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11-03-2011, 11:11 PM   #16
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i actually ordered a whole set and got it on the second try. i had bought some calipers to try to measure the stock shim first, but that was a waste of time.

11-03-2011, 11:14 PM   #17
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Originally posted by dragon132312 when the screen looks in focus and indicates that its in focus , they are all front focus and the faster the lens the worse it is .


GregK8 They all FF the same amount, you just notice it on the fast lenses because of the shallow depth of field. Stop them down and it will be far less noticeable.


I know it will look more in focus when stopped down , I have an A 50/1.2 which I like for the OOF effect , so i figure if i get the camera to focus as close a possible at 1.2 the the other lenses should be spot on.
why have fast glass if you cant use it , I could try shimming it my self if thats the problem with the focus.


11-04-2011, 05:29 AM   #18
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I had the same problem when I installed a focusing screen on my K5. Fortunately "focusingscreen" provided
a 0.25 mm shim and nice twizers with their screen. I swapped the original metal shim for their plastic one and focussing was spot on as a result (dust spots as well, ). The way to change the shim is nicely shown on their web site. So I guess your best bet is to order new shims in a range near 0.25 mm, make the change and hope for the best.

Last edited by fg-one; 11-04-2011 at 05:41 AM. Reason: syntax mistake
11-04-2011, 06:20 AM   #19
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I have made my own shims with different sized plastic sheets. My - focusingscreen provided 0.25 mm shim was backfocusing. And dust is really a problem when changing more times the shims, to find the proper one, its everywhere on the screen, prism and mirror.

11-04-2011, 08:06 AM   #20
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QuoteOriginally posted by eigelb Quote
I have made my own shims with different sized plastic sheets. My - focusingscreen provided 0.25 mm shim was backfocusing. And dust is really a problem when changing more times the shims, to find the proper one, its everywhere on the screen, prism and mirror.
yeah, i can tell some horror stories about repeated shim changing. Once the little latch didnt completely click shut and a few days later my screen fell out while i was shooting and banged around on the mirror. another time, the screen had gotten dusty from repeated shim swapping, so i thought it would be a good idea to blow off some of the dust with my canned air. i was holding the shim by the tab with tweezers and the blast of canned air shot the shim nearly across the room.
i have it down now, but those first couple of cameras were a real learning oppotunity...
11-04-2011, 08:34 AM   #21
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daniel

in reading the posts, you say that both the stock screen and the katzeye front focus?

did the stock screen front focus before the change?

I am a little confused, unless you had a shim drop out and failed to notice when you pulled the stock screen.

Also, does the camera AF correctly in optical (not live) view? If it front focuses badly for normal AF and it did not previously then it is not the focusing screen, but you have done something to the mirror. I don't want to scare you here, but AF is not focus screen dependant, but mirror dependant.
11-06-2011, 07:54 PM   #22
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Hiya Folks,

Yeah I suspect I was front focusing before with the stock screen. I did manage to use the A*200/4 but not usually at minimum focusing distance. And when I tested it it was with the K 50/1.2 at f1.2, so not much wiggle room there.

So shims, eh? I must say I hold out little prospects of getting this to work by myself. If it front focuses, does this mean it needs a thicker shim/more shims or thinner/fewer?
11-06-2011, 08:52 PM   #23
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QuoteOriginally posted by Lowell Goudge Quote
daniel

in reading the posts, you say that both the stock screen and the katzeye front focus?

did the stock screen front focus before the change?

I am a little confused, unless you had a shim drop out and failed to notice when you pulled the stock screen.

Also, does the camera AF correctly in optical (not live) view? If it front focuses badly for normal AF and it did not previously then it is not the focusing screen, but you have done something to the mirror. I don't want to scare you here, but AF is not focus screen dependant, but mirror dependant.

Yes, the problem is the camera was not originally calibrated with the proper shim. You don't notice it right away because the stock screen is hard to focus manually. In my case the shim could not have fallen out because the shim was too thick, not the other way around.
With the Katzeye screen you are able to focus precisely so the front-focus problem becomes more evident. You don't notice the front-focus problem with the original screen because you can't manually focus precisely on anything.
This has absolutely nothing to do with AF.
AF works fine. We are talking about manual focus.

11-07-2011, 06:32 AM   #24
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From where one can buy these shims?
I would like to avoid official Pentax dealers in Europe cause they have unreasonably high prices.
Ebay?
11-14-2011, 12:48 PM   #25
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I too bought a new focus screen (KatzEye w/ optibrite) and had a significant front focus problem. I sent the camera in to Katz for professional calibration and could not be happier with the result. The customer service was superb (thanks Rachael!).

BTW, Rachael told me that the front focus problem is quite common with Pentax cameras but she did not specify if it was only the K5/K7 or all of the DSLRs.
11-14-2011, 04:27 PM   #26
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QuoteOriginally posted by wjax Quote
I too bought a new focus screen (KatzEye w/ optibrite) and had a significant front focus problem. I sent the camera in to Katz for professional calibration and could not be happier with the result. The customer service was superb (thanks Rachael!).

BTW, Rachael told me that the front focus problem is quite common with Pentax cameras but she did not specify if it was only the K5/K7 or all of the DSLRs.
How long was it from the time you sent your camera to Katz until your camera was returned to you? Also, was was the fee for calibration?
11-15-2011, 05:36 AM   #27
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QuoteOriginally posted by wcchamp18 Quote
How long was it from the time you sent your camera to Katz until your camera was returned to you? Also, was was the fee for calibration?
I think the calibration was $65 which included cleaning the mirror chamber. Service took only one day. I had my camera back in exactly one week but that was because I chose 2-day express air shipping both ways which added significantly to the cost.
11-15-2011, 06:55 AM   #28
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If you have any trouble getting shims in Australia (I did in the UK, the Pentax rep here just ignored three emails) you can use the 'strips of post-it note' method (cut tiny strips from the sticky part of a post-it note).

The post-it notes I used were approximately 0.05mm thick (standard 80gsm photocopy paper is about 0.1mm), I used 3 layers when shimming my split screen. I stuck the strips onto the edge of the screen, rather than try to stick them on the frame. Worked well for at least two years (I've sold that camera now).
11-15-2011, 07:08 AM   #29
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I have not seen any comments back from daniel to say whether he had the problem fully resolved, but in re--reading the posts, he said he wiped the mirror. Regardless of how gently this was done, it could be the root cause of all the problems.

the mirror will impact both the viewfinder and autofocus because the autofocus takes light reflected off the mirror. Any misalignment of themirror will impact AF. In fact, somewhere there is a thread on the K10D where they discuss the fact that the mirror rest is only on one side, and over time, the AF drifts as the mirror continually gets non uniform load from hitting the mirror rest on one side only. I believe the K5/7 have a mirror rest on both sides as a result of this
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