Black Light Bulbs

[ced]

Excuse if already posted. Would these bulbs be good for Gum Printing as they are for Cyanotypes please?
(http://www.velleman.eu/products/view/?id=381476)
They are already installed at home and make excellent Cyano's but I want to make Gum's too.

 

[Uncle Goose]

If they do Cyano's then they will do gum's too.

 

[ced]

U.G. Thanks for responding and what do you think the difference in exposure time if you have experience with this method?

 

[Loris Medici]

Ced, that highly depends on the pigment / dichromate / gum content and coating thickness of your emulsion. For my usual working procedures, gum was around 2 stops faster than trad. cyanotype. But this is absolutely non applicable to your working conditions / style. You'll have to test it for yourself.

Regards,
Loris.

 

[ced]

L.M. Thanks for this info it might just be a pointer!

 

[AgX]

Excuse if already posted. Would these bulbs be good ...

These are no "bulbs". But they are fluorescent tubes, which basically only emit UV light.
(That in household tubes is transferred by the inner coating into visible light.)

In contrast the classic "black-light bulb" is an (maybe overrated) incandescant household lamp with an filtering coating that only transmits the UV/far-blue part of its edmission, wich is very weak though.

 

[ced]

Duh...

 

[AgX]

I never came across the lamp you linked to, but often the "black" incandescent ones. So when reading black.light bulbs I immediately think of these incandescant ones.