Dead easy way to convert from EF-S lens to EF. AND BACK!

Discussion in 'Canon EOS' started by andrew_espinosa, Sep 30, 2009.

  1. I figure some may know this already, but this is just good knowledge to keep on spreading.
    Basically ef-s lenses only differ from ef lenses due to some additional rubber on the rear end of the ef-s lens. To convert it all you need to do is pull the rubber piece out. Here is what I found on the subject:
    Now you can use great ef-s lenses like the 10-22mm on your full frame lenses. With the 10-22mm, however, you don't want to zoom out past 12mm. Seems the 17-55mm ef-s works without a hitch.
  2. Crazy insane, but sounds fun. Think I'll get a second-hand 18-55 to try this for the heck of it.
  3. Actually, the 17-55 is rumored NOT to work. But please try it and report your findings.
  4. At risk of spoiling the fun, I will point out that the purpose of the rubber is to prevent damage to the larger mirror of full frame cameras, which may collide with the rear of an EF-S lens, if it should accidentally be mounted on a full frame body. Indeed I thought it was *will* collide, not *may* collide. But apparently there's a tiny bit of clearance there.
    The additional rubber is not the only difference between EF and EF-S. The primary differences are the smaller image circle, and less mirror clearance to simplify lens design in light of the smaller mirrors of crop-frame cameras.
    The flickr discussion is an interesting experiment, and it worked better than I would have expected - but I wouldn't recommend trying it unless you understand the risks.
  5. Great stuff. That's why I wouldn't buy a used DSLR via eBay.
  6. As Alan says, you may find your mirror may hit the lens if you try this. The 'S' of EF-S stands for 'Short' referring to the distance from the back of the lens to the sensor. Not enough room for the mrror of EF body vameras in some cases.
  7. Also note that the flickr post used a 1D3, which is still a cropped-sensor camera (APS-H). Doing this with a full-frame camera will vignette more, and carry additional risk of mirror damage.
  8. To give you an idea of a possible result, here is how it looks with my Tamron 17-50 f/2.8 mounted on an EOS 600 (film) body. Please note that the lens, although intended for crop bodies, can be mounted on any EOS body. The odd shaped vignette is caused by the lens hood.
  9. William Michael

    William Michael Moderator Staff Member

    "Doing this with a full-frame camera will vignette more, and carry additional risk of mirror damage."

    Doing this with any EOS camera that does not have an EF-S female mount**, will carry additional risk of damage . . . no matter what format that camera is . . . :)
    **designated by a White Square - as opposed to a Red Dot signifying an EOS Camera will accept the EF mount.

  10. @Alan: Yes you are correct, the lenses are different in other ways as well, I probably should have specified that the difference I was referring to was in regards to the mounts.
    @BJ/Alan/Colin: The lens hitting from what I have read is a very mild tap and typically just needs a reset of the camera.
    **BUT, for anybody even considering this, let braver souls do a test situation that matches your camera type to your lens type that you want to convert. Unless of course you are the brave type, and post your findings here, lol.
  11. This is not the first time this lens has been 'modified. See where a further mod helps to cut the risk of mirror damage.
  12. @Craig, sorry I read the info wrong on the 17-55mm, I thought he was saying it did work on it when he meant it the other way around.
  13. William Michael

    William Michael Moderator Staff Member

    "The lens hitting from what I have read is a very mild tap and typically just needs a reset of the camera."

    (Not sarcasm – just my relaxed writing style)

    From everything you have read - where?.
    How big a sample group is “everything”?
    If your sources are internet yabba yabba talk feasts where “experts” can hide behind screen names and perhaps have not done the tap tap dance themselves - I would be careful of your interpretation of a “mild tap” and the auto-reset capacity of the EOS camera . . .

    If however you could direct me to some reasonable, well controlled “test results”, please . . . I am interested.

    Also remember (I think I read correctly) the 10 to 22 was bastardized to meet a pro need as the 40D had carked . . . so it was kinda emergency time - I've done that type of thing too.

  14. Haha, yeah I know this particular situation was more for need than anything. In terms of findings, it has been internet research only. It was about a days worth well over 2 months ago when I read about the conversion so I don't have any direct links.
    My interpretation of it being a mild tap comes from canon saying you will crush your mirror. Even just 20 people testing this out I think is proof enough Canon overstated how detrimental the tap is. I don't blame canon as they marketed for a specific use and don't want to be liable for the people who either mess up their lens or their camera.
    Also, when you mentioned a "pro need" I am assuming this guy has experience in digging inside his lenses to even dare such a surgery. But then again, anything requiring you to yank out or cut at your multi hundred dollar lens or camera has a Do At Your Own Risk assumption to come along with it and cover all your bases before you test it out.
    One thing I would say for sure is don't continuously smack the mirror against the lens as that's asking for trouble. Smack prevention would have to be a high priority here. Remember kids, Crack is Whack.
  15. William Michael

    William Michael Moderator Staff Member

    Ah you have humour . . .

