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

[weepete]

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!

 

[beagle100]

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.

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

 

[Derrel]

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.

 

[Overread]

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.

 

[Designer]

However its a very hit and miss thing.

I see what you did there.

 

[vin88]

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.

bad engine example, try again. vin

 

[donscot]