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UltravioletPhotography

UV capable flash


Gridluck

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I've read some articles here and there regarding uv lighting gear (flashes, torches, etc) and got self a list of current "best" affordable flashes for uv photography

- quantum t5dr+qf80(1st) and

- canon 199a (2nd);

 

When looked further into package contents of each, I found that no additional filters are included to make them readily useful upon purchase. It is said that the quantum flash is preferred over modded 199a for its relatively higher power of output (150w). I looked into specs, but found no details about the estimated output of uv or a graph with nm range, neither could I find any for 199a.

 

The t5dr seems like a regular flash with exposed bulb, which becomes "uv capable" when one installs a uv pass filter to a qf80(basically a filter holder). To me this seems no different than a setup where a filter is on a right lens, since the bare camera sensor shall receive a filtered uv content either way. If this is true; then please explain why the whole need of qf80, if it's just their trick to get more clientele, then why no other uncoated flash tube and kit manufacturers emphasize on that (uv capability) as an option? If not, then what's so special about t5dr or 199a that isn't listed in specs?

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These flashes are not sold by their manufacturers as UV-flashes. These flashes are sold as standard flashes for use in typical visible wavelength photography.

 

Any flash like the Canon 199a must be modified in some way in order to become a dedicated, UV-capable flash. This modification typically involves the removal of the existing UV-blocking filter over the flashtube followed by the addition of a replacement UV-pass filter (which may or may not block other visible or IR wavelengths).

 

The flashtubes are Xenon and so any Xenon transmission chart may be consulted for the output wavelengths.

Here is a lot of information about Xenon flash:

https://www.photonics.com/Article.aspx?AID=44487

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Gridluck, all xenon flashes are the same as far as I know. The real question is whether some coating or filter is blocking the UV from getting out. In nearly all cases, the answer will be yes, and you will have to remove it somehow.
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so the only uniting factor for both flashes is that their bulbs are uncoated.. and there seems to be a lot more varieties out there, and at much lower price per watt output, wish they'd add more emphasis on this so to drive the market a bit towards visible invisible..

 

someone really need to create a uv flash database, something like for lens - http://www.macrolenses.de/objektive_sl.php?lang

am sure the list will grow fast,

 

4800 Watts for ~$3500, vs 150W of t5dr for ~$1200+ (kit)

https://www.adorama.com/pp900753.html

+ (uncoated) https://www.adorama.com/pp101552.html

 

or its lil bro

1200W for ~$1200, and much better than 150W of t5dr

https://www.adorama.com/pp900755.html (already uncoated)

 

please correct me if my math is wrong here, but if one was to pick a uv suitable standard or studio flash, in this world where majority is not (yet) interested in uv, would it be safe to assume that any tube stated as uncoated is a go?

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I found that no additional filters are included to make them readily useful upon purchase.

 

Depends on what you mean by "readily useful"

 

For reflected UV with a UV-pass/VIS+NIR-block filtered lens then a flash with full spectrum UV-VIS-NIR output works just fine.

 

If on the other hand you wish it to be "readily useful" for UV induced VIS fluorescence then you need a VIS+NIR blocking filter on the flash.

 

I have a couple of the old Canon 199A and they are quite easy and safer to modify. One of our members is selling a filter stack which fits into the removable wide angle diffuser. One could acquire a second wide angle diffuser to hold a UV blocking filter for normal VIS+NIR output if desired.

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If you really want high UV output then you should go with an uncoated quartz tube that can handle short duration and high current. This pushes the UV & IR emission in favor of the UV output and at a higher level than a "common" pyrex type xenon tube.
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Depends on what you mean by "readily useful"

 

For reflected UV with a UV-pass/VIS+NIR-block filtered lens then a flash with full spectrum UV-VIS-NIR output works just fine.

 

If on the other hand you wish it to be "readily useful" for UV induced VIS fluorescence then you need a VIS+NIR blocking filter on the flash.

 

I have a couple of the old Canon 199A and they are quite easy and safer to modify. One of our members is selling a filter stack which fits into the removable wide angle diffuser. One could acquire a second wide angle diffuser to hold a UV blocking filter for normal VIS+NIR output if desired.

 

ok i've to admit i got a bit confused with placement of [uV-pass/VIS+NIR-block] (baader-u2 in my posession) filter; below must be right

for uv only the [uV-pass/VIS+NIR-block] filter shall go on adequate lens mounted to full spectrum camera - this one is clear as blue sky in visual spectrum

for uv induced vis flourescense (uvivf) - all i need is visual (in pitch black env?), so [uV-pass/VIS+NIR-block] filter will go on flash, and [uV/IR Hot-Mirror] Filter on full spectrum camera

 

for the latter case i need a man-made uv source, so for primary testing i got self a cheapo 199a, still waiting for it to arrive, but for the long term I'd like to invest in a decent flash, preferably dual use (conventional flash photography and uv, call it flashU); so far the t5dr is the only one on horizon, am still thinking it out - going that way means going all the way with all quantum gear, there are a lot of other good competitors, just not clear which one outputs comparable uv

 

overall finding such a jewel flashU is not easy by just googling out, turns out that not everything is listed in specs for normal people, details whether a bulb is coated or not, diffusers material and coating specs, halogen or xenon, uv or not power rating, spectrum coverage, etc are not always there, and this why the need for such list for future uvaholics

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Well, now you have me confused when you said "....for uv only the [uV-pass/VIS+NIR-block] filter shall go on adequate lens mounted to full spectrum camera - this one is clear as blue sky in visual spectrum..."

 

A UV-pass/VIS,NIR-block filter is not visually clear.

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.....not everything is listed in specs for normal people, details whether a bulb is coated or not, diffusers material and coating specs, halogen or xenon, uv or not power rating, spectrum coverage, etc are not always there, and this why the need for such list for future uvaholics

 

I certainly agree in principle. However, that type of detailed information is also not available to us here on UVP. What I could possibly do is put together a list of UV-capable flashes which have been mentioned here on UVP. Perhaps that would be useful?

I will add this to my To Do list. :lol:

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Well, now you have me confused when you said "....for uv only the [uV-pass/VIS+NIR-block] filter shall go on adequate lens mounted to full spectrum camera - this one is clear as blue sky in visual spectrum..."

 

A UV-pass/VIS,NIR-block filter is not visually clear.

 

my bad, it was a very uvaholic expression, normal people would say

 

....for uv only the [uV-pass/VIS+NIR-block] filter shall go on adequate lens mounted to full spectrum camera - this part of process is very clear to me, I understand it well:)

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