NikonGear

Gear Talk => Lens Talk => Topic started by: richardHaw on December 16, 2020, 06:17:09

Title: 20/2.8ais
Post by: richardHaw on December 16, 2020, 06:17:09
i have always been curious about this lens...

i had the 20/2.8D for a couple of years and had shot MANY photos with it, mostly landscapes :o :o :o

while I like it a lot, i found that it is not as sharp as what id imagine a prime lens would be.

now, i have been hearing that the ais is much better optically...i also assume that they both have the same optics, how could this be?

can anybody confirm that the ais is indeed better optically? Roland, Eric? Bjirna? anyone? ::)
Title: Re: 20/2.8ais
Post by: Birna Rørslett on December 16, 2020, 10:16:50
The AIS is not perfectly identical with the later AF as the optics of the  latter was tweaked to function better for autofocusing.

The 20/2.8 AIS does best at fairly short distances, but is not bad for landscapes either. I used it mainly in an underwater housing for which its near-distance capabilities can be well exploited.  It has a propensity for flare that I could do without, though.
Title: Re: 20/2.8ais
Post by: longzoom on December 16, 2020, 16:54:09
(https://live.staticflickr.com/665/31512009253_c16e1a20e1_k.jpg) (https://flic.kr/p/Q1Bhun)2017-01-15 002-1-2 (https://flic.kr/p/Q1Bhun) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr.   This lens is among the sharpest ever but needs to be adjusted manually. First of all, be sure the lens is not decentered, even to the smallest amount, corner-to-corner. Then, after opening it from the front, adjust its floating compensation optical group. It is a very, very precise job, almost microscopic one, but possible. Will take you about 15-20 hours, without coffee, hah! The result is directly in front of your eyes. Taken at f 4.0. Good luck!  LZ
Title: Re: 20/2.8ais
Post by: John Geerts on December 16, 2020, 19:47:13
The 20/2.8 Ai-S is ideal for travelling for its size and general quality.  I like it.  Had the AF before, but prefer the Ai-S version.



Granville, France   August 2020
(https://nikongear.net/revival/index.php?action=dlattach;topic=2610.0;attach=45737;image)

Donville Les Bains,  August 2020
(https://nikongear.net/revival/index.php?action=dlattach;topic=9589.0;attach=45613;image)

Also France
(https://nikongear.net/revival/index.php?action=dlattach;topic=9573.0;attach=45542;image)

Den Haag, November 2019
(https://nikongear.net/revival/index.php?action=dlattach;topic=9001.0;attach=41903;image)
Title: Re: 20/2.8ais
Post by: pluton on December 16, 2020, 20:19:16
My copy of the AiS was very good, sharpness-wise; the best of the Nikon manual focus 20mm lenses in my experience. Seemed fine at long distance on the D3 camera. It had the most pronounced case of wave-type distortion from any lens I have ever used. More pronounced than the Zeiss ZF 21/2.8!
Title: Re: 20/2.8ais
Post by: richardHaw on December 17, 2020, 00:19:47
jeeeeeeez....

i dont want to be adjusting anything on the ais...

i just want to overhaul and document one :o :o :o

these still cost a lot in the used market, even for junk ::)
Title: Re: 20/2.8ais
Post by: Akira on December 17, 2020, 00:27:12
I have only unfortunate experiences with 20/2.8, Ais or AF.  I had used an Ais with my F100, but the peripheral areas are always soft, and the corners are always smeared.  Since then, I have tested around ten samples of Ais and AF on D750, but never found even a decent sample.  I have very good experiences with all of the previous 20s: f3.5 (52mm filter), f4.0 as well as f3.5 (72mm filter).

The quality of the images that have been posted by Longzoom look unbelievably amazing to me.
Title: Re: 20/2.8ais
Post by: Bern on December 17, 2020, 01:11:16
jeeeeeeez....

these still cost a lot in the used market, even for junk ::)

is $420 a good price for a brand new copy? its advertised as a discounted price in a local store.  :)
Title: Re: 20/2.8ais
Post by: longzoom on December 17, 2020, 01:12:03


The quality of the images that have been posted by Longzoom look unbelievably amazing to me.
[/quote]  m(https://live.staticflickr.com/4159/34489636381_94dd3cfe24_k.jpg) (https://flic.kr/p/UxJpi8)2017-05-12 023-1 (https://flic.kr/p/UxJpi8) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr (https://live.staticflickr.com/4179/34489630821_8b0f343ddc_h.jpg) (https://flic.kr/p/UxJnDg)2017-05-12 023-1-2 (https://flic.kr/p/UxJnDg) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr     Thank you, Akira! One more TECHNICAL image with the crop, to check color of this dinosaur.  F8.0, for DOF.  LZ
Title: Re: 20/2.8ais
Post by: richardHaw on December 17, 2020, 01:33:00
is $420 a good price for a brand new copy? its advertised as a discounted price in a local store.  :)

yes it is :o :o :o
Title: Re: 20/2.8ais
Post by: David H. Hartman on December 17, 2020, 08:12:10
The 20/2.8 AIS does best at fairly short distances, but is not bad for landscapes either. I used it mainly in an underwater housing for which its near-distance capabilities can be well exploited.  It has a propensity for flare that I could do without, though.

