NikonGear'23

Gear Talk => Lens Talk => Topic started by: CardBoardBoxProcessor on June 22, 2017, 04:50:18

Title: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: CardBoardBoxProcessor on June 22, 2017, 04:50:18
Wonder what y'all thoughts are on these lenses. I have the Sigma. it is quite the lovely piece of glass. But I am starting to relaly love old Nikkor manual focus lenses. how would these 2 compare?
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: John Harkus on June 22, 2017, 22:34:01
I have a 20mm f/4 manual focus, and a 20mm f/1.8 AF - the MF is lovely, small, great engineering but can't compete in image quality terms with the newer model.
hth
John
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 23, 2017, 01:08:25
Unlike some members here (like "Longzoom"), I haven't found any decent sample of 20/2.8, MF or AF.  The (not too far) corners are always smeared even at f8.0.

On the other hand, I enjoyed my Ai 20/4.0.  Although the image quality was not up to that of the current AF-S 20/1.8 at the same aperture values, it performed way better than any of the 20/2.8s I have tried so far.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: CardBoardBoxProcessor on June 23, 2017, 02:11:50
Is that so?
I just did some testing of all my lenses. Assuming that they had the same image for all frames. At F/8 all my lenses are very sharp just as sharp as the Sigma. amazingly the sigmas is not as sharp in the corners as these old lenses.. at f/8. Very interesting.

the 20mm f/4 is appealing.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 23, 2017, 02:24:23
Yes, at least according to my own humble experiences.  Also recently I tried several Ais 20/2.8s at a Nikon specialist shop with my D750.  A few were maintained by a very reputable repair shop whose founder are retired Nikon tech persons.  Even such samples performed poorly at the peripherals (not the far corners) of the image frames at f8.0.

The Ai 20/4.0 I had wasn't super sharp but at least offered even image quality over the entire frame at f8.0.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: richardHaw on June 23, 2017, 03:53:54
I know the 20/2.8 AF-D very well. for many years that was my only landscape lens :o :o :o

to answer you, get a modern optic. the 16-35 f/4 is a VERY good lens at 20mm
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 23, 2017, 04:05:28
Akira, if you have friends in repair shop, ask them to open AFD or AF 20mm lens from the front side. (Be absolutely sure, that your lens IS NOT DECENTERED! In this case, do not even try!). They have a special pipe-key gears to perform that. Then, there is the special aluminum ring inside, by turning one left or right, not more than 1mm each step, you will find the optimal position to get an critical sharpness to extreme corners, at f4.0 - 5.6. It is extreme time-consuming operation, of course. Try 1mm, left. Put everything back, check. Better? Try 1mm more. Better? One step more. Too much? Back 1mm, you are done.  Or turn that aluminum ring to the right, the same operation. Perform it with the distance ring at infinity! At the first try, it gonna take you about 3 days. With some experience with this lens, next time gonna take 2-3 hours, not more. (BTW, you need to perform the same operation to clean the aperture, if needed. Never ever open this lens from the mounting back side!).  Do not know about Ais lens, have never touched one  to fix.  Good luck in any case!  LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 23, 2017, 04:18:23
LZ, thanks for your advice.  According to Bjørn, the AF 20/2.8 is rather vulnerable internally.  That's why I opted for the MF version.  Am enjoying your images, nevertheless.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 23, 2017, 04:25:00
Yes, of course, if you open it from the mount side! Your opinion on my images is very valuable, thank you so much! LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: CardBoardBoxProcessor on June 23, 2017, 04:41:40
Gosh people open and calibrate their lenses huh? Any before and after examples? One reduced tension on an MTO mirror lens and that made it so much sharper. but nothing like proposed here.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Øivind Tøien on June 23, 2017, 05:47:54
My AF 20mm f/2.8 (non-D) opened itself up from the front side a few times by itself. The front element which is part of the CRC mechanism tends to screw itself loose. If this happens the corners get very bad. I never noticed any screws inside it though so I guess one would have to go deeper for that adjustment.

My copy of the lens is very sharp at infinity in the dead center, more so than my 12-24mm at the same focal length. However the 20mm is inferior to the 12-24mm away from the center. On D200 the corners also showed strong CA, I have not used it much on later bodies.  It is possible that the high resolution in the center makes the less performing corners more obvious. Close up it is performing well but flares easily. I have the impression it worked better on film bodies. It did improve a bit after our local repair shop had a go at it again.

Here s to examples, the first at f/8, the second at f/10:

(http://otoien.zenfolio.com/img/s5/v124/p2384916277.jpg)


