UV Strobe

[Annie M.]

Could someone please inform me of the customary use for UV strobe bulbs.

Thanks!

[Matt Miller]

In the HVAC industry UV strobes are used in air handlers to kill bacteria in the air, on coils, in drain pans, etc. I've never heard of strobes being used for photographic printing, but that doesn't mean they're not.

[Annie M.]

These are strobes are used for photographic lighting I was just curious as to the application.

[Mark Sampson]

I believe some flash manufacturers (Balcar?) offer flashtubes with UV filtration built in. This is to reduce excess UV output- which can shift the color of the light too far to the blue. In addition, many fabrics are UV-reflective, and especially in the wedding photography business, strobe lighting could cause strange color casts in the bride's dress that could not be corrected out in the print. I have never seen this problem myself, not using Balcars or shooting fashion or weddings; but it could be an answer to your question...

[Scott Walton]

All major makers have the addition of UV bulbs. The purpose is to reduce the "blue" you will get when shooting chromes. It makes for a cleaner light when temperature has to be absolute. If your shooting negatives, don't even bother with the added expense!

[Donald Miller]

"All major makers have the addition of UV bulbs. The purpose is to reduce the "blue" you will get when shooting chromes. It makes for a cleaner light when temperature has to be absolute. If your shooting negatives, don't even bother with the added expense!"

The addition of UV takes light into and through the blue spectrum because UV lies beyond the blue into the violet range. Near band UV lies beyond 400 nm. Flash tubes are normally filtered to eliminate UV. Why someone would use a UV emitting flash tube for photographic illumination is beyond me because everything photographic tends to be aimed at the reduction and elimination of UV.

[Michael Mutmansky]

Annie,

There are three purposes that I can think of for UV flash tubes. Whether any of these are actual applications for the tube you mention, I do not know.

The first is for use in strobe units intended for dance clubs and similar for special effects strobing. If the strobe is placed behind a Wood's glass filter, all that would come out would be UV light, which could cause some interesting glowing effects when used in low ambient light levels.

Another is in scientific study, where high levels of UV are desired for a specific purpose. Look at these, for what I mean:

http://www.srs.fs.usda.gov/4505/hanula/pollinator_studies/uv_photography.htm

http://www.canfieldsci.com/special/uv.shtml

Finally, there are applications where photography is done using UV light as the specific (and only) light source. Items may fluoresce under UV, and certain films are also sensitive to UV wavelengths. So, you could be taking a visible light picture based on fluorescence of UV sensitive materials, or you could be taking a picture that uses a UV bandpass filter on the lens to only permit UV into the film. Here's a whole bunch of sites that pertain to this:

http://medfmt.8k.com/mf/uv.html

UV is also used in many industrial processes, including UV curing of certain epoxies, and also for flaw inspection of material finishes and a variety of other uses. These are normally done with continuous light sources, though, so I don't see this as an application for a strobe unit.

---Michael

[Annie M.]

Interesting aspects of photography that I had not known..... Thanks everyone.

[Ellis Vener]

Do you mean flash tubes or protective Pyrex™ shells that are coated to suppress UV light or filters to let almost nothing but UV light through?

[Annie M.]

Ellis,

My initial assumption was that there existed flash bulbs that are or were manufactured at one time to have a high output of UV light and I was wondering with what subject matter or circumstances this type of light source was used.