Canon Full Frame body with crop mode ( that can use EF-S lenses)

[Angryoak]

Is a Canon Full Frame body with crop mode (that can use EF-S lenses) outside of the realms of possibility? I mean Nikon can do it, and it would be ideal if one could still use quality glass that is accumulated  (eg:- EF-S 17-55 USM IS F2.8 ) when graduating to a FF, and also be able to utilise a crop reach on say 70-200 2.8 when desirable.

[akiskev]

I think it's not possible for a FF Canon reflex, because the mirror will be hitting the back of the ef-s lens..
Maybe with a FF mirrorless it will be possible!

[AvTvM]

it would only be a problem with the current EF-S 10-22 since that is the ONLY EF-S lens that takes some advantage of the EF-S short back flange concept (rear element closer to sensor). All other current EF-S lenses have no rear elements protruding into the mirrorbox.

[JR]

I could be wrong but I thought that only Nikon could do it because they hold the patent for it.  So for sure Canon can technologically do it, but if it anything remotely close to the way Nikon does it, they wont be able to because of Nikon's patent.  That was my understanding...maybe soomeone can confirm...

Jacques

[cfargo]

Why do you need to crop in the Camera?  Why not just do it in Post so that you have the option to do or not do later?  As far as EF-S Lenses, they don't make any L ones so why even consider them? This is just my thought process.

[bainsybike]

it would only be a problem with the current EF-S 10-22 since that is the ONLY EF-S lens that takes some advantage of the EF-S short back flange concept (rear element closer to sensor). All other current EF-S lenses have no rear elements protruding into the mirrorbox.

Are you sure about that?  I've just had a look at my EF-S lenses (15-85, 18-55, 55-250 as well as the 10-22) and they all seem to have the same protrusion.

[DzPhotography]

I think it's not possible for a FF Canon reflex, because the mirror will be hitting the back of the ef-s lens..
Maybe with a FF mirrorless it will be possible!

to my knowledge this is correct

[Ellen Schmidtee]

I could be wrong but I thought that only Nikon could do it because they hold the patent for it.  So for sure Canon can technologically do it, but if it anything remotely close to the way Nikon does it, they wont be able to because of Nikon's patent.  That was my understanding...maybe soomeone can confirm...

Jacques

Canon DSLRs already have mirror lockup. Canon pocket cameras can autofocus using contrast detection. The rest is technicalities, specifically -

1. A way to turn the camera off with the mirror locked up.

2. Check if an EF-S lens is connected to the camera, and if so -
2.1. If mirror is down, keep it down, display a message on the back screen, and under no condition move it up.
2.2. If mirror is up, keep it locked up, and use contrast detection to autofocus.

[AvTvM]

it would only be a problem with the current EF-S 10-22 since that is the ONLY EF-S lens that takes some advantage of the EF-S short back flange concept (rear element closer to sensor). All other current EF-S lenses have no rear elements protruding into the mirrorbox.

Are you sure about that?  I've just had a look at my EF-S lenses (15-85, 18-55, 55-250 as well as the 10-22) and they all seem to have the same protrusion.

Thanks!  You are right, I stand corrected.

Just checked it again myself. The physical protrusion is the same, only the rear lens element seems to not really fully use it - except at the 10-22 where it does come back all the way, and the 60 Macro seems to use a small part of the way.

[Radiating]

There's little to no practical reason to use an EF-S lens with a full frame body. Comprable full frame lenses will always get better resolution. In fact I made a list a while ago of every EF-S lens and the coresponding full frame lens at that price range and in every case the full frame lens was sharper than the EF-S lens in LPPM. Meaning using EF-S lenses would always be more expensive and result in lower quality. There would be some rare situations where it would be a good idea to be cross compatible though I'm sure though.

[smirkypants]

Why do you need to crop in the Camera?  Why not just do it in Post so that you have the option to do or not do later?  As far as EF-S Lenses, they don't make any L ones so why even consider them? This is just my thought process.

A couple of reasons. First, if you could see the cropped view properly in the viewfinder, you could frame the picture better and get a better shot.

Secondly, and more importantly, I would be shooting 16 ~ 18MP RAW files instead of 36 ~ 45 MP RAW files. This translates into much smaller files, much less wasted space, much higher equivalent capacity on the CF cards and much faster write speeds. All of these are important if you're shooting sports.

[awinphoto]

The mirror, ever since the 20D was the problem... If i'm not mistaken, the 20D was the first camera that allowed such as lens with a recessed back to fit inside with some tweaking of the mirror placement.  It's been a good 8-9 years ago so it's hard to remember vividly the details... the 10D, while being a crop camera, because the mirror is in the same spot as all the other FF cameras, cannot take ef-s lenses.  I have heard of work arounds such as removing the back element of the lenses, and some 3rd party lenses dont have an extended back which may or may not work with the sensor, albeit, the image circle is not big enough for FF so you get what you get from that lens.  I'm not sure how nikon does it, or if their lenses are designed similar to canon's in the rear of the ef-s lens, but unless canon implements a mirror to either slide back a bit or has a mirror lock up/live view only with ef-s, I dont know how they could work around it without redesigning lenses, which i dont see happening. 

[EYEONE]

If you really wanted to put an EF-S lens on a FF camera you could use extension tubes. It would vignette badly of course but it can be done.

[ejenner]

OK, Nikon can do it because their sensor to mount distance is larger than EF mount.  Hence their DX lenses don't hit the mirrors and can be mounted on the FF Nikons.

Of course this is exactly the reason you can use Nikon F mount lenses on Canon with a simple adapter with no internal glass, where as you cannot use an EF mount on a Nikon.

In fact the short Canon mount is very nice four mounting 3rd party lenses and was a great idea until the 'crop' format lens came along.   Actually apart from not being able to mount EF-S lenses on FF, the short mount distance is a very nice feature IMO, but may in part also explain why Canon has a harder time designing FF UWA lenses.

[Lyra Video Productions]

Why do you need to crop in the Camera?  Why not just do it in Post so that you have the option to do or not do later?  As far as EF-S Lenses, they don't make any L ones so why even consider them? This is just my thought process.

A couple of reasons. First, if you could see the cropped view properly in the viewfinder, you could frame the picture better and get a better shot.

Secondly, and more importantly, I would be shooting 16 ~ 18MP RAW files instead of 36 ~ 45 MP RAW files. This translates into much smaller files, much less wasted space, much higher equivalent capacity on the CF cards and much faster write speeds. All of these are important if you're shooting sports.

Another reason, and correct me if I'm wrong somebody, it could be useful for video for a few reasons. Beyond the ability to use cropped lenses, in video this would also allow you to "zoom" in (in theory) without a loss in resolution.  Since video is only 1920x1080 pixels and takes samples from the larger sensor, this cropping would just be taking the sampled pixels from different crop values, still giving you full HD 1920x1080.

I'm too lazy to check the D800 stats, but isn't this a video feature it has?

EDIT: Okay I'm not too lazy afterall.  It has it: http://imaging.nikon.com/lineup/dslr/d800/features02.htm