Quest for a UV-capable wide-angle lens

[Alex H]

I do not know, John. Myself, I am well set with UV-lenses ranging from 28mm to 135mm, so my interest is only in ultra wide andle lenses, and, to a lesser extent, telephoto.

[JCDowdy]

Well, you mentioned that you were interested in 17-21mm, so the Canon FL-mount 19mm f3.5 & f3.5R were within that range.

The FL-mount ran from 1964-1971 so they might be of a vintage of simpler coatings.

I might try a 28mm f3.5 or 35mm f3.5 if one falls into my lap. Like I need another adapter!

[Alex H]

That's right. And I have considered the FL 19mm, but when I looked at it the prices were outside of my comfort zone.

[JCDowdy]

Yep, folks seem rather proud of them.

[rfcurry]

Alex,

 

Have you tried any Cine lenses? Prime cine lenses can be had for a modest sum and produce a decent image in UV if you don't object to cropping the occasional vignetting. Below are images taken with a full-spectrum-modded GF1 and a Som Berthiot (Paris) Cinor 1.5/17 lens. The UV photo was ISO 400, f8, and Andrea 'U' filter. Lighting was solar through a window. The visible image was f8, proprietary CC filter, and ISO 200.

 

 

The UV image below was cropped to remove vignetting.

 

 

regards,

Reed

[Alex H]

Reed, as I mentioned in the first post, I am looking for a wide-angle or ultra-wide angle lens to be used on a full-frame camera.

[rfcurry]

My apologies.

[Alex H]

Finally I was able to buy/borrow two more lenses and assemble this sextet:

 

 

I opted for "landscape" test shot since this is what I intend to use one of these lenses for.

 

These shots were taken with the same settings: ISO, aperture value, in-camera white balance (preset using Kyoei 35mm lens and PTFE), metering mode.

Early morning sunlight was not absolutely consistent but close enough. Besides, shutter speed values are not of major importance for me here.

I did adjust exposure, brightness and lifted shadows, but all changes were exactly the same for all pictures.

 

Lens names (and exposure values) are marked on images.

 

 

 

 

 

 

 

Taking into consideration that I am looking for the lens to use on full-frame camera body (Olympus lens is designed for half frame), here is my personal subjective rating of UV transmission:

 

21mm Bushnell (Tamron) - 20mm Vivitar (Kino Precision) - 21mm Super-Lentar (Tokina) - 17mm Vivitar (Tokina) - 20mm Flektogon (Carl Zeiss Jena)

 

Next step would be to compare lens performance on full-frame camera in visible and (when time comes) in UV light.

[Andrea B.]

Good test, Alex. Thanks for this interesting list of wides.

 

Am I correct in assuming that the filter must be placed on the rear of the lens with most of these wide angle lenses? Are you using a special adapter or what?

 

Too bad about the Flektogon, but it does seem to struggle with UV. Are all the lenses reasonably well made? They look clean as a whistle in the photograph, but appearances can deceive. (smile)

[Alex H]

Am I correct in assuming that the filter must be placed on the rear of the lens with most of these wide angle lenses? Are you using a special adapter or what?

 

All tested with Baader-U2, mounted inside the home-made adapter.

 

Too bad about the Flektogon, but it does seem to struggle with UV. Are all the lenses reasonably well made? They look clean as a whistle in the photograph, but appearances can deceive. (smile)

 

Sorry, but I do not understand this statement.

[Andrea B.]

I'm asking about the build of the wide-angle lenses - whether they are robustly built? Sometimes older lenses are made from metals and are strong and tough. But sometimes you see plastic parts, or the lens has not held up to heavy use over time.

[Alex H]

These lenses are from the 60-th and made from metal. Of course, if one tries really hard one can breake anything.

[nfoto]

Alex, you made me purchase a Tamron 21 lens No direct need for it, but so enticing.

[Alex H]

Alex, you made me purchase a Tamron 21 lens No direct need for it, but so enticing.

 

Sorry about that! Note that this lens has small rear-mounted UV-filter. To be honest, I never verified how strong it is at blocking UV, all my tests were done with this filter removed.

[JCDowdy]

The difference in the field of view between the 17mm and the others is considerable, quite striking how much difference 3mm of focal length makes. It is a compelling quest you have undertaken, you have me learning some new things. Here is an article I found instructive from the folks down the street from me which has a few photos of our Memphis river front and downtown.

Thanks Alex.

[Andrea B.]

I like Roger's insights and articles. Thanks for that link. It's one I had not read yet.

[JCDowdy]

Andrea,

Knowing so little about ultra-wide I read around a little and also thought this was fascinating:

The Top Five Most Extreme Wide-Angle Lenses Ever Built

 

Alex,

Do you think a Voigtländer Super Wide Heliar 15mm/4.5 would have any chance as a UV lens?

It is probably to modern but it sure looks pretty sitting on an Sony A7.

[Alex H]

Alex,

Do you think a Voigtländer Super Wide Heliar 15mm/4.5 would have any chance as a UV lens?

It is probably to modern but it sure looks pretty sitting on an Sony A7.

 

I can not answer this question, John.

[nfoto]

"Voigtländer Super Wide Heliar 15mm/4.5 would have any chance as a UV lens?"

 

When I think it over, I should have one of these floating around. Just need to return to my office to start looking for it ... Should fit on the GH-2 through an F-mount adapter.

[Alex H]

"Voigtländer Super Wide Heliar 15mm/4.5 would have any chance as a UV lens?"

 

When I think it over, I should have one of these floating around. Just need to return to my office to start looking for it ... Should fit on the GH-2 through an F-mount adapter.

 

So you have the F-mount version of it? Nice!

[nfoto]

Had the 12/5.6 and 15/4.5 both in M39 thread, plus the 15/4.5 in F mount with the F-S adapter. Just kept the latter for my 'S' rangefinders and the Bessa R2S.

[nfoto]

Just got the Tamron 21 mm f/4.5 in the door. Sample looks clean, but focus is off big deal in visible. Pretty OK for UV though.

 

The lens will need comprehensive modifications, though, as it is not compatible with an AI/AIS camera as far as metering goes. It needs a 'G' type CPU and/or a total rebuild of the mount.

[nfoto]

Meanwhile, still "good enough" for a UV selfie.

 

 

Nice to see the my blue eyes match the 'Fierce Bear of the North' concept :D

[Alex H]

Sample looks clean, but focus is off big deal in visible.

 

That can easily be adjusted. Focus ring is held by three small screws, which in later version of the lens are covered with rubber grip. These screws can be loosened and focus ring can be adjusted to match the infinity.

 

Did your lens come with rear mount filter? Removing it will also mess up focusing.

[nfoto]

The focusing ring is milled and engraving mark matches infinity. So adjustments have to be carried out internally I'd guess. In UV, the lens does go (+-) to infinity and the soft corners seen on my FX camera are cut off with the Nikon D3200 that currently hosts the Tamron.

 

No means of mounting a rear filter on my copy of the 21 mm and no sign it ever was possible.

 

I probably take the lens with me to Erik [Lund aka 'Dr. Lens'] on my next visit to him to get the weird bayonet mount replaced by something more appropriate. That'll facilitate upgrading the lens with a CPU chip as well. I found a spare 'F' bayonet in my bins that should be possible to use for the modification.