p.1 #1 · I dissected my lens today!-Lots of new photos
I disassembled my Canon EF 35-80mm f/4-5.6 III today. It only took 15 minutes +/- for the actual disassembly and it wasted a couple hours of my day playing with it. You can snag one of these on B&S for super cheap, and it makes a decent super macro lens compromise. And if you do the dissection and re-assembly with care, it can be put back into it's normal working order once again.
Here's how to do it using a set of jewelery screwdrivers:
1: Remove the the flat plastic ring on the front of the lens that says all of the lens info: "Canon EF 35-80mm f/4-5.6 III, Canon Inc., Made in Taiwan..." Just pry underneath it all of the way around until it pops up.
2: After that, the rest is quite obvious- you should see 3 screws which you should unscrew.
3: The front element group should pop out of place.
Focusing must be done by moving the camera/lens toward or away from the subject. Mine seems to focus at about 1 inch or so. The magnification is incredible. The DOF is SUPER shallow. I shot mostly using a tripod and higher f/stop: 8-16. I'm can't say this with confidence, but I would guess the magnification was at least 1:1, probably 1:2. The magnification of the orginal lens compared to the improvised lens is phenomenal. After playing with it for a couple hours, I put it back together, and it worked just like normal! If you have one of these laying around, or if you get one for cheap, then it is worth trying!
Edit: Adorama sells a used version of this for only 50 bucks. You can adjust the magnifications somewhat with the zoom.
p.1 #6 · I dissected my lens today!-Lots of new photos
I took apart the rear of my 400 2.8 to the point where I was ready to remove the AF assembly, but I stopped there, put it all back together, was working fine, and sent it to midstate camera. There is a lens or two that is loose causing some focus issues.
p.1 #7 · I dissected my lens today!-Lots of new photos
If anyone wants the photos, then send me a PM with your e-mail addy. I can't post them on FM because I don't have image upload. I have photos of the dis-assembly, and sample photos. I would be very hesitant to try this on a 400mm f/2.8 (or even an 18-200mm IS) . But since the 35-80mm is only worth a few bucks, and the assembly is quite simple I went ahead and tried it. If you have any cheap kit lens laying around that you don't use, then you could try doing this to it.
p.1 #8 · I dissected my lens today!-Lots of new photos
The 400 is surprisingly simple to take apart. Not many really small pieces to worry about as I found. I got to the point where I saw the AF motor and I took the tripod foot off.
p.1 #9 · I dissected my lens today!-Lots of new photos
Once you find the screws, it isn't that hard. They can hide the screws pretty well, but I'm getting used to where to find them: basically under labels, etc. I am pretty scared of losing the tiny screws though. When you took apart the 400, did you destroy the weather sealing?
p.1 #10 · I dissected my lens today!-Lots of new photos
No, it appeared that the sealing was mostly done with large mating surfaces (atleast near the back of the lens that I took apart) where lots of screws clamp down to big surfaces that are precision machined and won't allow moisture through. Other areas are held together with gigantic clamping rings that thread into the barrels.
p.1 #11 · I dissected my lens today!-Lots of new photos
That sounds like a very solid construction. The front element of my lens was only held in by three small screws. It would be VERY simple to replace the front element group, but I doubt they manufacture it for this particular lens anymore. It's got such a small value it wouldn't really be worth replacing, though. Why did you take yours apart? A repair attempt?
p.1 #12 · I dissected my lens today!-Lots of new photos
Dpic_arctic wrote:
That sounds like a very solid construction. The front element of my lens was only held in by three small screws. It would be VERY simple to replace the front element group, but I doubt they manufacture it for this particular lens anymore. It's got such a small value it wouldn't really be worth replacing, though. Why did you take yours apart? A repair attempt?
I heard a loose lens inside that rear section, but I got to a point where I was getting into some tricky stuff and figured I might as well just send it to midstate where they can do a thorough cleaning and calibrate the lens which I can't do.
p.1 #13 · I dissected my lens today!-Lots of new photos
You don't need image upload to add photos, or if you do I don't know how I came to have it. I just post the link to photos in my on line albums. The link is found in the properties tab of each on line photo.
p.1 #14 · I dissected my lens today!-Lots of new photos
I know you don't need image upload. The problem is, I only have a Dreamstime account (not Flickr, photobucket, etc.) which is meant for photography sales, so I couldn't have casual equipment photos on there.
p.1 #19 · I dissected my lens today!-Lots of new photos
Interesting... when zoomed to 80 is the working distance similar to a 90mm macro lens? To make sure I understand, you focus by physically moving the camera, so a macro focus rail would be desirable?
Dec 03, 2009 at 05:56 PM
Chris Beaumont Offline • • • • • [X]
p.1 #20 · I dissected my lens today!-Lots of new photos
Years ago I had a 35-80 on my 350D and I always found the sharpness incredible, especially given the price, the one I had was no less sharp than the 24-70L I have now (although some would say that's not saying much ) so this idea really appeals.
) so this idea really appeals.