I just finished shimming my viewfinder. The camera shipped with what looks like a #12 and a #8 preinstalled.
First off I tried a 15 and it was damn close, just about 1mm (on the chart) front focusing. I noticed there's no way to make a #14!? I tried a #8 and #5 and it looks spot on with the combination of those two.
Also took the opportunity to replace the SI plate (I scratched it ages ago) and have a good blow in there with my blower. I now have a dustless, accurate and (relatively) beautiful viewfinder.
Just in case anyone was curious, the 5D washers/SI plate/focusing screens fit perfectly with the 5D mark II.
How do you get washers or shims from Canon? I'd like to try it on my 5DII to see if it will better the difference I'm getting between live view and viewfinder focus.
Well, after further Google search, the same cast of characters came up with the answer here.
This was Mike's post from November which I missed (didn't have my new camera then):
"Some folks have had some difficulty in tracking down focus screen shims from Canon. One reason they're hard to google is that Canon refers to them as "washers". There are eleven different shims, which vary in thickness. They do not come in a set; they must be purchased individually. Luckily, they're inexpensive (~$22 USD for all). I spoke directly to a Canon parts department rep yesterday and here are the part numbers (note that these are for the 5D...I neglected to ask if they were applicable to any other body). My guess is that the part number suffix pertains to the thickness of the washer in mils (again, in my state of glee that I found these things, I didn't ask that either):
Would it be possible to have this job done by a Canon service center? I know they don't like it when you use alternative lenses on their cameras, but one can always tell them it's for Canon lenses Not that I currently use any Canon cameras, but just curious.
Yeah, I was wondering if Canon would do it, or pass along the washers under warranty. It may simply be less hassle to get the washers and do it yourself. I'm not yet fully convinced the washers are a good idea for the 5D MkII, as they may harm the AF in my Canon lenses. I don't know enough about the AF and focus confirm to make that judgement. If you put a shim/washer under the focusing screen, does it alter the AF? Maybe so.
Question for me is, hypothetically, does changing the microfocus adjustment in the "adjust by same amount" mode (for all lenses on the 5DII) end up being the equivalent to adding a shim/washer to the focusing screen? It might be so.
If that were so, what Canon should do, in firmware perhaps, is have a baseline microadjustment level for all lenses, PLUS, custom adjustments for individual lenses that don't quite fit the overall baseline adjustment. That would be more handy than the washers, if the underlying assumptions were true.
erichard wrote:
Yeah, I was wondering if Canon would do it, or pass along the washers under warranty. It may simply be less hassle to get the washers and do it yourself. I'm not yet fully convinced the washers are a good idea, as they may harm the AF in my Canon lenses. I don't know enough about the AF and focus confirm to make that judgement. If you put a shim/washer under the focusing screen, does it alter the AF? Maybe so.
AF sensors are behind the mirror, so no worries about that
erichard wrote:
Question for me is, hypothetically, does changing the microfocus adjustment in the "adjust by same amount" mode (for all lenses on the 5DII) end up being the equivalent to adding a shim/washer to the focusing screen? It might be so.
If that were so, what Canon should do, in firmware perhaps, is have a baseline microadjustment level for all lenses, PLUS, custom adjustments for individual lenses that don't quite fit the overall baseline adjustment. That would be more handy than the washers, if the underlying assumptions were true.
Canon do have a baseline adjust for all lenses and then for individuals - try it.
Also AUTOFOCUS micro-adjust has no effect on manual focus lenses.
Yes, but isn't that either-or, not both? If your camera was generally out of specs by +5, I'd adjust it by 5, and then adjust individual lenses on top of that to customize. The overall camera adjustment (adjust all by same amount) would equate to a shim/washer if my theory is correct (but maybe it's not?).
If you look at that menu, only one item gets highlighted blue, and that's the one the camera uses until you change it, as I understand it.
Have you tried it with an autofocus lens? It has no effect what so ever on manual focus lenses, Canon clearly clarify that by calling the menu option AUTOfocus microadjustment.
Shimming only adjusts your viewfinder image, and doesn't effect what the camera thinks is in focus, only where the plane of focus appears to be in the viewfinder. AF microadjust conversely only adjusts what the camera sees as in focus, but has no effect on the viewfinder.
If your autofocus lenses are front/back focusing then use AF microadjustment.
If your manual focus shots are coming out front/back focused when they appear in focus in the viewfinder then you need to shim the screen.
The AF sensors are UNDER the mirror - nothing you do to the focus screen will affect AF. You can actually remove the focus screen and shoot with AF - did it once on my 1Ds2 for the hell of it.
The 5D/II are infamous for screen shimming to get accurate MF. 1 series is not an issue.
Micro adjust has - NO effect on MF (sadly..) focus confirmation.
We really need some stickies for these things....
Oh - +1 on removing screws and plastic plate. Use a magnetized screwdriver or just tape a small but strong magnet to the metal shaft of the right screwdriver. prevents either screw from dropping into mirror box. No deforming of shims required/risked.
Not that I currently use any Canon cameras, but just curious.
