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07-21-2016, 05:43 AM   #16
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I have observed what he has mentioned.

Lenses that have been with me for years and totally ok since K7, suddenly not getting infinity focus when set to the infinity mark of the lens.
My M85/2 ended up focusing only to no more than 8m.

My personal thoughts are that the tolerance of the flange distance has been changed on the K1 and the result with old lenses with their own (looser) tolerances is a stack up tolerance issue.
Incidentally, my 'newer' FA limited are all fine.
So the 'new' tolerance is within stack limits of more recent lenses but might not be for old ones.

However, I don't blame Pentax for it.
The lenses ARE OLD.
Who knows what they went thru and what type of looser limits were film lenses based on (since film itself is not flat)

For me, I just sent the few affected lenses for a long overdue servicing and infinity adjustment.
Lenses came back cleaned, lubed and at infinity right where it is marked on the lens.

No reason to blame Pentax.
I'd blame them if they had this issue with still in production FA, DA, DFA lenses, but the rest is a 'no case' imo.



There are also a few threads out there on this wrt the Nikon D800 if the OP would like to google for it.




BTW, I promised myself, not to visit DPR Pentax sub section anymore..


Last edited by pinholecam; 07-21-2016 at 06:24 AM.
07-21-2016, 06:14 AM   #17
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QuoteOriginally posted by pinholecam Quote
BTW, I promised myself, not to visit DPR Pentax sub section anymore..
For that promise and exhibition of Big Brain Thinking, Otis Squirrel just upgraded your account here to Site Supporter. He sends his congratulations and his highest award for Big Brain Thinking.


Compliments of the Otis Appreciation Society....appreciating the efforts of Pentaxians worldwide!
07-21-2016, 07:02 AM   #18
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QuoteOriginally posted by Digitalis Quote
Are you aware that it is pretty easy to adjust and calibrate infinity focus on M42, K,M,A lenses?
Are you suggesting an actual physical calibration for some lenses ? Not a In-Camera adjustment correct ?
Some of my older glass seems calibrated to not be able to quite hit Infinity sharply before I hit the oo hard stop.....is this what you are referring to ? Thanks.....

---------- Post added 07-21-16 at 10:05 PM ----------

QuoteOriginally posted by ogl Quote
Some of manual focus lenses fans give lenses to the master who could overhaul lens to make infinity with digital cameras
I have this problem with a couple lenses NOT being abe to hit infinity correctly and think one or two need adjustment as I hit the hard stop for OO just before the image is sharp.....quite sure of it actually. But WHO is the Master ? Eric Hendrickson ? Thanks....

Last edited by Dlanor Sekao; 07-21-2016 at 07:20 AM.
07-21-2016, 07:06 AM   #19
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QuoteOriginally posted by pinholecam Quote
My M85/2 ended up focusing only to no more than 8m.
Hi Pin,
That would mean the lens was forward of register by 0.913 mm. ( by v= u*f/(u-f) )
I don't know the manufacturer's tolerance on the K mount register of 45.46mm,
but expect it would be in the range of 0.02 mm.

I have the SMC Pentax-M 1:2 85mm out of storage here for issues on another thread.
I just took 2 photos with the K-01 on a heavy tripod with the lens at infinity stop.
K-01 indicates it is close to being in focus at infinity however this lens does not go through infinity
The distant conifers in centre are about 400 ~500 metre away, which is within 10 micrometer ( 0.01 mm)
of being at infinity for this lens

at f/2
https://app.box.com/s/n58phlu1znwq3dsthyi8prq9257eipbw
at f/8
https://app.box.com/s/kpojca8k446jh4x9yjg03l9lbn34zr7s


The Pentax K-01 has 2 advantages for lens testing.
-no slr viewfinder which can introduce focus errors compared to the sensor image
-less camera shake

It is obvious that this 40 year old lens is too blurred when used wide open.
I think some of the younger photographers have unrealistic expectations for using lenses at wide apertures.

07-21-2016, 07:16 AM   #20
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QuoteOriginally posted by Dlanor Sekao Quote
Are you suggesting an actual physical calibration for some lenses ? Not a In-Camera adjustment correct ?
Some of my older glass seems calibrated to not be able to quite hit Infinity sharply before I hit the oo hard stop.....is this what you are referring to ? Thanks.....

---------- Post added 07-21-16 at 10:05 PM ----------

I have this problem with a couple lenses NOT being abe to hit infinity correctly and think one or two need adjustment as I hit the hard stop for OO just before the image is sharp.....quite sure of it actually. But WHO is the Master ? Eric Hendrickson ? Thanks....
There are some specialists at Russian Penta-Club
07-21-2016, 07:23 AM - 1 Like   #21
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Normal, infinity calibration with a specific lens and camera body is routine calibration work for Pentax qualified service labs. A lab will tear the lens down, change the AF gear mechanism, mount the lens on the camera body on a test bench and tune infinity focus to the best achievable accuracy. Broadcasting this kind of problem over the web:
1) ain't going to fix the infinity focus issue
2) you look like needing to learn about how focus works
3) you don't follow a repair service process already setup by Ricoh imaging co.
4) eventually contributes to damage Pentax brand image while bringing no benefit for you, if this is your goal

Best regards.
07-21-2016, 07:41 AM   #22
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Cannot achieve focus

Well, then, how about a recent vintage 35mm DA ... ?

