Full Frame + Extension Tubes + EF-S lenses?

[rubo]

<p>Just thinking out loud here. Would the addition of (for example) a 12mm extension tube allow the use of EF-S lenses on a FF body?<br>

The downside would be (from what i can come up with) a strong vignetting and some additional magnification.<br>

But it should allow the use of EF-S with FF bodies, or am i completely off here?</p>

 

[tommyinca]

<p>Not exactly, but the real downside is the lost of everything but near macro focus distant.</p>

[alan_bryant1]

<p>At the-digital-picture.com, the 17-55/2.8 review actually includes a photo taken on FF with a 12mm extension tube - you can see it near the end of the review.</p>

<p>http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx</p>

<p>His comment: "With the help of a 12mm Extension Tube, you can physically mount this lens on a full frame body. But you probably will not want to. The image above shows the image circle as seen through this combination by a Canon EOS 1Ds Mark III. In addition to the heavy vignetting, AF does not work and the aperture information does not report to the camera. Even in MF mode, more hurdles remain - at 55mm, the 17-55 will not focus any farther away than about 7" or so in front of the lens. This distance rapidly decreases as the focal length is widened until the subject is against the glass and beyond this point no subject can be in-focus. It was a fun exercise at least - and now we know."</p>

[allardk]

<p>You could use them like you would use any lens on extension tubes. For macro. Most lenses cannot be focused far beyond infinity. You move the point of infinity focus 12 mm forward, so you can never get infinity in focus. Depending on the lens you would probably get a lot of vignetting too. But you could always crop the center part and still say it was shot with a full frame :-)</p>

[allardk]

<p>Reading Alan's quoted text I realize this is an excellent way to get a sharp photograph dirt that resides inside your lens. Works on crop bodies too.</p>

[tapani]

<p>I wonder how well the EF-S 60mm macro would work with extension tube on a FF body. Some vignetting presumably, but in some situations it might not matter, and in macro work loss of infinity focus is no problem. Might be worth a try if someone has the gear.</p>

[rubo]

<p>Alan, thanks for the link (i totally forgot about that article).<br>

Not disagreeing with the author (i frequent his website quite often), but AFAIR Extension tubes are compatible with EF-S lenses on crop bodies, so i fail to see why the AF, metering, etc would not work with an FF body.<br>

Maybe there is a newer version of the extension tube, because on canon's website in the "accessories" section for the new EF-S 15-85mm both the 12mm and 25mm are listed as compatible. And not only with the 15-85, but with a whole bunch of other lenses as well (and yes 17-55 is also on the list).</p>

<p>But again i'm just curious, not like i have an FF to test this with :)</p>

[mbkissel]

<p>The older extensions tubes will not mount EF-S lenses at all. The newer versions, the "II" models, will mount either. But I'm missing the reasoning here, Rubo...why would you want to do this? Is it just the curiosity factor, or are you considering one for a specific purpose? My guess is that it will work, even the AF on full frame, but I can't imagine the IQ will be all that great. </p>

[alan_bryant1]

<p>Incidentally the image circle problem is solvable.... sort of. All you need is an extension tube and a teleconverter. You can mount camera -> teleconverter -> extension tube -> EF-S lens. The teleconverter enlarges the image circle, so a 1.4x converter will make an EF-S image circle almost full frame, and a 2x converter will make it full frame. Teleconverters normally won't mount to EF-S lenses, but with the extension tube they will. This doesn't solve the focus problem, but you can reduce that by using a telephoto lens, like the 55-250. So 2X + 12mm extension + 55-250 will create a 110-500mm full frame macro zoom. The image quality will probably not be acceptable, and the f-stop range of f/8 to f/11 is definitely not acceptable, but it might be a fun experiment. The same trick on the 60mm macro could possibly produce usable (extreme macro) results - it would be 120mm f/5.6, which sounds promising.</p>

<p>I'm intrigued by the possibility of getting sharp photos of the dust inside lenses. I wonder if that would actually work.</p>

[rubo]

<p>Mark - this is mostly just curiosity. But it might be useful in an emergency also.</p>

 

[jorge_garcia1]

<p>Tried EF-S 17-55mm + Kenko DG 12mm extension tube + 5DmkII<br>

Everything works fine (AF, IS, aperture) , but as expected, strong vigneting and no focus past 20 or 25 cm from front of lens (vigneting similar to 8mm Peleng on APS-C body)<br>

20mm extension tube was needed to use Canon 1.4 extender (version I). No vigneting now. Horizontal field of view around 8 cm (sorry, handheld)<br>

With Canon 2x extender no AF but, sometimes, you obtain focus confirmattion if you manual focus. Horizontal FOV around 5 cm (two inches)<br>

As I have not been able to put some dust inside EF-S 10-22mm, I put a piece of paper over the front lens. Focus ring has no efect, but zooming to 14mm allowed me to se paper fibers.<br>

With 20mm + 2x I can see my fingerprints on the front lens (at 17mm). Now I know I need to do some lens cleaning.</p>

<p> </p>