Black Lights (Ultra Violet)

Like Wert, I also use an LS-4 UV light. For anyone who is wondering, the "sliding wavelength selector" is the heavily outline section on the right end of the base which you slide to cover one or other of the filter windows.

Wert, I notice that this is not on your unit as pictured. Do you normally use it?

My light is currently out of service. After 30 or more years, the adhesive holding the filters in place gave way and, as yet, I haven't figured out what filter is which - but I have used the unit without the filters where any reaction is obvious.

For Australian stamps, I also use a Kodak Wratton filter of a relatively precise filter as recommended in the Australian Commonwealth Specialist Catalogue.

Well, taking a look at your guys equipment, seems to me I had better go out and get a better quality UV lite, didn't realize that there were better quality lites, I thought UV is UV but, obviously not, thanks. I'll see what happens when I get that better quality lite.

YES

Robert

I also use the 11W unit from ultraviolet-tools. It is big and used like 3 D-cell batteries. It till work at 12 inches or more compared to most 4W lamps that work at 2 to 3 inches.

I am trying to remember about exceptions but most phosphors are luminescent and then have the after glow to make them phosphors. On some stamps GB stamps, it tends to get washed out and appears more like a stain. Afterglow is very weak on early GB.

A note on stand vs. hand held. I have my UV light set in a light box so that I have my hands free to measure thetag bar width and the distance between adjacent tag bars.