NOCT Nikkor vs 50/1.2 AIS-- initial impressions

[james]

A visiting friend graciously lent me his NOCT (9-blade AIS-version). Both are at infinity focus on a D700, hand-held SOOC JPEG without modifications, ISO 2000, ƒ/1.2. Off-center, lower left and upper right crops follow. Note, the upper right crop is of buildings ~1.5 km away. Underneath the haze, the 50 demonstrates considerable inherent sharpness with less field curvature but the wild coma makes the image unusable. However, coma is far less pronounced on the distant objects from the upper right crop. The crops from the 50 seem sharper but this may be due to FC on the NOCT and/or slight focusing inconsistency on my part. Greater contrast from the NOCT does create the impression of higher resolution (see the center crop) but I can't say for certain.


Nikkor 50/1.2 AIS




off-center crop:





left lower crop:





upper right crop:






NOCT Nikkor AIS





off-center crop:




left lower crop:





upper right crop:

[sammo]

When you do tests with NOCT Nikkor, please try it also at f/2 and f/2.8 and compare with 50mm f/1.2 AIS lens. I have the 50mm f/1.2 and at f/2 there is no more coma (at least on cropped format), and it is very sharp, making it an excellent lens for such night shots (and also astronomy).
I wonder if NOCT could perform any better at f/2?

[james]

[sammo]

That would be great, thanks!
I always saw only comparison @1.2, never at slower speeds.

[james]

Reviewing the images, my suspicion is that there's really very little difference between the two at ƒ/2 and from what I read the 50/1.4G @ ƒ/2 exceeds both in terms of contrast and resolution. The NOCT, my friend tells me, weakens at ƒ/4 while the Super Fast 50 probably peaks thereabouts. I may try to push the ISO further to permit a hand-held comparison but do we really care about the NOCT or SF 50 at ƒ/2 or ƒ/2.8?

Coma does typically disappear at ƒ/2 on my 50 as does the haze. Resolution is first-rate. I've never used the 50/1.4G so I don't know how it compares. Frankly, I don't much care because I use a 24-70 for 50 and @ ƒ/2.8 it's hard to beat. I just boost the ISO a touch and make up for the 2-stop loss.

One thing I will say, both the SF50 and NOCT are challenging to focus in low-light without a split screen but the NOCT is even tougher. Can't say exactly why (?field curvature). Maybe it isn't such an issue with closer subjects. I used my friend's D700 since mine with a Katz Eye screen is out for repairs. The stock screen is just pitifully inadequate for fast lenses. I shot a CV 125 on his camera and it's the same issue. Nikon, always bragging about support for legacy glass, has rendered them crippled with no MF-optimized screen options. I have been told by Katz Eye that the newer FF bodies cannot accommodate 3rd-party screens without great engineering difficulty and prohibitive cost. Really a shame.

[sammo]

I care about f/2 sharpness, because for astronomy even the NOCT is useless at f/1.2
I never tryed Nikon's f/1.4G, but the ones I tryed (some, but not so many) were way inferior in sharpness at f/2 compared to 50mm f1.2 AIS.

[james]

[sammo]

[Bille]

What is tempting about the Noct is its unique signature, close to the f1 Noctilux or the Canon FL 58/1.2. And the compatibility with FX Nikons. As far as comatic aberration is concerned, I´d rather use a slower lens and tripod.

[james]

Been trying to upload the ƒ/2 images shot at ISO 6400 but am unable to, receiving all sorts of error messages. Even with the smallest files.

To summarize, what I have noticed is that for the 50, coma is now centrally defeated but still visible on the left (but not the distant right light sources) whereas purple CA persists on headlight sources. The NOCT is clear of all that.

[james]

Finally got the upload to work. Here are the ƒ/2 shots and crops.

Same scene as before, the crops are presented in series.