---------- Post added 07-21-16 at 07:45 AM ----------

QuoteOriginally posted by biz-engineer Quote
Normal, infinity calibration with a specific lens and camera body is routine calibration work for Pentax qualified service labs. A lab will tear the lens down, change the AF gear mechanism, mount the lens on the camera body on a test bench and tune infinity focus to the best achievable accuracy. Broadcasting this kind of problem over the web:
1) ain't going to fix the infinity focus issue
2) you look like needing to learn about how focus works
3) you don't follow a repair service process already setup by Ricoh imaging co.
4) eventually contributes to damage Pentax brand image while bringing no benefit for you, if this is your goal

Best regards.
I don't agree.

a) I have been buying cameras and taking photographs for 40 years, and this has never happened before.
b) when it happens with two out of three bodies, and six lenses, which ones do I "send in for service" and why should I have to service a brand new camera less than one week old?
c) I am not the only one, there are many complaints spread all over the place.
d) this is a critical problem - the camera was purchased only for a single purposes.
d) Ricoh is doing a great job of damaging their own brand, I don't need to help.

---------- Post added 07-21-16 at 07:53 AM ----------

QuoteOriginally posted by Adam Quote
Focusing on the stars in the night sky is undoubtedly tough and requires lots of patience, no matter what equipment you're using. In your second set of shots, both seem out of focus, albeit only slightly.

This really sounds like a lens problem more than a camera issue; minimally more evidence/testing would be needed to confirm things either way.

With regard to the problem you're describing, as you turn the focus ring, are you able to go past critical focus on both the left and right sides? Also, when shooting, did you have SR disabled?
I have been doing astrophotograophy for a long time. This is not "new" to me. So:

1) the problem happens on every lens tried, using MANUAL FOCUS on LIVE VIEW ONLY, I hit the infinity focus stop, limiting travel BEFORE I can achieve critical focus.
2) no, obvious mistakes like leaving image stabilization on, were avoided
3) two out of three bodies - six lenses, some purchased at some cost. some pentax new, some pentax old, some new third-party

This is not how I want to spend my hard earned money and time ...
4) many other reports of the same problem
07-21-2016, 07:55 AM   #23
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having read this thread I have checked my K5 with the 18-55WR lens, and it does go past infinity quite noticeably, the 50-200 DA standard lens I have has a much closer tolerance but still goes past. The camera has no problems finding focus at infinity so I believe the over focus in the lens is there, so there's no hard stop shock going to the focus motor when it's focusing on infinity.

07-21-2016, 08:01 AM   #24
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QuoteOriginally posted by ogl Quote
There are some specialists at Russian Penta-Club
It is not "just older glass" ... how about a recent vintage 35mm DA lens?

BTW, all of this is manual focus, of course. The lens hits the focus stop towards infinitty BEFORE critical focus can be achieved - every time ...
07-21-2016, 08:30 AM   #25
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This sounds quite odd to me. I have three Pentax DSLRs and all but one of the 'digital' lenses I have can focus slightly beyond infinty. I'm wondering whether some bright spark at Pentax decided to bring back the infinity focus at the end stop that some people seem to miss a lot. Except that such a thing is not practically possible with a DSLR. It wasn't either with film actually except that we were less demanding then it seems.

BTW the one exception is a Tamron 10-24mm wide zoom which I had dropped right after unpacking from the box which may possibly have some bearing on how it focuses. I have some old k-mount lenses as well but I haven't really checked how they focus at infinity.
07-21-2016, 11:03 AM   #26
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QuoteOriginally posted by pinholecam Quote
I have observed what he has mentioned.
How can you have AF issues with a pine hole camera ?
07-21-2016, 11:11 AM - 1 Like   #27
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QuoteOriginally posted by biz-engineer Quote
pine hole camera
Woody Woodpecker.....!!
07-21-2016, 12:34 PM   #28
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Not so funny if it happens to you.

I am done, out, thank you very much.

In parting, may I say that it seems strange:

1) IF your camera product is obviously oriented towards astrophotography with many cool features,

and,

2) IF your camera body is targeted towards existing Pentax owners with a collection of old and new pentax lenses,

THEN

why would you produce a camera that could not manual focus properly at infinity, defeating both goals. In particular,
monkeying around with the flange distance, etc. would be suicide in terms of Goal #2.

Well, I have wasted enough time and money. Back to Sony.
07-21-2016, 01:07 PM   #29
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QuoteOriginally posted by rcolman Quote
Not so funny if it happens to you.

I am done, out, thank you very much.

In parting, may I say that it seems strange:

1) IF your camera product is obviously oriented towards astrophotography with many cool features,

and,

2) IF your camera body is targeted towards existing Pentax owners with a collection of old and new pentax lenses,

THEN

why would you produce a camera that could not manual focus properly at infinity, defeating both goals. In particular,
monkeying around with the flange distance, etc. would be suicide in terms of Goal #2.

Well, I have wasted enough time and money. Back to Sony.
I think this should be considered a manufacturing defect and the dealer should give you a new and functioning replacement. If it cannot focus at infinity it is broken and I don't think they can argue against that.
07-21-2016, 01:08 PM   #30
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Most lenses focus past infinity. The lens infinity mark is indeed temperature dependent as well. The only way to critical focus a lens at infinity in darkness, particularly at wide apertures, is focus on the sensor itself with magnified live view. Use bright star or any other bright light at infinity to focus on.
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