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

[Designer]

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.

 

[Soocom1]

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.

 

[Derrel]

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.

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.

 

[Soocom1]

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.

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.

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.

 

[Derrel]

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.

 

[Soocom1]

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.

 

[Derrel]

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.

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.

 

[Soocom1]

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.

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.

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.

 

[Soocom1]

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?

 

[Derrel]

..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.

 

[photoflyer]

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.

 

[weepete]

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:

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.

 

[photoflyer]

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.

 

[petrochemist]

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.

 

[petrochemist]

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.