Apologies for the cross-posting (here and D100/D2 forum); but since most of the pictures were taken with the D70, I thought it may be useful to some if I post it here as well...
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UV photography is not a big secret, in fact, there's a fair amount of information out there on the net... but be warned, some of them don't have very accurate information. The most useful sources I've found are Bjorn's site (
http://www.naturfotograf.com/UV_IR_rev00.html#top_page
), some posts on Photo.net and one from my backyard (
http://msp.rmit.edu.au/Article_01/index.html
).
In noting the availability of these information, I will not reinvent the wheel but perhaps chip-in a bit on what I've been playing with (and in brackets - what I paid for).
To begin with, the UV-Nikkor 105/4.5 will come to mind (in the Nikon camp) whenever UV-photography is mentioned. Withstanding the high price (don't ask) and difficulties in locating one, I have to concur that this lens is "the" lens for F-mount UV-photography. Two things are desirable in this lens, the amount of UV transmission and the degree in which it is corrected in that spectrum.
But as we all know, this lens is not for everyone... But as Bjorn and Vivek found out, all is not lost... It is not a big secret that some affordable lenses are well suited for long-range UV work. Nikon E-series 28/2.8 and 35/2.5 are two that were mentioned in Bjorn's site; but they need to have their coatings removed and not many know how to do that safely (including me!!! I have both siting here and not knowing where to begin).
If removing coating is not for you, then the EL-Nikkors are for you, notably, the EL-Nikkor 63/3.5 ($25). It is well corrected to 350nm (most are corrected to 380nm); while a shift in focus may still occurs, it is not as bad...
Fax lens are also well suited for this purpose. Bjorn tried the FAX-Nikkor 160/5.6 with success; I've tried the FAX-Nikkor 210/5.6 with success...
At this point, you might say, these enlarger or fax lenses are not easy to locate as well!!! True, but if you have patience, you'll be rewarded. Withstanding that, other alternatives again exists
Noted by both Bjorn and Vivek, the JML 50/3.5 ($12) is a bargain lens for UV-photograhpy. The only downside is that I can't get it to focus to infinity without some serious modification; but for close-up work, it is very good ...
What about fax lens? I've also tried with Fujinon-Xerox 24cm/4.5 ($8) and it will pass a fair amount of UV. Again, there's a down side... focus shift. But if you're patient, you can't go wrong with a $8 UV-tele
But let's take this one step further.... Why not try other lenses that are not frequently mentioned? Well, why not
First up, the Nikkor high-speed lenses are surprisingly quite usable at large apertures (withstanding the focus-shift). The CRT-Nikkor 55/1.2 for example can be used to provide some useful images... usable even when stopping to f4 (optimum).
Anything closer, the REPRO-Nikkor 85/1.0 can be called for service (despite its beautiful multi-coating) ...
Unfortunately, anything further is rather difficult. At 5x using a MACRO-Nikkor 65/4.5 (which passes very little UV), you need insane amount of light. In this shot, my flash almost hit the subject and yet, there's not enough light. I did sprinkle a little water to "brighten" up the pic"... but no go. It does make a nice simulated "moonlit" shot though
Other high-speed lens I have did not perform so well. That being said, it can be done. What's more, they give a more interesting view to UV-close up when compared to the many I've seen so far ... XR-Heligon 75/1.1 ($12-50) passes little ...
... while TV-Heligon 42/0.75 ($6) is a little better ... Both suffered from focus-shift though.
Filters
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Now, what about filters and filters combination? Bjorn has done most of the leg work so I'll just let the pictures speak for themselves. Out of the various combinations, my vote goes to the Schott UG-1 + BG38 as well.
1) The FF filter that come with UV-Nikkor 105/4.5 (free ... sort of) ...
2) Similar to FF, the Hoya U-330 (free ... sort of. Edmunds Optical - 2x2 $100++) ...
3) Fave of the lot, the Schott UG-1, available as B+W 403 (52mm $30++) ...
4) The least use U-340 (Edmunds Optical - 2x2 $100++) ... because it needs more light!!! ...
To sum things up thus far, all this has been very interesting for me. And I hope this report can bring some interest to some (that don't visit those sites that I mentioned
PS: All shots were taken with my el-cheapo-easily-modified Vivitar flash ($40++)... All in all, UV photography can be done fairly cheaply (and that's no big secret
