Quick test of the Nikon AI-S 24mm f2.8

[Timber]

Going through some of my old lenses I found my Nikon AI-S 24mm lens. It's been collecting dust in my drawer along with it's brother the 35mm f2.0 as I got the Sony FE 24-105 f4 lens (which is a beast) which beats both these old prime lenses in almost all aspects (except the wide open aperture).

 

My experience with the lens that it is only okay wide open, you definitely want to stop it down to f4. It has the typical vintage feeling in rendering, on both contrast and colours, which is good for portraits and street (IMHO), hence I kept the lens.

 

Last week I decided to give it a try in UV as it has 52mm filter thread just like my S8612 and I was surprised that it quite well performed in UV. Today I wanted to test my EL-Nikkor 80mm as I just got the necessary step up ring to be able to use filters with it, so I grabbed my favourite UV lens, the E. Ludwig Meritar 50mm f2.9 and the Nikkor 24mm along with the EL-Nikkor 80 (old) and 105 (old).

 

I have no flowers here so could not test it that way, so I just shot 4 shots with the same Manual settings with the white balance set with the 80mm EL-Nikkor.

 

The things I look for when testing a lens compared to a reference lens (in this case the EL80) are the following: exposure and white balance shift. With exposure the darker picture has obviously less transmission while with the same white balance the more yellow tinted picutre has a deeper transmission (and blue has lower). Since I don't have tools to create spectograms or any other tool to measure the UV transmission this method seem to me the most suitable and seem to work quite well. You don't have to accept or agree with my methods, but with the available tools this works for me all the time giving me a brief idea on a lens' performance.

 

So for the tests the following was used for all shots:

Camera: Sony A7II Full Spectrum

Filterstack: U360(2) + S8612(1.5)

Exposure: ISO3200, 1/25, f8.0

 

And the lenses:

24 - Nikon AI-S Nikkor 24mm f2.8 Serial 645394

50 - E. Ludwig Meritar (EXA) 50mm f2.9 Serial 1409452

80 - Nikon EL-Nikkor 80mm f5.6 Metal version Serial 960383

105 - Nikon EL-Nikkor 105mm f5.6 Metal version Serial 350684

 

 

The subject was the site where I work :) Sky was clear and the photos were made in a 5 minutes window at 1PM, so lights did not change. UV index was 7 according to the met.

 

Here's a comparison of crops with same white balance (set with the EL80)

 

As you can see the 24mm Nikkor is more blue, which means it's transmission is not as deep as the EL80, but not bad. It just slightly darker which means it's transmission is really not bad. I find the lens quite usable for UV, especially as it has a bright f2.8 aperture! Even if you want to increase the sharpness and stop down to f4.0 it's still plenty of light going through. I'd say if you are looking for a wide angle lens for your camera then this is a good choice. Since it's a native Nikon lens you can use it on Nikon cameras and still have infinity and you can adapt it to any other systems including Canon EF and all the MILC: Sony E, M4/3, Nikon Z, Canon M & RF and the L-Mount alliance. You might be able to get even better transmission if you remove the coatings from the lens.

The 50mm Meritar has a slight yellow tint which means it transmits deeper but as you can see the picture is darker, which means the transmission is not as good as the EL80. The lens is soft wide open but at f4 becomes quite good. It has 2 versions, the old silver one being much better build quality than the newer zebra, but apart from that they are exactlyl the same.

The EL105 seems to me very similar to the EL80 just a slightly little more blue (maybe a touch brighter) which means it's not reaching as deep as the EL80 but they have very similar transmission.

 

And now all the photos with white balance set and levels adjusted just to show what results you can get with the given lens.

Nikkor 24mm

 

Meritar 50mm

 

EL-Nikkor 80mm

 

EL-Nikkor 105mm (I noticed a bit late that the white balance is not set properly... sorry :P)

 

Hope this helps.

 

Ps.: The 35mm f2.0 Nikkor seem to transmit just very little UV, I will compare it later to my other 35mm lenses.

[Andrea B.]

Useful, practical lens tests. Thank you.

 

There is always the possibility that a non-dedicated lens used for UV is going to show some chromatic abberations because it is not corrected for UV. Have you ever made tests for that?

[enricosavazzi]

I can add one more test of the AI-S Nikkor 24 mm f/2.8, a comparison with the Enna Lithagon 24 mm f/4. The latter lens is at present the only 24 mm listed in the UV lens sticky as suitable for UV imaging.

 

Both lenses tested on Sony A7 II full-spectrum (with CWB set in sunlight with Baader U), Baader U, Bowens 1500Pro studio flash with original non-coated tube and shield. Unfortunately I cannot yet use a rear-mounted Baader U on the Nikkor 24 mm f/2.8, which is a must to avoid flare, different color casts in the center and periphery, and other problems. So I used a front-mounted 2" Baader U on the Nikkor, and a rear-mounted 1.25" Baader U on the Enna. I bypassed some of these problem by using only 1:1 pixel center crops.

 

AI-S Nikkor 21 mm at f/11, flash power=5 (each power unit corresponds to one stop). This is somewhat overexposed, but the center crop shows quite good detail.

 

Enna Lithagon 24 mm at f/11, flash power =5. Obviously underexposed (by 2-3 stops). The resolution of this center crop is not too different from the Nikkor, but the corners are much worse in the Enna.

 

Enna Lithagon 24 mm at f/11, flash power = 7. 2 more stops of illumination intensity (nominal) are not enough to compensate for underexposure. Some more detail is visible along the stems than in the preceding image, but the blue color cast is more evident and the image is still underexposed.

 

In conclusion, I would say the AI-S Nikkor 24 mm f/2.8 is a clear winner, besides being a lot easier to find and somewhat cheaper, and should be definitely added to the lens sticky.

 

Thanks to Timber for this useful discovery.

[Andrea B.]

I make a note under the Sticky about the Nik 24/2.8. Thanks to everyone for the input on that lens.

[enricosavazzi]

Useful, practical lens tests. Thank you.

 

There is always the possibility that a non-dedicated lens used for UV is going to show some chromatic abberations because it is not corrected for UV. Have you ever made tests for that?

There is indeed a detectable amount of axial chromatic aberration, a.k.a. "focus shift" between NUV and VIS, although far from being the worse I have seen, especially in an extreme wideangle.

The following are center crops reduced to 1/3 the original size (i.e. 1,200 x 900 pixels, reduced to 400 x 300 pixels), both shot at f/2.8. Focused in UV on the stamina of the flower at the center. No focus readjustment in VIS. Note that this is a worst-case scenario, i.e. shooting with the lens fully open in the close-up range (focus at 32 cm marking on the focus scale). Shooting at f/11 or f/16 would largely or completely hide this problem because of the increased DOF.

 

Image sharpness within the NUV range transmitted by the Baader U and lens is not detectably affected by axial chromatic aberration, and the image is actually very sharp where in focus.

 

 

[Mark Jones]

this is very nice. I was looking for a wide angle lens to use on an aps cropped body with 1.6x crop equivalent to 38mm.

keh dot com has an ugly one for about $94.