When I first bought my 20/2.8 AIS I was seriously considering selling my 20/3.5 AI. I checked your legacy site...

"This tiny lens is extremely well corrected for flare and ghosting; accordingly is the inside tip for nature photographers fond of shooting into the sun (I am one of those)."

This one sentence saved me from a major mistake. I had taken the flare resistance of the 20/3.5 AI for granted. I still own both lenses.

Thank You!

Dave

I like the 20/2.8 AIS because it can be hand held at low shutter speeds in low light and I can still get good results. The second shot was at 1/30th f/8.0...

Title: Re: 20/2.8ais
Post by: Zang on December 17, 2020, 15:29:54
Does anyone have experience with those Tokina, Vivitar, Tamron manual 17mm? How do they compare to Nikkor?

z.
Title: Re: 20/2.8ais
Post by: Akira on December 17, 2020, 16:38:12
Hmm...not only Longzoom, but also John and Dave found good samples...
Title: Re: 20/2.8ais
Post by: Birna Rørslett on December 17, 2020, 17:11:14
Add me to that list as well ... I like the 20/2.8 AIS quite well, but for me it is a lens that waxes and wanes in its frequency of use. Just compiled my usage pattern off the data base and apparently it has been used mostly for IR the last years.

I made a small collection of images below to show what the 20 can be used for. (the night bus in Amsterdam is ISO 25600 on the Df, by the way).

Title: Re: 20/2.8ais
Post by: mxbianco on December 18, 2020, 08:43:21
I would add to the comparison between the AIs and the AF-D 20/2.8 the fact that the AF-D is a plastic lens, while the AIs is the usual Nikon tank of a lens. When presented with both samples side by side in the early nineties, I had no doubt and chose the AIs.
It proved being a tank: it survived falling off my camera bag from a sea cliff in Andøya, Vesterålen, and caroming down the rocks it landed at the bottom. I had a hard time climbing down to recover it: only one of the rabbit ears was slightly bent, quickly straightened with pliers. Quality was good  before and after the fall...

Ciao from Massimo
Title: Re: 20/2.8ais
Post by: Zang on December 18, 2020, 14:38:39
Birna, the last picture is awesome :)

And I always thought I'll never get into underwater photography because of 200kg gear, traveling to Mexico, going 200m under the surface... :)

Cheers,
Zang
Title: Re: 20/2.8ais
Post by: Gerhard2006 on December 21, 2020, 03:10:28
This lens is among the sharpest ever but needs to be adjusted manually. First of all, be sure the lens is not decentered, even to the smallest amount, corner-to-corner. Then, after opening it from the front, adjust its floating compensation optical group. It is a very, very precise job, almost microscopic one, but possible. Will take you about 15-20 hours, LZ
How do you adjust centering and the front group? I thought all the lenses are in groups?
Title: Re: 20/2.8ais
Post by: longzoom on December 21, 2020, 16:04:55
If any lens is decentered, forget about it. Nobody can fix or adjust such a lens. About 20/2.8 AIS - remove front group, there is an aluminum waved lever inside. Easy-open 2 micro bolts on it, and by moving this lever left or right, 1/2 of mm, to the left, say, firstly, assembly the lens back and try the lens to infinity. Better - open it and move more. If it isn't as good as before - move to the right. Be ready to spend as much time as needed. This aluminum white lever is connecting to compensate optical group, which is the part of the front optical group, by turning the optics less or more. Be sure you know the very first, manufacturer's adjusted, position of the lever.   Be extremely patient with your microscopic steps, one-by-one! You will be rewarded with sharpness ever possible, after all! Good luck!  LZ   (You MUST have proper tools and skills!).
Title: Re: 20/2.8ais
Post by: richardHaw on December 21, 2020, 16:14:44
that sounds like the adjuster for the CRC  :o :o :o
Title: Re: 20/2.8ais
Post by: longzoom on December 21, 2020, 16:27:17
Yes, that is what I am telling you about, but through this particular lens only. Any and every other optical system needs its own findings and ways on how to be adjusted correctly. My old MF Noct, from the very first bunch, was precisely adjusted by half-diameter, 10 microns each, bronze-made washers.  LZ
Title: Re: 20/2.8ais
Post by: Steven P. on December 24, 2020, 05:19:49
I have owned the Af 2.8 & passed it on. I tried the Ais version and I didn't care for the IQ, & returned it. I quested on the 20's when i was building my Df sack, a small time, back.


