Author Topic: Repair of the Nikkor 20mm f/3.5 Ai-S!  (Read 1524 times)

richardHaw

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Repair of the Nikkor 20mm f/3.5 Ai-S!
« on: November 30, 2017, 02:48:48 »

David H. Hartman

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #1 on: November 30, 2017, 06:28:55 »
A note on AI v. AIS: the AI has a 100 degree focus throw while the AIS has only a 70 degree throw. I don't think I'd care for the AIS on account of the short focus throw.

Dave Hartman

As usual the specs come from Roland's site. I own the AI and like it for its very low flare and no ghosts.
Beatniks are out to make it rich
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richardHaw

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #2 on: November 30, 2017, 06:59:45 »
A note on AI v. AIS: the AI has a 100 degree focus throw while the AIS has only a 70 degree throw. I don't think I'd care for the AIS on account of the short focus throw.

Dave Hartman

As usual the specs come from Roland's site. I own the AI and like it for its very low flare and no ghosts.

I would have gotten the Ai if I knew about this  :o :o :o thanks for the tip!

Roland Vink

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #3 on: December 03, 2017, 20:52:23 »
I also use the AI 20/3.5 for the same reason as above, that website is very useful sometimes :) :o :)
Since it is optically the same as the AIS, I imagine the AI is also simple to repair.
It is known for being less than perfectly sharp at infinity, but for landscapes where I usually shoot at f/11, the results are quite acceptable.

Jack Dahlgren

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #4 on: December 03, 2017, 21:56:09 »
A note on AI v. AIS: the AI has a 100 degree focus throw while the AIS has only a 70 degree throw. I don't think I'd care for the AIS on account of the short focus throw.

Dave Hartman

As usual the specs come from Roland's site. I own the AI and like it for its very low flare and no ghosts.

For 20mm the shorter throw of the AIS is not a significant hardship in my opinion.

richardHaw

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #5 on: December 04, 2017, 05:00:29 »
there is one quirk with this lens and that is it's a bit hard to nail the focus perfectly when you rely on the digital rangefinder  :o :o :o
there is a workaround to this

jpgrahn

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #6 on: December 04, 2017, 09:20:02 »
Well, tell us!
Please, please, with sugar on!

I have the lens. It is really small. Big difference to the modern 1.8/20 AF-S G!
Johan Grahn

richardHaw

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #7 on: December 04, 2017, 10:00:39 »
Well, tell us!
Please, please, with sugar on!

I have the lens. It is really small. Big difference to the modern 1.8/20 AF-S G!

well, in my experience as far as my sample is concerned. critical focus is achieved JUST when the dot becomes solid when you rack it from the left. Some lenses will do it from the other side. I think that this is "backfocus" or "frontfocus" manifestation on manual lenses  :o :o :o

for example, my NOCT will give you the best focus on my Df when you rack it from infinity and JUST when the dot lights up then that will give you a very sharp result wide-open. If you move it just a bit further then it's going to be off by a bit. I hope that I am making sense here...

by the way, I am still looking for your picture with Helga. I will mail it to you as soon as I found it in my iCloud ::) it got screwy after I upgraded!

jpgrahn

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #8 on: December 04, 2017, 20:39:20 »
Don't worry! No rush!
I wish I had had more time to spend in Tokyo checking out camera shops.
All the best
Johan Grahn

richardHaw

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Re: Repair of the Nikkor 20mm f/3.5 Ai-S!
« Reply #9 on: October 29, 2020, 10:45:22 »
https://richardhaw.com/2017/11/27/repair-nikkor-20mm-f-3-5-ai-s/

just rewrote this old article, added lots of new photos, too. :o :o :o