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07-14-2016, 06:36 AM   #16
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QuoteOriginally posted by Wild Mark Quote
Yes, the adapter is too short.
I read somewhere that sometimes adapters are deliberately designed to focus slightly past infinity, which aids for 1) a lens which had not been calibrated 2) contrast-detection AF. But this seems to be way too short.

07-14-2016, 06:42 AM - 1 Like   #17
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Yes way too short. Something does not seem right to me. I have a similar adapter and lens and have used it on my dad's Sony a7r without problem. So I suspect your lens or adapter or both are to blame. We would be very keen to hear of your findings with the m42-k adapter on the ricoh.
07-14-2016, 06:47 AM - 1 Like   #18
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As reported above, many E adapters are designed to focus past infinity, to assure infinity can be reached with tolerance build-ups. Also, a small difference in tolerance will have greatest effect on a wide angle lens,as the lens movement to focus is shorter with wider lenses.
However, re-reading the OP, this does seem pretty far off. I've used both fotodiox and FOTGA m42 adapters on my A7. The fotodiox inner clearance can interfere with some fast 50 lenses so they won't hit infinity, but the FOTGA has been fine.

Last edited by TomB_tx; 07-14-2016 at 06:52 AM.
07-14-2016, 06:49 AM   #19
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QuoteOriginally posted by TomB_tx Quote
As reported above, many E adapters are designed to focus past infinity, to assure infinity can be reached with tolerance build-ups. Also, a small difference in tolerance will have greatest effect on a wide angle lens,as the lens movement to focus is shorter with wider lenses. Infinity might look fine with a 135 on the same adapter.
Yeah but this makes pre-focus and hyperfocal focus hard, and I am still trying to find a workaround for this.

---------- Post added 07-14-16 at 06:50 AM ----------

QuoteOriginally posted by TomB_tx Quote
As reported above, many E adapters are designed to focus past infinity, to assure infinity can be reached with tolerance build-ups. Also, a small difference in tolerance will have greatest effect on a wide angle lens,as the lens movement to focus is shorter with wider lenses. Infinity might look fine with a 135 on the same adapter.
And in the same post it mentioned that this will screw up lenses with special designs i.e. floating element.

---------- Post added 07-14-16 at 06:59 AM ----------

QuoteOriginally posted by TomB_tx Quote
As reported above, many E adapters are designed to focus past infinity, to assure infinity can be reached with tolerance build-ups. Also, a small difference in tolerance will have greatest effect on a wide angle lens,as the lens movement to focus is shorter with wider lenses.
However, re-reading the OP, this does seem pretty far off. I've used both fotodiox and FOTGA m42 adapters on my A7. The fotodiox inner clearance can interfere with some fast 50 lenses so they won't hit infinity, but the FOTGA has been fine.
My adapter has a wide inner flange, and I do suspect that this will not work with my 1:2/35 lens, as the lens seems to be off to the side of the camera.

07-15-2016, 07:06 AM   #20
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QuoteOriginally posted by Wild Mark Quote
Yes way too short. Something does not seem right to me. I have a similar adapter and lens and have used it on my dad's Sony a7r without problem. So I suspect your lens or adapter or both are to blame. We would be very keen to hear of your findings with the m42-k adapter on the ricoh.
Well I now have received the M42-PK adapter ring and I used it with my PK-NEX adapter to take a few test shots on my a5000 body. I will test the lens on the Ricoh later, though.

Infinity focus is reached right after the 5 meter mark but before the infinity mark. Considering that many E-mount converters focuses past infinity by design to tolerate a badly-calibrated lens and the seller of the lens claiming that the lens had never been taken apart, I do find this acceptable. Hyperfocal focus should be possible by compensating for the fact that the PK-NEX adapter focus slightly past infinity, and I will be taking the lens out tomorrow. Will report later on that.

Below are some test shots (right out of the camera, w/o post processing).
Attached Images
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ILCE-5000  Photo 
View Picture EXIF
ILCE-5000  Photo 
View Picture EXIF
ILCE-5000  Photo 
07-15-2016, 07:19 AM - 1 Like   #21
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Nice shots. You should be happy with those. When you shoot this lens, remember, the sharpness is best found stopped down. But wide open you get better critical focus. So working the aperture ring to your favour is a must for this lens.

If you shoot wide open you will need to do a little PPing to boost contrast. that will boost apparent sharpness.
07-15-2016, 08:06 AM   #22
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QuoteOriginally posted by Wild Mark Quote
Nice shots. You should be happy with those. When you shoot this lens, remember, the sharpness is best found stopped down. But wide open you get better critical focus. So working the aperture ring to your favour is a must for this lens.

