Canon EF lens (equivalent) compatibility

jgoetz4

Morning Folks,
I believe that the red dot on a Canon lens indicates that it is compatible with both ff & 1.6x crop cameras, whereas, a white dot indicates that it is an ef-s lens, compatible only with 1.6x crop cameras due to the mirror assembly. If that's the case, then wouldn't my Tamron 17-50 2.8 be compatible with a ff camera since it has a red dot, even though it has the Di designation ? Perhaps it is compatible, however, with severe vignetting ? Just curious since I am considering a 5D. Thank you :thumb
Have a good day
Jim...

cmason

jgoetz4 wrote:

Morning Folks,
I believe that the red dot on a Canon lens indicates that it is compatible with both ff & 1.6x crop cameras, whereas, a white dot indicates that it is an ef-s lens, compatible only with 1.6x crop cameras due to the mirror assembly. If that's the case, then wouldn't my Tamron 17-50 2.8 be compatible with a ff camera since it has a red dot, even though it has the Di designation ? Perhaps it is compatible, however, with severe vignetting ? Just curious since I am considering a 5D. Thank you
Have a good day
Jim...

Well, it depends. In Tamron's alphabet soup of product designations, the Di does not mean crop camera, but it means the lens have coatings and other bits to make use with Digital cameras better. So, technically a Di is not specifically intended for crop cameras, but in practice may vignette on full sensor cameras...you need to read reviews to see if it is meaningful to you. The Di-II lenses do have the EF mounting hardware, and the back lens elements do not protrude beyond the lens mount, so it will fit safely on an EF-S compatible camera. However, they will vignette like crazy on full frame bodies, since they don't have a large enough image circle.

jgoetz4

cmason wrote:

Well, it depends. In Tamron's alphabet soup of product designations, the Di does not mean crop camera, but it means the lens have coatings and other bits to make use with Digital cameras better. So, technically a Di is not specifically intended for crop cameras, but in practice may vignette on full sensor cameras...you need to read reviews to see if it is meaningful to you. The Di-II lenses do have the EF mounting hardware, and the back lens elements do not protrude beyond the lens mount, so it will fit safely on an EF-S compatible camera. However, they will vignette like crazy on full frame bodies, since they don't have a large enough image circle.

Good Morning & thank you
I'll do some research and see if I can find pictures taken with this lens on a ff camera.
Have a good day
Jim...

Robinivich

I've read somewhere that sigma doesn't build EF-S mounts, strictly standard EF, so you should be able to mount any of their DC lenses to, say, a 5D, it's just likely to give horrific vignetting, and probably nasty image quality at the extreme borders.

This is probably true with all 3rd parties, think of it, you've spent how much money reverse engineering a mount that's 99.99% compatible, and now, given the choice, do you want to do it all over again? Granted there'll be similarities between EF and EF-S but here's an example of how an EF-S lens behaves on a 1dsIII: http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx Scroll down to the bottom for a nice explanation.

It seems there's different camera/lens communication, in addition to physical differences.

Photoskipper

Robinivich wrote:

I've read somewhere that sigma doesn't build EF-S mounts, strictly standard EF, so you should be able to mount any of their DC lenses to, say, a 5D, it's just likely to give horrific vignetting, and probably nasty image quality at the extreme borders.

This is probably true with all 3rd parties, think of it, you've spent how much money reverse engineering a mount that's 99.99% compatible, and now, given the choice, do you want to do it all over again? Granted there'll be similarities between EF and EF-S but here's an example of how an EF-S lens behaves on a 1dsIII: http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx Scroll down to the bottom for a nice explanation.

It seems there's different camera/lens communication, in addition to physical differences.

It seems to be true that Sigma lens "fit" the EF mount but need to be careful.

I got the Sigma 18-200 lens from the old 300D. Luckily I did not mount to the 5D at all. I just tried it after reading this quote, I found the Sigma lens is very tight to mount on the 5D. It needs a lot of force to twist the lens. I gave up halfway to avoid any potential damage to either the lens or my 5D.

