds me of something in aviation.  Cessna put a 160 hp engine on the 172.   Then, later you could upgrade to 180 hp by simply changing the prop.    So was it really still 160 or was it 180?  The answer is that it is the combination of the two that results in one or the other.


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## petrochemist (Oct 23, 2019)

photoflyer said:


> In the Canon DSLR world it is EF/S for crop and EF for both crop and full frame.  For me there is actually an  advantage to putting the EF glass on the crop as it increases the effective focal length by 1.6 so the 300mm F4 L becomes 480mm.  This is a disadvantage when shooting landscapes where a wide field of view is desired.


The crop factor you're quoting is a function of the sensor & applies to any lenses, it doesn't change between EF & EF/S lenses.


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## petrochemist (Oct 23, 2019)

Derrel said:


> When you say the mounting distance is the same, if you mean the flange on the lens to the focal plane, which is commonly called the flange focal distance, this distance is actually not the same in Canon brand lenses, but it's the same in other brands such as Nikon or Sony or Pentax. Because the distance is different the Canon ef-s lenses extend farther into the body and cannot be used on Canon full-frame cameras or even Canon aps-h cameras like the 1DS series. On Nikon cameras their smaller image Circle DX lenses can be mounted and used on full frame or FX models series cameras.


The flange focal distance of EF & EF-S lenses IS the same (44mm) but the glass elements of the EF-S sometimes come further behind the flange than the do on EF. This causes the risk that the larger mirror on FF & APSH bodies will foul on the rear element.

The mirrorless mounts made by Canon have quite different flange focal distances (18mm for the EF-M & 20mm for newer the EF-R), as indeed do their old FD lenses (42mm), their cinematic mounts (29mm or 20mm on the VL range) & their original screw mount (28.8mm)...
I don't know of anyone else who has had quite as many complete redesigns of their lens mounts as Canon has!

Nikon, Sony & Pentax stick to a single flange distance for all the minor variants of their SLR mounts & then use another single value for their mirrorless mounts - in the case of Pentax the same SLR mount was used for their mirrorless body.


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## weepete (Oct 24, 2019)

photoflyer said:


> One hundred percent true.  But when I shoot sports I have the 300 F4 on the crop because it is equivalent to 480 mm relative to the same lens on the full frame. I use the 70-200 on the full frame.  This first gives me the maximum reach and the second is best for when the action is close.
> 
> The semantics of this are interesting.  It reminds me of something in aviation.  Cessna put a 160 hp engine on the 172.   Then, later you could upgrade to 180 hp by simply changing the prop.    So was it really still 160 or was it 180?  The answer is that it is the combination of the two that results in one or the other.



Use it for any reason you like mate! But to use your engine analogy don't try and tell me that changing the prop increases the size of your cylinders!


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## beagle100 (Nov 16, 2019)

petrochemist said:


> Derrel said:
> 
> 
> > When you say the mounting distance is the same, if you mean the flange on the lens to the focal plane, which is commonly called the flange focal distance, this distance is actually not the same in Canon brand lenses, but it's the same in other brands such as Nikon or Sony or Pentax. Because the distance is different the Canon ef-s lenses extend farther into the body and cannot be used on Canon full-frame cameras or even Canon aps-h cameras like the 1DS series. On Nikon cameras their smaller image Circle DX lenses can be mounted and used on full frame or FX models series cameras.
> ...



actually Canon EF-S  lens can be used on full frame camera bodies ... (with modification)
but it's much easier with mirrorless
*www.flickr.com/photos/mmirrorless*


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## Derrel (Nov 16, 2019)

I would love to hear about this EF-S on full-frame Canon body modification. You are the first person I've ever heard who has said that this is possible. I can't imagine how this is done since the ef-s lenses are allowed to protrude farther into the body, and the rear elements on various ef-s lenses are in grave danger of being struck by the mirror on full frame cameras.


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## Overread (Nov 17, 2019)

I've heard it done with a few of them and some of the 3rd party ones. However its a very hit and miss thing. Some don't protrude to far into the barrel and its all fine; some are very hairs breadth distance from damage and others will cause damage. Basically you have to research it because if you get it wrong your mirror will hit the back of the lens. The lens will likely be fine (but any marks on the rear element will appear in photos); whilst the mirror will likely break the mechanism which means an expensive mirror replacement.


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## Designer (Nov 17, 2019)

Overread said:


> However its a very hit and miss thing.


I see what you did there.


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## vin88 (Nov 17, 2019)

photoflyer said:


> weepete said:
> 
> 
> > Plus the focal length does not change, so a 300mm lens is still a 300mm lens no matter if it's mounted on a crop, full frame, medium format, m4/3rds, or large format or whatever.
> ...


      bad engine example,  try again.   vin


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## donscot (Nov 30, 2019)




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