I am quite happy with the tiny F4 & would love a pristine 3.5/UD
Title: Re: 20/2.8ais
Post by: Roland Vink on December 24, 2020, 06:04:21
I had an AIS 20/2.8 some years ago. When I compared it against my AI 20/3.5 it was sharper by about 2/3 stop (at infinity), which corresponds to the difference in max aperture. However I still prefer the AI 20/3.5 due to its smaller size, it was a better fit with other lenses in my kit due to the standard 52mm filter size. And at the apertures I typically use, it was sharp enough for my needs.
Title: Re: 20/2.8ais
Post by: richardHaw on December 24, 2020, 06:55:47
please let me find one for very cheap and glass in good condition...so i can document it :o :o :o

please santa...
Title: Re: 20/2.8ais
Post by: David H. Hartman on December 25, 2020, 02:41:02
please let me find one for very cheap and glass in good condition...so i can document it :o :o :o

please santa...

Being realistic I asked Santa for a lump of coal. That would be better than what I got last year.

Dave
Title: Re: 20/2.8ais
Post by: Nasos Kosmas on December 25, 2020, 11:25:17
I had an AIS 20/2.8 some years ago. When I compared it against my AI 20/3.5 it was sharper by about 2/3 stop (at infinity), which corresponds to the difference in max aperture. However I still prefer the AI 20/3.5 due to its smaller size, it was a better fit with other lenses in my kit due to the standard 52mm filter size. And at the apertures I typically use, it was sharp enough for my needs.
I also keep an 20/3.5 for the same reason but it is not standing so good compared to the new lenses in my D750
Light fall of  and resolution is getting worse in the corners
Title: Re: 20/2.8ais
Post by: Airy on December 25, 2020, 12:05:07
My 20/3.5 AI performs apparently very well at mid-distance (e.g. interior shots of a celebration). I have not used it so far outside for architecture or landscaping, because infinity is off and I'm struggling to adjust it.
The 20/2.8 AIS is fine, except for
- wavy distortion
- flare sensitivity
Besides, I stop it down to f/5.6 at least for distant subjects in irder to get some +/- uniform quality. With the 20/3.5 UD, the choice is even narrower (f/8 or f/11).
Title: Re: 20/2.8ais
Post by: Jack Dahlgren on December 28, 2020, 23:51:40
My 20/3.5 AI performs apparently very well at mid-distance (e.g. interior shots of a celebration). I have not used it so far outside for architecture or landscaping, because infinity is off and I'm struggling to adjust it.
The 20/2.8 AIS is fine, except for
- wavy distortion
- flare sensitivity
Besides, I stop it down to f/5.6 at least for distant subjects in irder to get some +/- uniform quality. With the 20/3.5 UD, the choice is even narrower (f/8 or f/11).

I've got a UD, the diminutive f/3.5, and the 1.8G. The first two have been sitting on the shelf since I got the 1.8G. Could the 2.8 be better?
Title: Re: 20/2.8ais
Post by: Birna Rørslett on December 29, 2020, 12:05:42
Different, but not "better". The AIS renders the image in a more soft and delicate manner. The 1.8G handles shooting into strong light sources (ie. sun) better and images have delivered with stronger contrast. I use both.
Title: Re: 20/2.8ais
Post by: David H. Hartman on December 29, 2020, 21:34:00
I have not used it [20/3.5 AI] so far outside for architecture or landscaping, because infinity is off and I'm struggling to adjust it.

Richard has a couple of articles of interest regarding the 20/3.5 AI, AIS...

Repair: Infinity Focus Calibration (https://richardhaw.com/2017/10/21/repair-infinity-focus-calibration-12/)

I set the infinity on a 50/1.4 AIS using a Nikon F5 with a DW-31 (6x) waist level finder. Live view at 100% should work as well as the 6x finder. I put the camera on a tripod and used a street light about 3/8 miles (0.6 km) away. The longer the lens the farther the test subject should be. Richard suggests communication towers on the horizon. I would not call setting infinity easy but it's doable. A camera repairman friend cleaned the oil fouled aperture blades of my 50/1,4 AIS and gave the lens back to me to calibrate.

Repair: Nikkor 20mm f/3.5 Ai-S (https://richardhaw.com/2017/11/27/repair-nikkor-20mm-f-3-5-ai-s/)

Hope this helps.

Dave
Title: Re: 20/2.8ais
Post by: Bent Hjarbo on December 30, 2020, 14:42:25
Just got around to take my 20/2.8 for a spin.
Taken f11 with my Df
I have som marks on the rear lens element , that should not be good, but this picture seem ok, both at close and far distance.
Title: Re: 20/2.8ais
Post by: Zang on December 30, 2020, 15:05:35
I Got a cheap 20/2.8 AF-D some time ago (some of you may have read that story).

Pictures are OK in general, but... If there is a bright object within the frame, I can observe severe glowing effect and the contrast loss is significant. The glasses look crystal clear. Did anyone have the same issue? Any clue about the cause?

Cheers,
Zang
Title: Re: 20/2.8ais
Post by: Gerhard2006 on December 30, 2020, 23:00:31
Yes this shot looks really good. I’ve gotten some nice shots with it this fall and I noticed the background blur or Bokeh is really nice as well. Regards Gerry
Title: Re: 20/2.8ais
Post by: Airy on January 04, 2021, 23:59:21
Df, 20/2.8 @ f/8 or f/11