How I fixed my front focus

Madweasel wrote in post #11084577
Or did you miss the fact that he didn't miss the MkIII? It's the first in his list.

I did miss it! Thanks!

Does anyone know if the Mark II has the same size adjustment screws?

I did that with my 5d. Hardest thing is to make tool (that small hex 1.25mm). I spend few hours for attempts to get right size and shape . After that all adjusting process took 3-5 min.
To fix BACKfocus I`ve moved tool TO the logo.

Just tried it and it seemed to have worked! Went to Canon and another repair shop first and they wanted $100 just to have a look and quote on the repair. Not worth it as the the cameras probably worth $200-400.

Hi to all!
Thank a lot for the useful guide, i found it very useful. Unfortunatly I need the square allen key and I have not the ability to create the the needed tools..could please someone send them to me?
I've searched all around the internet, but I couldn't find something useful..

Thanks a lot for the all the helps in photography!

Hi all,

This operation also works on EOS 1Ds (MkI).
This kind of camera is too old to be repaired by the Canon center (at least in my country, they would't repair equipment older than 7y old).

Few months ago, this camera suddenly started to back focus without receiving shocks of any kind. This was odd and I could quickly realized while shooting shallow DOF portraits.
I had no clue what to do so I decided to learn how to manual focus .

After a while I discovered this thread and thought about testing this fix.
The screw that controls the AF is, as described for the 40D, on the right side very close (<1cm) to the sensor protecting film. This "screw" did not appear to have a hex nor a square shape but is rather circular. It is still possible (but hard) to turn it with an allen key or star key.
Anti-clockwise rotation corrected the back focus problem. Now the AF is as sharp as it should.

Thanks a lot for all the hints I could get through your threads.
In the hope this informations will be useful to other 1Ds users.

Cheers

Gee whiz. 10 pages of stuff and no one noticed that 1.25mm square = 0.049 inch. Now that I vist the Leatherman site I see that the multi-tool kit no longer includes the square 0.050 bit, but mine, which is 10 years old does.

John from PA wrote in post #14905793
Gee whiz. 10 pages of stuff and no one noticed that 1.25mm square = 0.049 inch. Guess what the Leatherman Charge Multi-Tool set includes a 0.050 inch Square Drive. I'm guessing it would fit fine.

How can you say that no one noticed the conversion between mm and inch? You really have privileged information about what every reader of this thread have noticed or not? I bet quite a lot of people are aware that 1 inch is 25.4 mm, without feeling a need to post that knowledge in this thread.

Next thing - most people haven't a Leatherman Charge Multi-Tool which means that they have no reason to make the same conclusion.

pwm2 "Sorry for being a noob"...I had noticed that someone stated the size was 1.25mm square and someone else mentioned they didn't have the tools to grind down an existing bit to that size. Excuse me for trying to be helpful.

John from PA wrote in post #14906054
pwm2 "Sorry for being a noob"...I had noticed that someone stated the size was 1.25mm square and someone else mentioned they didn't have the tools to grind donw and existing bit to that size. Excuse me for trying to be helpful.

And the best way you could think of was: "Gee whiz. 10 pages of stuff and no one noticed [...]"?

By the way - did you take the time to check where my title came from?

It's funny that this thread keeps being revived by first time posters

I know this is an old thread, but I'd like to post a concern. I have a 5d and an 85mm f1.8. My first copy had 1" back focus at MFD so I sent it back, got another 1 but same problem. Sent it to canon, came back and it was better, .5" back focus, sent it back again and it is not ok at close distances. However, I noticed while shooting our school intramurals that it tends to front focus at around 30feet but 5feet. Could this DIY fix that problem? Thanks

Has anyone tried this with a T1i/500D? I'm going to check for this screw, because both of my lenses front focus a bit (enough to be noticeable on some real-life shots).

Gracefully i can confirm that the method described works on canon 5d classic.
I used a 0.050" Allen Key to move the inside screws. Canon 5d has 4 screws, 2 screws inside, i suppose that the length of the mirror need an stopper in both sides, so you must screw both sides equally.

I can confirm that the screws are decentered and the propose is to stop the mirror millimetrically in the correct position. The inside screws controls the focus, and the outside screws fix the viewer accuracy.

The screw is had to move, but the focus change is very sensible, i first moved the screw 30 degrees more or less, and i was able so see the difference, after that i moved by 3 or 5 degrees (more or less) until i get the correct focus.

Be careful and do it by yourself.

Just got done adjusting my 5DC with a 1.2mm Hex Wrench. Had to order a pair online because you can't find these things at Home Depot or anything. Might be able to find them at a hobby shop or RC Shop. Got mine here: http://www.lazertoyz.c​om/12-MM-Hex-_p_222.html
Ended up being around $5 shipped. I even bent one about 45-Degrees to assist in turning since at some angles you can't get a good bite on the hex head.
Also confirmed- Moving toward the logo fixes Back Focus, Moving away from logo fixes front focus.
Seems to be spot on even wide open on my 85mm 1.4m.

P.S. Sorry to resurrect an old thread but this is very useful info. The alternative is sending it to canon for a $250+ service bill, which at this point is more than half the value of what these are going for.