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12-30-2008, 10:14 AM   #1
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Shims for Focus Screen in K10D?

I've finally narrowed down my focus issues with my K10D. I now can trust AF in daylight and know the approximate adjustment to apply for incandescent light, too.

Alas, I've confirmed that my Katz Eye screen shows an error with Manual Focus: I can focus with the split screen on a line in a focus chart and what is actually in focus is about 2-3 mm behind that point.

I understand that I can send my camera off to Katz Eye and have them do the reinstall with the proper shims.

I'm curious if anyone has done this re-shimming exercise on their own.

Thanks for the replies!

12-30-2008, 10:51 AM   #2
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Your K10D should not require shims. If it does, it is a manufacturing defect. Are you still on warranty by any chance?

Steve
12-30-2008, 11:00 AM   #3
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Most likely it is still under warranty, unless the Katz Eye makes that a violation of the warranty.

I'll put the old screen back in and see if the focus error is still there...
12-30-2008, 11:16 AM   #4
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paper shims

hey, i had the same problem - after all the adjustments after firmware downgrade, really learning to use the lenses, and trying a different magnifying eyepiece and the katzeye screen, it just had to be that the screens needed shims.

i ended up using thin slices of post-it note pad (the sticky part) on either side of the frame below the prism, then inserted the screen and closed the clip. worked great, and am now getting the focus i'd always thought was possible.

was it wise to use paper? was it wise to use the tacky part (worked well to position and hold it in place, but what about that glue?) i've heard of people using automotive shim stock, but since the paper was soft and i didn't know the correct depth, that's the way i went. just because it worked for me doesn't mean your shim will need to be that same thickness....

hint: be sure to put a tissue or lens cloth over the mirror while working, to prevent scratching if the frame clip falls....

12-30-2008, 11:25 AM   #5
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Good to see that someone else had this issue and was able to fix it without spending lots more $$.

Given that I'm experiencing a back-focus problem with manual focus, can someone who groks the SLR screen setup give me a hint to the placement of the shims? Which side of the screen should the shims be placed? On the lens side or the eyepiece side?
12-30-2008, 01:02 PM   #6
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my back focus with manual lens issue was fixed by putting the shims on the eyepiece side. i stuck the light-tak post it note paper strips to the back of the frame at the left and right side, out of view from the eyepiece. they stuck easily by pressing lightly with a tiny screwdriver (use plastic if possible to avoid scratches), then i placed the screen in it's dropped down holder and tilted the whole thing back up. be very sure it's actually locked in place, or the frame can drop back down while shooting and scratch the mirror. also suggest using a couple of nice bright desk lamps and some reading glasses to make it easier to work....

good luck!



the reason i didn't apply the paper to the screen is that the glue might have left marks on the mat screen surface, like oily finger prints do.
12-30-2008, 02:09 PM   #7
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I must admit I never shimmed mine and have not noticed a problem with my manual glass when reviewing my "real world" photographs.

Maybe mines out as well on the test bench kind of set ups, but for me it's not proven to be a problem, I guess lucky me.
12-30-2008, 02:15 PM   #8
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QuoteOriginally posted by kauaiguy Quote
hey, i had the same problem - after all the adjustments after firmware downgrade, really learning to use the lenses, and trying a different magnifying eyepiece and the katzeye screen, it just had to be that the screens needed shims.

i ended up using thin slices of post-it note pad (the sticky part) on either side of the frame below the prism, then inserted the screen and closed the clip. worked great, and am now getting the focus i'd always thought was possible.

was it wise to use paper? was it wise to use the tacky part (worked well to position and hold it in place, but what about that glue?) i've heard of people using automotive shim stock, but since the paper was soft and i didn't know the correct depth, that's the way i went. just because it worked for me doesn't mean your shim will need to be that same thickness....

hint: be sure to put a tissue or lens cloth over the mirror while working, to prevent scratching if the frame clip falls....
This is indeed a coincidence. My camera was front-focusing with the optical path. I removed the metal shim and also used post-it notes (the sticky parts) to adjust the shim distance.

12-30-2008, 02:55 PM   #9
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This is great info! I'll get out a pad of sticky notes and an x-acto blade and make some shims tonight.

Film at 11...
12-31-2008, 12:27 AM   #10
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Giving a report on how the paper shims worked:

After using some artists masking tape both on top and underneath the focus screen, plus removing the copper shim that was in place, I was finally able to get an understanding of what was the problem. The copper shim that was supplied with the camera is not thick enough.

I ended up using a single thickness of 3m post it tape cut into thin strips. I just had to smooth it down and the focus is dead-on.

Of course, as local humidity changes, I'll probably have to replace the paper.

Now that I know the approximate thickness, someday I'll measure the current shim and get a new one cut out of a slightly thicker material.