(http://otoien.zenfolio.com/img/s7/v153/p2384916278.jpg)
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: richardHaw on June 23, 2017, 08:02:36
on my sample, the complaint was more of a very "outdated" look.  :o :o :o
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 23, 2017, 11:57:55
Gosh people open and calibrate their lenses huh? Any before and after examples? One reduced tension on an MTO mirror(https://c1.staticflickr.com/1/665/31512009253_bb2e52bf32_b.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 l(https://c1.staticflickr.com/1/525/31512003923_4a384f6416_b.jpg) (https://flic.kr/p/Q1BfUt)2017-01-15 002-1-3 (https://flic.kr/p/Q1BfUt) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr(https://c1.staticflickr.com/1/478/32283961586_483f00be6e_b.jpg) (https://flic.kr/p/RbPK2m)2017-01-15 002-1 (https://flic.kr/p/RbPK2m) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickr
The Nikkor AFD 20mm at F4.0, after calibration. 2 Crops, from the center and extreme corner. For full resolution images, click on any sample to go to Flickr.  THX!  LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 23, 2017, 16:42:29
LZ, when I saw these images for the first time, I didn't notice the flare in the right below corner.  The image doesn't look smeared there, but have you figured out the reason for the flare?
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 23, 2017, 16:52:13
Not likely flare, because the Sun was back of me, covered by the buildings. So would you please make a screenshot and show it? Reflections from energy panels, maybe? Thank you!  LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 23, 2017, 17:08:37
I mean, the far right below corner of the second image looks a bit flared (or fogged) on my screen.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: richardHaw on June 23, 2017, 17:12:07
that looks as good as it gets  :o :o :o
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 23, 2017, 17:19:48
Aha, I see, Gentlemen! It is part of my brighten  window frame, from the right extreme corner side, making the foggy reflection, I believe! Yeah, there was no hood, my fault! Sorry for this event!  THX! LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: CardBoardBoxProcessor on June 23, 2017, 19:47:17
the corners are certainly very impressive. I'd be quite scared to open up a lens.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: David H. Hartman on June 23, 2017, 20:27:53
It looks to me like flare but the sun possition is wrong for the sun as the source. Could it be a touch of flare from the broad expanse of sky?

I've never thought of my 20/2.8 as more prone to flare than typical of a super wide. It's certainly not flare resistant like my 20/3.5 AI. I've notice some faint  flare with my AF-S 20/2.8G ED. I can remember if it was from sun or white clouds. When I bought my 20/2.8 AIS I checked Bjørn's legacy site and then checked for flare and ghost. That lens is so resistant I decided to keep it. I also bought a K-Ring set for close-up.

I like all three lenses. If I ever get my darkroom working again I'll want the 2.8 for shooting B&W with my F3. I won't sell my f/3.5 because of its flare resistance. The f/1.8 is my primary 20mm lens now.

Dave
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Akira on June 24, 2017, 02:45:18
During the film days, I used AF-D 20/2.8 on F100.  It flared very easily.  Around the same time, I looked into my friend pro photog's F3 with Ais 20/2.8, and it also flared very easily when a fluorescent light tube was right behind the top of the frame.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: richardHaw on June 24, 2017, 04:02:24
the ghosts are small but sometimes it can make something that looked like a batman symbol  :o :o :o the flare on the other hand contributes to the "outdated" look that I was talking about. i miss the lens to be honest.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Macro_Cosmos on June 24, 2017, 08:22:57
Why not consider the 20/1.8G or Voigtlander 20/3.5?  ;)
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: Øivind Tøien on June 24, 2017, 08:48:55
the ghosts are small but sometimes it can make something that looked like a batman symbol  :o :o :o the flare on the other hand contributes to the "outdated" look that I was talking about. i miss the lens to be honest.

Yes, photographing a subject with a bright background like a window behind can give this dreamy flare with the AF 20mm f/2.8.
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 24, 2017, 10:32:49
Exactly, like in this case! LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: mysh on June 26, 2017, 06:29:24
I have tried quite a few of the 20mm lenses from Nikon. I have tried the 20mm 2.8 AIS, 20m 2.8D AF, 20mm F4 AI, 20mm 3.5 UD. Overall I was never happy with any of them and found them to have glaring flaws. Out of all these I actually liked the 20mm 3.5 UD and 20mm F4 to be the best. I just never liked the 2.8 versions.

I did pick up the 20mm 1.8G when it was released and it changed my opinion of the Nikon 20s. The new 1.8G is an amazing lens and one I highly recommend. I don't know how it copares to the Sigma ART but it is lightyears ahead of the older Nikon 20s.

Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on June 26, 2017, 13:25:02
Agreed, out of questions! The new 20/1.8 is really best in the Nikon family (among 20-th). But we are speaking here how to get a dirty cheapo non-working  lens, fix it yourself to absolutely workable condition and post here sharp and contrast  images! To be honest, I am not in badly need of this old lens, but it is my little proud, what have I done with my own hands and knowledge to this peace of old glass, without real gears! It is fully workable photographic instrument now! Thank you for your comment, Mysh!  LZ
Title: Re: Sigma 20mm f/1.4 ART or Nikkor 20mm f/2.8
Post by: longzoom on July 01, 2017, 05:40:20
(https://farm5.staticflickr.com/4113/34832322223_f34675e29b_b.jpg) (https://flic.kr/p/V51KRH)2017-06-23 001-1-2 (https://flic.kr/p/V51KRH) by (https://farm5.staticflickr.com/4132/34832317493_c718707795_b.jpg) (https://www.flickr.com/[url=https://flic.kr/p/V51Jsa)2017-06-23 001-1-2-1 (https://flic.kr/p/V51Jsa) by longzoom (https://www.flickr.com/photos/longzoom/), on Flickrphotos/longzoom/]longzoom[/url], on Flickr.    It is the same lens in, almost, the same position, but at F5.6 now. The crop, from extreme corner. So, I believe, this aperture is an optimal for my copy of the lens. THX!  LZ