Any telephoto fast near UV capable lens?

[colinbm]

@Avalon I have used one of these 70mm quartz singlets, you get 2 with the order.
From Israel....eBay item number:184886019447

My post about it....

 

[Stefano]

I have designed some fused silica lenses, I posted three designs so far. They use commercially available elements. Here's one: 

 

[StephanN]

4 hours ago, ulf said:

If you are really lucky you might find a mirror lens that have survived and still are sharp, if it ever was sharp, from the beginning.

 

[...]

 

I must confess that I have never used a mirror lens and what I say above is what I have read about only. 

 

[...]

 

 

Well, as shown in the threads at least I had the good fortune to find a reasonably sharp copy, without hunting around. Prices have gone down apparently, you can find an old Russian 500mm on EBay for 150 €, and even the 1000mm for around 200€.

 

However, Ulf is right, of course, mentioning the effects of athmosphere, but that's relevant for ALL tele-lenses.

 

About the doughnut bokeh, I think that this property of mirror lenses is bad-mouthed too much, definitely for UV/IR-use. If you're looking for the standard long view of cityscape or landscape, no night-shots with lights in the background or macro-shots, I don't think that you'll have an issue with that. And, of course, some people even like it

 

What my be more of an issue is the rather low speed of these lenses. At f/8 or f/11 you'll probably be needing a firm rest or tripod to get a sharp UV-photo (in VIS or IR that oughtn't be a problem, though), and forget about fast focussing.

[Avalon]

There is for sale 500mm mirror lens however it's too long focal length for me and they don't have OS, my A7s has no IBIS and it's shaky even with tripod. But I will consider it in future when I upgrade, I like that it's more compact and lighter design :)

[Andy Perrin]

Avalon the biggest list of UV capable lenses is our own sticky! 

PLEASE look at the sticky if you have not seen it. In fact, all people new to this forum should make sure to read the stickies — Andrea has worked so hard to concentrate all the best information in one place.

 

[nfoto]

Some mirror lenses do acceptable for UV flowers and suchlike subjects. Not great, but doable. And of course many can be had for cheap.

 

What isn't immediately obvious is that since mirror lenses tend to be long focal length  in a compact short lightweight build, they are inherently very unstable and must be used on adequate tripods. The best is using a fluid head, which people tend to associate with video and not still photography.

 

 

This UV photo, shot with my old Nikon D70, Baader U filter, and a Russian-made B.I.G. (sic)  500mm f/5.6 demonstrates the expected UV floral pattern. Taken late in the evening so exposure was quite slow at 1 sec or so, howeer the outcome is reasonably sharp.

[Avalon]

Got interested in Soligor 135mm f/1:3.5 Steinheil and München 135mm f/4.5 Cassarit lens. But I'm not sure which is better for UV. Soligor has somewhat poorer UV transmission but maybe it can compensate by wider aperture? Should I stay away from discolored lenses or can they be cleaned?  

[lukaszgryglicki]

This one seems to be OK for me with UV photos - https://www.kenrockwell.com/nikon/200f4Q.htm - but I don't have any device to measure its transmission.

 

[Andy Perrin]

Not entirely sure what you mean by discolored lenses. Some lenses go yellowish because of radioactive elements inside, but those tend to also block UV and therefore aren’t good candidates for our sort of work (although they can be fine for IR). 

[lukaszgryglicki]

I confirm that Atom Nikkor (thorium glass) Nikkor 35/1.4 AI is not a good performer in UV.

 

[Avalon]

42 minutes ago, Andy Perrin said:

Not entirely sure what you mean by discolored lenses. Some lenses go yellowish because of radioactive elements inside, but those tend to also block UV and therefore aren’t good candidates for our sort of work (although they can be fine for IR). 

This new to me, so vintage lens loose UV capability over time? I seen Jupiter 8 lens going yellow but it was due to optical cement. Is that a case with Soligor 135mm f/1:3.5 Steinheil and München 135mm f/4.5 Cassarit lens too? I will ask seller to upload some photos, provided hes doesn't show front view of lens against light.

 

 

 

[lukaszgryglicki]

Yellowing is due to radioactivity of thorium glass - thorium element present there is not stable and it gradually transitions to a long list of its daughter isotopes. 

[Andy Perrin]

Avalon, no, not ALL vintage lenses discolor, only ones with radioactive elements within their glass (like thorium, although that is not the only culprit, Lukas) get yellow over time. If all of them did, we would not have any lenses that worked for UV. I doubt the Soligor, Cassarit, etc. you mentioned have these issues. 
 

Here is a non-exhaustive list of known radioactive lenses:

https://camerapedia.fandom.com/wiki/Radioactive_lenses

[Avalon]

Soligor is faster than Cassarit but transmits less UV that means more visible spectrum will introduced? Both seem to have good image quality especialy when stoping down so I'm not sure which is better for UV imaging. Oh, and are there these lens twins I should be aware?

 

 

[nfoto]

22 hours ago, lukaszgryglicki said:

I confirm that Atom Nikkor (thorium glass) Nikkor 35/1.4 AI is not a good performer in UV.

 

 

 

The same goes for the non-Thorium version  .....

[Andy Perrin]

Cassarit is the better choice there, I would say. You are probably going to stop down for most pictures anyway (at least that’s what I usually end up doing). But honestly you would probably find in practice that it’s not a huge difference between them.