Of course, I had my trials with removing and replacing the screen about 6 times. I accidentally dropped it on the carpet floor. I was able to remove most of the fuzzies with judicious bulb blowing and a nylon brush. I guess my viewfinder looks more like my film cameras now!

Focus is spot - on. I'm hoping this will open up new abilities to trust my eye when getting a portrait or a macro shot.
12-31-2008, 10:29 AM   #11
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QuoteOriginally posted by smigol Quote
Giving a report on how the paper shims worked:

After using some artists masking tape both on top and underneath the focus screen, plus removing the copper shim that was in place, I was finally able to get an understanding of what was the problem. The copper shim that was supplied with the camera is not thick enough.

I ended up using a single thickness of 3m post it tape cut into thin strips. I just had to smooth it down and the focus is dead-on.

Of course, as local humidity changes, I'll probably have to replace the paper.

Now that I know the approximate thickness, someday I'll measure the current shim and get a new one cut out of a slightly thicker material.

Of course, I had my trials with removing and replacing the screen about 6 times. I accidentally dropped it on the carpet floor. I was able to remove most of the fuzzies with judicious bulb blowing and a nylon brush. I guess my viewfinder looks more like my film cameras now!

Focus is spot - on. I'm hoping this will open up new abilities to trust my eye when getting a portrait or a macro shot.
A job well done. It must feel wonderful now that you camera focus is spot on. Thanks for bringing this issue up and sharing your experience with us.

I have two bodies. On the K10D manual focusing is spot on with both the stock screen as well as with KatzEye. On the K20D with both types of screens I get front focusing. I think this is opposite type of problem that you had. You had to add shims to the the copper side. But I have to reduce it on the copper side. Now here is my question from you. How thick is the copper shim? Do you think I can remove the copper shim? Would that be too much reduction? I get about 8mm front focus when I try the FA 77mm at its closest focusing distance. It feels like about 2.5 feet or so. Any tips you can give me would be greatly appreciated.
12-31-2008, 12:35 PM   #12
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There is a way to remove the copper shim.

When you remove the focus screen and look up into the area where the prism is, you'll see the copper shim. Hidden deeper into the camera and to the left of where the catch for the focus screen lever sits, you'll see that there's a small metal tab. Do the same lifting motion and the copper shim will fall out. To put it back in, you'll have to lift the tab again, as it's not a "spring loaded" type where you can just press against the shim and have it snap in place.

You may find it easier to remove the copper shim if you stick something to it to pull while gently lifting that tab. Since I was using the sticky notes, it was easy to use them. I also was able to have the shim drop down with just gravity when I lifted the tab.

On a whim, I tried it without the shim in place and found that the actual focus point moved further away about 30 mm.

It might be possible to measure the shim with a micrometer and then get some brass stock from a hobby shop and cut a replacement. If you have a steady hand, it could be done with an xacto knife. If not, then you may want to have someone cut it out with a laser or something like that.

Eventually, I'll probably get a brass shim done like that.

In the meantime, I'm learning to like my dust bunnies and manual focus!
01-03-2009, 10:37 AM   #13
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I actually ordered some shims from Katz Eye as I wasn't brave enough to try cutting my own. I'm not sure what was originally in the camera, but my lenses were front focusing quite a bit. I swapped out the original shim for one that is 0.25mm in thickness. I now get a bit of back focus, but the center of the frame is close enough where I'm happy. When doing portraits I'll just have to remember to focus on the closest portion of the eyelid I guess. If I ever find someone with a micrometer I'll measure the original and see if a 0.30mm shim would be spot on (if the original is 0.35mm, for instance).

There is a friend also here on the forums and he had the same problem as me. He removed his shim and gently rubbed it on a lubricated knife-sharpening block to thin it. After a few tries he's gotten it reasonably close.
01-04-2009, 09:30 AM   #14
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You can order shims in different thicknesses from Katz Eye? I may have to do this as I don't trust my work with paper!

Did you call them directly or are these shims somewhere on their website?
04-08-2009, 08:55 AM   #15
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I am bumping this thread back up to see if anyone has a direct link they can provide for the focus shims on the K20D. Since I did not get a Katz-Eye screen I don't want to bother their tech support. But if I knew the part number they use for their shims I could just order directly from them.

My camera is front focusing somewhere in the 25mm range. If I am wrapping my head around this thread I am thinking:

Front focus = Too thick of a shim.
Back focus = Too thin of a shim.

So I guess I am also wondering if anyone has some extra shims from their installation. When I pull mine out I will mic it to see how thick it is. Then again is it possible the shims are labeled?

Depending on price maybe it would behoove me to order multiple shims rather than "guesstimate" what size I need.
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