    Repetitive tapping is bad - yes

    and the mirror alignment - - - going whackoooo?

    Nice talking with you Andrew, It's dinner time here. CU later.

  16. Only fun stuff. Vignetting and the possible "mirror tap" aren't the only issues. Even if the lens doesn't vignette (e.g. in the upper zoom range of the 10-22mm) you get a terrible corner resolution. Does it make any sense to spend so much money for a full frame DSLR and then loosing its edge resolution by mounting an inadequate lens ?
  17. To begin with the 10-22mm is pretty highly regarded. Ken Rockwell himself says in his reveiw of the lens, that if he had any reason to switch from Nikon to Canon, this lens would be it.
    It's pretty close to L image quality (not build), but it will never reach the designation because there are no L designated ef-s lenses. Also, this hack would be most suited to those who started out on the crop sensor Canon's who not only don't want the extra expense of buying the majorly expensive L to go super wide, but don't want to have to either sell or leave the lens useless.
    I also agree with Ken though, if you have something really wide, you're best shots, or at least your favorite way of shooting, will be zoomed out, not zoomed in.
  18. One of the first EOS film cameras I bought was literally the first one--the Canon EOS 650. It cost about $30. I use this as a test bed for adapting Nikon, M42, etc. lenses to "full-frame" digital.
    As indicated, not all lenses that will mount on a APS-C body will clear the mirror on a "full-frame". If it hits the mirror of the 650, I know not to try it on my 5D. So far it hasn't damaged the 650, but if it did, I could buy another one for around $30. I highly recommend getting one of the early EOS film cameras anyway, just in case you want to shoot a little film and only have a hundred or so other film cameras to choose from.
  19. Yikes! I agree Frank Mueller in that the only thing this definitely convinces me of is to avoid used equipment
  20. Dead easy way to toast your focus screen, in my experience. Next bright idea?
  21. If you find an 1.4-extender that allows to mount EF-S lenses this is the way to go: Since the lens is not directly mounted to the camera, there is no risk of damage. Furthermore it will enlarge the image circle by a factor of 1.4, i.e. eliminating most of the vignetting. However, which extender would fit?
  22. Oh, it's possible to mount them...sometimes...And if you don't mind a black circle bordering your shots, that is. EF lenses have a different rear element to sensor plane distance. So why bother? Its almost as much a waste of time as buying a Nikon to Canon adapter and running Nikon lenses on your Canon. But some people do.
    If you are moving to full frame, then you need to move to EF lenses...period...Off to ebay you go with your EF-S lenses. Its almost the same with Nikon. So don't feel badly done by. Once you go to full frame, you will never go back.
    And for all we oldies who have a shelf of older EF lenses from the film days...its happy times ahead.
  23. Technically don't all images come from a big circle? In this case you would just have to crop it, which isn't exactly the most complicated photoshop function. Basically it's a way to keep a zoom beyond 16mm that you get with the canon L lens, as well as preventing you from having to buy a 3rd party lens when you already own this one when making an ef-s to ef transition.
  24. As for steering away from buying used equipment, this is expressly meant to be done so you don't have to sell your old equipment, so it wouldn't be ending up in the used market anyways. Win-Win! And 90% of my equipment is used or a very old generation model.
    • I own a $150 ball head I only paid $45 for and all it was missing was 1" length of comfort rubber.
    • I picked up two quick release plate setups for that ball head for $35 total when both combined new would have been over $80.
    • I bought a tamron 28-75mm + multi-coating Omega close-up filters for $250 total and it works great. New It's about $375-$495 depending on who you buy from, and then you don't even get the close-up filters.
    • I have a tamron 60-300mm adaptall-2 sp lens that I only paid $10 for. I then bought a 2x teleconverter to go along with it for $35, and a adaptall-to-eos w/ af confirm chip for $40 so now I have an equivalent 120-600mm lens with good image quality (albeit a slow lens) for less than $100.
    • And my last bargain is my tripod which came with an attached ball leveler I paid $75 for which brand new sold for $300+. The bubble levels have evaporated and part of the twist handle to raise the geared column snapped off, but two bubble levels are $15 total and I'm handy enough to DIY myself a durable handle later for less than $10.
    So in the end, I'm a huge fan of buying used when I only spent $515 for close to $1000 in equipmemt.
  25. Its almost as much a waste of time as buying a Nikon to Canon adapter and running Nikon lenses on your Canon. But some people do​
    Really? I use Nikkor lenses all the time. I'm used to manual focus, although my eyes aren't what they were, and unless you're in a hurry, stopping down to meter after focusing is no big deal either. I wouldn't try to shoot fast moving sports with a MF/stop-down lens, to be sure. I also use M42, Exakta, and P6 lenses and each has its use.
    Examples of usefulness:
    Nikkor 58mm f/1.2- low light where AF isn't so hot anyway. Used it for hand-held pictures in a pictoglyphic cave lit up with a generator and some lights. Flash was unusable because of reflections from glitter in the rock.
    PC-Nikkor 35mm perspective control lens. Works just fine all manually just as it was on the Nikons, and it's already in my kit bag so works fine on a 5D "full frame".
    Reflex-Nikkor 500mm f/8 (it only has one stop open or shut anyhow). On a monopod you can learn to focus very quickly for animal shots. on an APS-C body it's even longer.
    Vivitar Qdos Anaglyphic 3-D 70-210mm in a C/Y adapter. Nothing like it anywhere else, unless you roll your own.
    well I could go on, but if you haven't tried it, don't call it useless . Some of us make good use of more than just Canon lenses ;)
  26. Interesting how one thinks when your back is against the wall. I would have thought 4 images merged together may have been easier than butchering a smaller image circle lens for a larger format. But if pro will just get another lens later to keep tax down, x1.6 >x1.3 not a huge amount tho. certainly did not have backup FL. problably ok for a bit of fun ;-)
    G`day Bill, hope the dust clearin for you down there, got into everything this way
  27. William Michael

