Jump to content
UltravioletPhotography

Xenon flashes for UV


Andy Perrin

Recommended Posts

At least they used BG38, which isn’t the best filter for that purpose but blocks IR reasonably well. I have seen “UV” photos made with U-glass only that thus were actually IR with a touch of UV.
Link to comment

The filter thickness is very important.

I don't see any filter thicknesses noted in that paper. I see the term "2X" used preceding BG38, for example, but 2X of what thickness?

Let's say that they are using some BG38 2.5mm thick, then 2X of that would be 5mm thick, enough to cut at OD3 at 700nm, and then stacked with KV418 would provide a good functional visual range filter.

I typically use BG38 alone just 2mm on my camera for visual, but technically it contains UV, but doesn't show given the visual range overpowers the UV. It looks natural on my camera.

Yes, for visual range / IR suppression both BG39 or S8612 would work well for that at less thickness than BG38. Even BG40 would work slightly better than BG38, but BG40 needs more thickness also.

I would like to know what thicknesses they are using, that info should be included.

 

DUG11 (several versions) is a coated version of UG11, similar to the Baader U in design, but it has a higher IR leak, it is expensive and hard to get, and would still need suppression for the higher IR,

which would also cut the lower UV, so it has never looked useful to me. You would be better off with a Baader U, or some U+BG stack.

Link to comment

I may have over thought that, because I would use BG38 2mm + KV418 for UVIVF, some would use BG40 2mm or Baader UV/IR-Cut,

whatever you use for usual visual, just add KV-418 or Zeiss T* to it and you got a nice visual fluorescence filter for the front of any stock or full spectrum camera.

You can also add a GG4## filter behind the T* or KV-418 to further attenuate the cut off point of the visual violet, some like to cut at 435nm (GG435) for example.

S8612 and BG39 cut off more 600nm range of course, but those are not what I use for natural visual conversion, however a few people with some cameras do use those and find them most natural for their camera.

But for me, with my Nikon, BG38 looks best actually.

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...