CENTER, Nikkor 50/1.2 @ ƒ/2




CENTER, NOCT Nikkor @ ƒ/2




LEFT, Nikkor 50/1.2 @ ƒ/2

[url=http://forum.mflenses.com/userpix/20133/big_1948_50f2left_1.jpg]
[/url]


LEFT, NOCTNikkor @ ƒ/2




UPPER RIGHT, Nikkor 50/1.2 @ ƒ/2




UPPER RIGHT, NOCT Nikkor @ ƒ/2


[/b]

[Esox lucius]

If

A) you have both a Noct Nikkor 58/1.2 Ai/Ai-S and a Nikkor 50/1.2 Ai/Ai-S

and

B) they are both up to factory standards ie. their infinity has been adjusted (they both focus by moving the whole lens assembly, if it is off-target then you will see more vignetting & CA at both near and infinity)

and

C) your methodology comparing the two is academically validated (ie. comparable)

then

at f/1.2 you will find out that the Noct is better, but certainly not the Holy Grail.

at f/2 the Nikkor 50/1.2 Ai/Ai-S will deliver better detail and contrast, clearly distinguishable at 100% detail view

at f/2.8 you will have an extremely hard time to differ them, if even possible

In other words, your 50/1.2 needs adjustment. It's a volume lens and very common for it to be "off-target" (I have had 5 samples pass through my hands and all but one needed adjustment). The Noct looks like it is delivering what it can, no need to send it for CLA.

Please keep in mind comparing these two lenses is unfair; they were designed for different use: Noct Nikkor 58/1.2 Ai/Ai-S was designed for people shooting star sky or landscapes hand-held with slow film. Nikkor 50/1.2 Ai/Ai-S was designed for medium to near focal lengths and street photography (in that area delivering better quality than the preceding 55/1.2 Ai Nikkor).

In other words, I concur with the findings in the diagram you posted.

P.S. I certainly would not pay more than about 500-600 EUR for a Noct Nikkor - any value above that is purely because of low production numbers ie. rarity.

[james]

Appreciate your thorough comments, Vilhelm. The NOCT was borrowed and had recently undergone a thorough CLA.
The shots were neither rigorous or exacting. They were hand-held and 'first impression' comparisons.

I am unfortunately unclear as to what I ought to tell the repair shop regarding what specific issues requiring adjustment with the 50. Poor central sharpness at 50? Lingering CA at f/2?

[Esox lucius]

If the serviceman is qualified, asking him to fix near and infinity focus and check wear on the helicoid is all you need.

See this story/topic for motivation why it's worth it

http://forum.mflenses.com/why-checking-infinity-and-servicing-lenses-is-worth-it-t39366.html

[sammo]

Keep in mind, that when you have pointy and high contrast light sources, there are usually two ways of focusing for fast lenses. One is to achieve best resolution. This way you have less contrast and more chromatic abberation (purple fringing). The other way is to focus to minimize chromatic abberation (you go slightly out of focus), this way of focus loses some resolution, but you don't get nasty CA.

[james]

[DanielT74]

I've just recently got the Noct-Nikkor, using it on the NEX-5n via the Alpa Speedbooster and the Nikon-Alpa adapter, to get the true 50mm field of view.

The positive surprise is that centre sharpness is much better than expected. I'd say that it is close to the Canon FD 55/1.2 Aspherical, th sharpest fast lens I've ever used. The negative is that the corners seem to be gone and vignetting is pretty strong which are probably due to the Speedbooster.

There is a lot of talk on the web that says that it is not sharp wide open. Looks plenty sharp to me...





100% crop:

[james]

I think the issue is that at ƒ/1.2 mis-focus is common in general because of the millimetres-deep DOF and more so when using a DSLRs focus confirmation alone. This, along with the dramatic FC close-up that must be understood, are probably the source of all the reports that the NOCT is 'unsharp'.

When I had my D700 with a split-circle focusing screen, my 'hit rate' for superfast lenses was really great, perhaps ~85% compared to 40-50% with dead-reckomning + focus confirmation dot alone (D800 included), especially in low light (lucky with 25% in the dark, sans split circle). Live view is sporting but toting about a tripod isn't practicable or feasible for many situations.

[Esox lucius]

I agree, there exists multiple times more lemon photographers than lemon lenses

[DanielT74]

[Bille]

[james]

[DanielT74]

[FotoPete]

[jimithing616]

I need to get me a f1.2 standard lens.... I have the gamut of 1.4's minus the nikon. Olympus om, canon fd, minolta md and mc, pentax m42 and K, Yashinon, you name it... gosh, I should do a comparison review when I get my NEX.