I doubt it is 100% compatible. You may wish to get your hands on to try it before decide whether it is really fit.

jgoetz4

Good Morning and thanks to all who responded Apparently it will work on a ff camera, however, it will vignette to about 21mm, before becoming useful. The vignetting effect may not be a bad idea after all. Possibly similiar to a Holga camera without the light leaks
Have a good day
Jim...

Scott_Quier

The red/white dots on 3rd party lens can only reliably be used to align the lens to the camera. Reading anything more into it is asking for trouble.

Read the descriptions carefully so you know what you're buying. Not all 3rd party lenses are intended for FF cameras. On the flip side, of course, any lens that mounts to a FF camera will also mount and function on a 1.6 crop camera (I think - watch, there'll be an exception and I'll be called out for it - one can only hope ).

ziggy53

Jim,

Understand that "severe vignetting" means "hard cutoff" at the limits of the image circle of coverage. This is further attenuated (on most lenses) by a rectangular mask at the backside of the lens.

The Tamron 17-50mm, f/2.8 SP XR Di II LD Aspherical [IF] is already vignetting at 1.4 on a crop 1.5x camera (Nikon), so you really cannot consider it any more than that. A crop 1.5x lens on a Canon 5D with a pixel density of 14,866 pixels per square mm will yield a usable image of 5,496,257 pixels, or about 5.5 MPix.

Note that a Nikon D3 with a DX lens will produce a 5.1 MPix image, and the D3 has a similar pixel density to the Canon 5D, so I think my figures are accurate.

ziggy53

jgoetz4 wrote:

Good Morning and thanks to all who responded Apparently it will work on a ff camera, however, it will vignette to about 21mm, before becoming useful. The vignetting effect may not be a bad idea after all. Possibly similiar to a Holga camera without the light leaks
Have a good day
Jim...

If the lens mounts and does not conflict the mirror (be very careful about this), you can expect that exposure may be affected and that auto exposure may be limited because of the strong black "frame" created from the extreme vignetting.

Tee Why

Only Canon makes an EF-S mount for lenses that have a smaller image circle made for APS-C sized sensors. Hence you cannot mount a EF-S Canon lens on anything other than a body that has a EF-S mount. So while the Canon 10D has a APS-C sensor, it has an EF mount and will not accept an EF-S lens.

All third party makers who make lenses for APS-C sensor (hence a smaller image circle) use EF mounts. Hence they will mount to any Canon slr that uses an EF mount. But since the image circle is smaller, placing such a lens will produce vignetting till you zoom back if you mount it on a full frame body or a 1D series which have a 1.3x crop factor.

Sigma denotes the smaller image circle with a DC, Tokina with a Dx, and Tamron with a Di II.

The little dot on the lens barrel is used to show where the EF mount needs to be aligned and is not color coded. Sigma uses white, Tokina uses white, and Tamron uses red IIRC.

Canon uses the red dot for the EF and a white pyramid for the EF-s and they are actually on differnt location of the lens barrel as well IIRC.

This is a big area of confusion but basically if you have a EF-S mount, it will work with both EF-S and EF lenses.

If you have a EF mount, it will only work with EF lenses.

IF you have a sensor larger than a APS-C and use a lens that is made for APS-C sized sensor, you will get vignetting irrespective of the mount of course.

rebelxtnewbie

Canon's EF-S uses a short back focus system (lens protrudes further back) which I believe is similar to how Four-Thirds lenses are.

Sigma and Tamron use an EF mount but with a smaller image circle. Thats why you can still mount them on EF mount cameras.

Robinivich

Some of the EF-S lenses will actually produce an image large enough (in terms of light) to cover a full frame sensor, (by some I mean the EF-S 60mm macro) I've seen shots from this lens taken through a 5d using the extension tubes trick and though the tube would help a little bit, it still showed no "hard" vignetting. I would be concerned that the lens design would not have taken into account all the superfluous coverage outside the area an EF-S camera can use, so there might be very little correction involved for the quality one might typically expect, no real idea though.

Photoskipper

Robinivich wrote:

Some of the EF-S lenses will actually produce an image large enough (in terms of light) to cover a full frame sensor, (by some I mean the EF-S 60mm macro) I've seen shots from this lens taken through a 5d using the extension tubes trick and though the tube would help a little bit, it still showed no "hard" vignetting. I would be concerned that the lens design would not have taken into account all the superfluous coverage outside the area an EF-S camera can use, so there might be very little correction involved for the quality one might typically expect, no real idea though.

