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David Nash
12-Nov-1998, 09:50
I am starting out in Platinum printing, and am building up the equipment and che micals I will need.

One of the things I'm having trouble finding is a UV lightsource.

I've seen that Aristo make a platinum printer, but I already have a contact fram e, and only need the light. I've seen a plan for making my own, that uses 2ft B lack flourescent (not sure about the spelling) tubes, but I haven't really got t he time (or the ability) to build it myself.

I believe you can get a mercury black light which has an eddison screw fitting, but I'm not sure if it would give even coverage. I will be printing 5x4" initia lly, going up to 10x8". I won't be going larger than that until I've had consid erable experience on these smaller formats. Has anyone used this type of lamp, and if so, is it as good as the strip lights?

My other problem is that I live in the UK, and I haven't been able to locate any supplier over here.

Any advice will be greatfully received.

Sergio Ortega
12-Nov-1998, 11:14
David, The best UV light source is the sun. Many platinum printers still use i t exclusively. It's all you really need. Cheap and plentiful here in Florida; might be a problem in UK.

For starting out--indoors--the commercial platinum printing units can be very ex pensive. Depending on the size of the print, three or four inexpensive, fluores cent light units, with UV bulbs replacing the standard "white" fluorescent tubes , placed side-by-side and suspended a few inches above your contact print frame, will do fine for platinum printing.

Try to space the light tubes close enough so that you have no more than an inch or two between the tubes. To achieve spacing this close, you may have to remove the fluorescent units' reflectors, if so equipped. This creates a more even li ght source, and prevents the parallel, alternating light/dark striations you can get on the print when the tubes are spaced too far apart, or suspended too clos e to the contact print frame surface. On the other hand, if you suspend the UV light source too far above the print surface, the exposure times will be rather long.

With platinum materials, you can work indoors with just a plain, low-wattage, ye llow incandescent light bulb as a "safelight". Also, it's not a good idea to l ook directly at the UV lightsource during the long exposure times...it can damag e your eyes.

Hope this helps. Sergio.

Tony Brent
12-Nov-1998, 23:41
There are several small plateburners used by print shops that may show up at auc tions or other printing equipment sources.

Just as an idea. I wonder if you could adapt the UV tubes from an EPROM eraser? They are available from electronics suppliers, swap meets etc. I have no idea ho w strong they are, but it might be an alternative.

Aristo's contact burner would work fine but as I remember it isnt cheap. Like th e other fellow said, the sun is an excellent choice and its free, but it isnt al ways available.

Bob Salomon
16-Nov-1998, 20:10
Kaiser introduced UV A copy lights for their copy stands which could possibly be used. The set consists of two reflectors each equipped with 3 18W UV A fluorescent tubes.

It is a limited production item intended primarily for scientific work on a copy stand and is not inexpensi

Sean Billy Bob Boy yates
16-Nov-1998, 20:49
FWIW George Tice used to use a UV Sunlamp, which when it was made in the 70's, you could use three feet from the print, but you had to keep it on the entire time to prevent it from changing it's output. These can be found at yard sales from time to time, I've beeen stockpiling them against the day I start in Plat/pall, but they are no longer made. In any event keep heat in mind when you're printing indoors and be aware of any potential fire problems from heat build up or inadequate wiring.