Wednesday, April 15, 2009

Cheap UV flashlight for reflected UV photography?

Cheap UV LED Flashlights from China flood the market now, so the question was, if tehse would be suitable to do reflected UV photgraphy. Therealöly cheap ones have 390/395nm UV LEDs built in - these won't work anyway since the used Baader U-filter cuts off at 390/395nm. But there are others, namely the 380/385nm versions and the more expensive 370nm versions which seem to be suitable.

A quick test now comparing the results with that of my UV enhanced High Power Xenon flash when doing reflected UV photography.

Equipment used was:  Nikon D70 (unmodified), Baader U-filter, X35 lens. Exposure: f8 and 2sec for the UV flashlight, 1/160sec for the UV flash at ISO400.

[click on image to get a larger one]

UV LED - That LED is NOT the Nichia UV LED I usually use, so don't get confused:

UV Xenon High Power Flash:

I guess the UV flash investment is well worth it, since it reveals much more fine details, stimulates all RGB channels of the camera chip and seems to also go much deeper into UV (a prior result showed response down to 320nm). But I have to be fair, for a simple setup or a beginner on a tight budget  it might well be worth trying and move on later.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site