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10-18-2009, 04:18 PM   #1
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Adaptall 60-300mm cannot focus at infinity

Hi,

I have a Tamron SP 60-300mm Adaptall lens with a P/KA adapter and I noticed that it does not focus at infinity. I have made sure that it is screwed on (attached) properly, but no luck.

Has anyone had a similar problem with this lens? I use an istD.

thanks
Kev

10-18-2009, 06:27 PM   #2
Igilligan
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I have not notice that with mine, but it is only a few days old...


Are you sure the lens is sitting in the adaptal 2 mount properly? I have a dickens of a time getting those things back on right if I take them off.


Can you tell how far out it focuses? approx?
10-18-2009, 09:18 PM   #3
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It seems to be the worst at 60mm, less than 20ft. I thought that it may be because it is not attached to the camera properly, but it sure looks like I have it on right.
10-19-2009, 07:55 AM   #4
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QuoteQuote:
Hiroshi It seems to be the worst at 60mm, less than 20ft. I thought that it may be because it is not attached to the camera properly, but it sure looks like I have it on right.
Have you got the adpater attached to the lens properly? I use this lens on my K20d without any focus problems.

10-19-2009, 12:47 PM   #5
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I am fairly sure that the lens is installed on the adapter properly, the electrical contacts are working, and it takes good pictures as long as I can focus it. I guess it is the lens. I will have to research the possibility of adjusting it.
04-26-2011, 03:07 AM   #6
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QuoteOriginally posted by Hiroshi Quote
I am fairly sure that the lens is installed on the adapter properly, the electrical contacts are working, and it takes good pictures as long as I can focus it. I guess it is the lens. I will have to research the possibility of adjusting it.
Thread awakening attempt.
I have the exact same problem. It focuses to infinity at the 300 range but only about 20-30 feeet or so at the 60 range.
I opened it up to try to adjust this but theres no way I can get it to focus correctly at the 60mm range but I can set it so that it focuses perfect on the 300.

Since others claim they dont have this problem... What could it be?

I have tried with the Adaptall-2 adapter for Pentax K M and an older Adaptall-M42 adapter.
It acts a bit like a variable focus, but worse since it cant focus under roughly 120mm and that isnt how its supposed to be is it?
04-26-2011, 05:25 AM   #7
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The front of the lens is off one or more slots on the helicoil. Take off the rubber sleeve used to focus/zoom by sliding it off. Under there you will see a slot with one screw (may have green plastic around its base). There may be two or three others for fine adjustment of the focus but leave them alone. Carefully remove the screw (do this on a white sheet inside a roasting pan, for example). Place the lens inside vertically and then turn the focus slowly. As the lens extends, it will release from the helicoil. Mark that release position on the edge of the lens with crayon (a helper is nice to have). Turn the upper lens part a small amount towards the desired rotational direction desired (one helicoil notch will usually do). The upper part of the lens can then be threaded back onto the lower helicoil portion (it may be a little "fiddlely" but with patience they will mate together). Keep turning until upper part bottoms out. The opening for the removed screw should be visible in the alignment slot (you may have to rotate the upper part slightly). Replace the screw (a magnetic screwdriver head helps). You can then loosen the adjusting screws for fine focus adjustment (these are in a line at the bottom of the helicoil) for fine adjustment but this is usually not necessary. Slip the rubber ring back on.
Good luck.
04-26-2011, 06:02 AM   #8
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Thank you very much.
I did however take it all apart and back again and its still the same.
The front group glass is even hitting the glass group behind leaving a faint ring on the front group glass. Starting to think that it is that group that isnt seated proper?
I also noticed that the 1st group at the mount wasnt screwed in all the way.
I did loosen its 3 screws and screwed it all the way in and fastened the screwa again but Im not sure what difference that made. Perhaps that is just another way to calibrate it?

Ill see if I can give it another try later on. Right now Im just glad I got it all back together again


QuoteOriginally posted by JVi Quote
The front of the lens is off one or more slots on the helicoil. Take off the rubber sleeve used to focus/zoom by sliding it off. Under there you will see a slot with one screw (may have green plastic around its base). There may be two or three others for fine adjustment of the focus but leave them alone. Carefully remove the screw (do this on a white sheet inside a roasting pan, for example). Place the lens inside vertically and then turn the focus slowly. As the lens extends, it will release from the helicoil. Mark that release position on the edge of the lens with crayon (a helper is nice to have). Turn the upper lens part a small amount towards the desired rotational direction desired (one helicoil notch will usually do). The upper part of the lens can then be threaded back onto the lower helicoil portion (it may be a little "fiddlely" but with patience they will mate together). Keep turning until upper part bottoms out. The opening for the removed screw should be visible in the alignment slot (you may have to rotate the upper part slightly). Replace the screw (a magnetic screwdriver head helps). You can then loosen the adjusting screws for fine focus adjustment (these are in a line at the bottom of the helicoil) for fine adjustment but this is usually not necessary. Slip the rubber ring back on.
Good luck.


04-26-2011, 07:55 AM   #9
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QuoteOriginally posted by aliasant Quote
Thank you very much.
I did however take it all apart and back again and its still the same.
The front group glass is even hitting the glass group behind leaving a faint ring on the front group glass. Starting to think that it is that group that isnt seated proper?
I also noticed that the 1st group at the mount wasnt screwed in all the way.
I did loosen its 3 screws and screwed it all the way in and fastened the screwa again but Im not sure what difference that made. Perhaps that is just another way to calibrate it?

Ill see if I can give it another try later on. Right now Im just glad I got it all back together again
Aliasant: Post a request for help in this forum: Manual Lens: Usage (Page 1) - Manual Focus Forum There are many people in there who know this lens well==they may be able to help you.

JT
04-26-2011, 01:55 PM   #10
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QuoteOriginally posted by Jewelltrail Quote
Aliasant: Post a request for help in this forum: Manual Lens: Usage (Page 1) - Manual Focus Forum There are many people in there who know this lens well==they may be able to help you.

JT
Thank you JT
I did as you suggested.
I do suspect it to be the lensgroup under the front group that isnt seated proper. It seems to touch the back of the frontgroup just enough to leave a ring mark and that just cant be right.
04-30-2011, 04:44 AM   #11
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I got help from Glimavator and managed to fix the lens.
Thread here: Tamron SP 60-300m Model:23A Not focusing to infinity. (Page 1) - Maintenance & Repairs - Manual Focus Forum
04-30-2011, 09:46 PM   #12
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QuoteOriginally posted by aliasant Quote
Aliasant, the 2 posted pics @ MFF look great--you do good work. If my 23a ever gets out of alignment, I'm sending it over to you. Congratulations--btw, the shots this lens can provide make all of your hard work a trivial investment. I absolutely love my 23a.

Best!

JT
05-01-2011, 02:49 AM   #13
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QuoteOriginally posted by Jewelltrail Quote
Aliasant, the 2 posted pics @ MFF look great--you do good work. If my 23a ever gets out of alignment, I'm sending it over to you. Congratulations--btw, the shots this lens can provide make all of your hard work a trivial investment. I absolutely love my 23a.

Best!

JT
TY JT
Makes my heart a little warmer. ( its way to cold outside for bugs so I needed that )

I do like the results I get from the 23A when I nail the focus but unfortunatly that aint often... Its a very dark lens at the long range and almost impossible to ficus on the wide even with my katzeye.
Its also my own fault not having a well calibrated lens combined with a not perfectly calibrated focusing screen... ( might need to go from 0.25 to 0.3mm shims )
When I get back home I will try to fix those things and hopefully that helps with my focusing.
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