I am not sure. I tried my friend's EF-S 60 mm marco on the 5D but it does not fit. May the TC addressed the problem.

claudermilk

Tee Why wrote:

Only Canon makes an EF-S mount for lenses that have a smaller image circle made for APS-C sized sensors. Hence you cannot mount a EF-S Canon lens on anything other than a body that has a EF-S mount. So while the Canon 10D has a APS-C sensor, it has an EF mount and will not accept an EF-S lens.

All third party makers who make lenses for APS-C sensor (hence a smaller image circle) use EF mounts. Hence they will mount to any Canon slr that uses an EF mount. But since the image circle is smaller, placing such a lens will produce vignetting till you zoom back if you mount it on a full frame body or a 1D series which have a 1.3x crop factor.

Sigma denotes the smaller image circle with a DC, Tokina with a Dx, and Tamron with a Di II.

The little dot on the lens barrel is used to show where the EF mount needs to be aligned and is not color coded. Sigma uses white, Tokina uses white, and Tamron uses red IIRC.

Canon uses the red dot for the EF and a white pyramid for the EF-s and they are actually on differnt location of the lens barrel as well IIRC.

This is a big area of confusion but basically if you have a EF-S mount, it will work with both EF-S and EF lenses.

If you have a EF mount, it will only work with EF lenses.

IF you have a sensor larger than a APS-C and use a lens that is made for APS-C sized sensor, you will get vignetting irrespective of the mount of course.

That is my understanding as well. However, I do have to say my Tokina 12-24's alignment dot is red--and anoyingly on the face of the mount rather than the barrel. Need to do something about that...

jgoetz4

claudermilk wrote:

That is my understanding as well. However, I do have to say my Tokina 12-24's alignment dot is red--and anoyingly on the face of the mount rather than the barrel. Need to do something about that...

Good Morning,
A black Sharpie should fix that problem
Have a good day
Jim...

jgoetz4

Photoskipper wrote:

I am not sure. I tried my friend's EF-S 60 mm marco on the 5D but it does not fit. May the TC addressed the problem.

Good Morning,
I know of some people that have taken a hack saw and cut off the 'extended piece' to make it compatible with ff cameras. Don't think I would want to try that on a $600, 10-22mm ef-s lens :nono
Have a good day
Jim...

jgoetz4

ziggy53 wrote:

If the lens mounts and does not conflict the mirror (be very careful about this), you can expect that exposure may be affected and that auto exposure may be limited because of the strong black "frame" created from the extreme vignetting.

Morning Ziggy,
Kinda like 'Holga camera effects', which may be interesting or fun just to experiment with, provided there is no mirror conflict.
Have a good day
Jim...

claudermilk

jgoetz4 wrote:

Good Morning,
A black Sharpie should fix that problem
Have a good day
Jim...

Yup, I was thinking a dab of red paint--more visible on the black barrel. I'm doing pretty good as that's my main irritation with the lens.

Robinivich

Photoskipper wrote:

I am not sure. I tried my friend's EF-S 60 mm marco on the 5D but it does not fit. May the TC addressed the problem.

EF-S lenses have a little rubber ring at around the rearmost section of the lens mount that protrudes too far for it to fit inside EF mount cameras, it's designed to stop people mounting them by mistake, or trying to do exactly what we're looking at doing. The mark II extension tubes that canon makes can accept both EF and EF-S lenses, but have an EF mount to connect to the body, so they work like an adapter. You lose infinity focus (who cares, it's a macro!) but the lens can mount in this way. I think, based on the site I linked to earlier, that the EF-S lenses speak a slightly different language, so aperture and AF won't work.

As Jim said, you can also remove the little rubber bit. There's a reason for all this sophistication though, canon takes advantage of that smaller mirror to make the lens designs easier, this means the lens might be sticking in far enough to shmuck the mirror on a 5d, so why use a hacksaw on an $800 lens so you can bust up the mirror on a $3000 body where it won't even cover the whole sensor? I can see that the macro might be fun, but otherwise I can see no point in the whole exercise.