    William Michael Moderator Staff Member

    Chris: Hi!
    Red Dust everywhere - fine powder in everything - I reckon I gotta buy a couple of new lenses just in case of damage - and to keep that tax down.
    I hope you bought that car, new and before June 30 to get the full benefit
    Cheers and beers,
  28. It may be easy but I'm not willing to risk my gear. Call me chicken, I wouldn't care, but I'd rather buy a 11-16/2.8 instead.
    Happy shooting,
  29. Just a few points regarding this modification to the 10-22. First, it may be accomplished without the use of pocket knives or pliers shown in some of the linked references. If you adjust the lens out to 22mm you'll be able to insert your finger through the hole in the rear baffle and pull it out. There's even a lip around the hole to help with gripping. Much easier and safer than the other methods shown.
    Also, the rear element doesn't protrude beyond the rear metal flange until somewhere between 12 and 14mm zoom. The distance from the rear metal flange to the mounting surface on the lens appears to be the same as with EF lenses, approx. 0.21 inches, so it would seem a good reference point for determining how far the rear lens element is extending into the body when comparing EF-S and EF lenses. On a 20-35 EF lens the rear element actually protrudes beyond the rear flange at the wide end, indicating that contact of the 10-22mm zoomed to 13mm or longer is very unlikely. It's also worth mentioning that the viewfinder displays noticeable cropping in the corners at anything wider than 14mm, so if one insures to zoom so that no cropping is visible in the corners when composing the picture the mirror shouldn't be contacting the rear lens element of a 10-22 EF-S mounted on a FF body. The risk seems minimal, aside from potential user error of not paying attention to the corners. For the occasional ultra-wide shot where corner-to-corner sharpness isn't critical it's an option.
  30. Tried Stephen suggestion, works fine but I will continue with Sigma 12-24mm for ultra wide.
  31. It's much easier to mount a Sigma 10-20mm on a 5D, if that's what you want than it is to mess with a Canon 10-22mm.
    The Sigma mounts without any modification on 35mm sensor cameras, and vignettes like crazy, which raises the question of why?
  32. Great stuff. That's why I wouldn't buy a used DSLR via eBay.
    No, that's why you pay full retail and resell it to me for a fraction of the cost. You're gambling a small risk versus paying pennies on the dollar. And it's only a gamble if the seller won't give your money back, which is unusual. The feedback system works. If it doesn't, you can reverse the charges on your credit card.
    This notion that the internet is full of nefarious rip-off artists that damage their equipment in bizzare and exotic ways so they can joyously resell it to you is pretty antiquated. Frankly, it's also a little egotistical.
    99% of the sellers out there are just like you and me: They have a camera, and they want to sell it.
    The other 1% has bad (or too little) feedback.
    -Paul B. Davis
  33. Just adapted my 18-55mm kit lens to work on my non-efs using
    I took the mount off the camera, put the hacksaw in the vice, and worked my way cutting the extra material off. Not the cleanest way but it worked and only took a few minutes all together.
    Worked great but left a good sized gap that I'll probably make a plastic cover for to keep dust out. Tried the lens out on an old Rebel X and its usable from about 22-55.
  34. Just in case anyone on here thinks they can slap an EF-S 10-22 onto a 35mm Canon EOS620 or 650, it won't fit.

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