If you shoot wide open you will need to do a little PPing to boost contrast. that will boost apparent sharpness.
I think I took these shots at f8 or f11 and I usually use nothing else than f5.6, f8, or f11 as I do pre-focus a lot. I usually focus with the lens stepped down to have an idea on the DOP. If I have to shoot wide-open I will definitely use the focus magnifier or the split prism.

---------- Post added 07-15-16 at 08:08 AM ----------

QuoteOriginally posted by Wild Mark Quote
Nice shots. You should be happy with those. When you shoot this lens, remember, the sharpness is best found stopped down. But wide open you get better critical focus. So working the aperture ring to your favour is a must for this lens.

If you shoot wide open you will need to do a little PPing to boost contrast. that will boost apparent sharpness.
I used the Vivitar 2.5/28 (Kiron) on my a5000 body before, but that lens suffered from a very soft shot wide-open and CA even stepped down. The Takumar should be way better at least from what I got today.
07-16-2016, 09:38 AM   #23
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QuoteOriginally posted by Wild Mark Quote
Nice shots. You should be happy with those. When you shoot this lens, remember, the sharpness is best found stopped down. But wide open you get better critical focus. So working the aperture ring to your favour is a must for this lens.

If you shoot wide open you will need to do a little PPing to boost contrast. that will boost apparent sharpness.
So what I found today was that the outer tube of the lens (the one with imprint and the filter threads) seems to be a bit loose and wiggles around, but the front element seems sturdy. Is this something serious enough that I should send the lens to the seller for repairs or is just somewhat expected with old lens?

Sincerely

07-16-2016, 04:17 PM   #24
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QuoteOriginally posted by butangmucat Quote
So what I found today was that the outer tube of the lens (the one with imprint and the filter threads) seems to be a bit loose and wiggles around, but the front element seems sturdy. Is this something serious enough that I should send the lens to the seller for repairs or is just somewhat expected with old lens?

Sincerely
That part of the lens has nothing to do with the focus mechanism. Being loose tells me the three retainer screws are not as tight as they ought to be. It also suggests the lens has been dismantled, providing further evidence that the focus mechanism may have been tampered with and/or incorrectly set. Hmmm perhaps the lens needs to be looked t more closely.
07-16-2016, 06:11 PM   #25
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QuoteOriginally posted by Wild Mark Quote
That part of the lens has nothing to do with the focus mechanism. Being loose tells me the three retainer screws are not as tight as they ought to be. It also suggests the lens has been dismantled, providing further evidence that the focus mechanism may have been tampered with and/or incorrectly set. Hmmm perhaps the lens needs to be looked t more closely.
Well the lens on my old Ricoh had its retaining screws came loose by itself. I don't know if Pentax lenses have the same problem.

On the Ricoh the split prism doesn't line up at infinity when pushed to infinity at wide open, but still has a small gap (much like https://www.pentaxforums.com/forums/22-pentax-camera-field-accessories/325823...ar-lenses.html), but fine when stopped down. Not quite sure what is going on. I am contacting the seller of the lens to see if he can offer any help.
07-16-2016, 06:17 PM   #26
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QuoteOriginally posted by butangmucat Quote
Well the lens on my old Ricoh had its retaining screws came loose by itself. I don't know if Pentax lenses have the same problem.
Not generally. I have noted the Takumar's to be quite resilient to this issue.

QuoteOriginally posted by butangmucat Quote
On the Ricoh the split prism doesn't line up at infinity when pushed to infinity at wide open, but still has a small gap (much like Pentax adapter, no focus to infinity with Takumar lenses), but fine when stopped down. Not quite sure what is going on. I am contacting the seller of the lens to see if he can offer any help.
OK I think you have diagnosed the problem. It sounds as though the helicoid is not set to infinity correctly. Easy adjustment, but requires the right tools and a camera. Definitely discuss with seller.
07-16-2016, 07:42 PM   #27
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QuoteOriginally posted by Wild Mark Quote
OK I think you have diagnosed the problem. It sounds as though the helicoid is not set to infinity correctly. Easy adjustment, but requires the right tools and a camera. Definitely discuss with seller.
Just talked with the seller, and he says that it is possible to calibrate the lens according to the PK adapter ring, and with some tolerance margin for different adapters. Seems he knows what he will be doing. Will report back next week.
07-16-2016, 08:34 PM   #28
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Cool. Let us know how it is done when you achieve a favourable conclusion.
07-19-2016, 11:15 PM   #29
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QuoteOriginally posted by Wild Mark Quote
Cool. Let us know how it is done when you achieve a favourable conclusion.
Got my lens back today. The seller told me that he adjusted the lens to focus slightly past infinity as a measure of tolerance. I installed the adapter and lens on the Ricoh first, and the spilt prism seems to be happy with the hard-stop infinity. On the PK-NEX adapter, infinity is reached wide-open at around the 5m mark, and considering that the adapter is probably short by design (which I cross-checked with my other PK lenses), this is pretty good.
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