[alt-photo] NuArc 26-1KS problem (Slow printing times) / Cross-post, original @ apug.org

[Loris Medici]

Hi all,

I purchased a brand new NuArc 26-1KS plate burner a couple of months ago,
for the purpose printing with UV sensitive alternative processes.

I've just had time to use/test it and I think there's something seriously
wrong with the device; I currently struggle with pop palladium (Li2PdCl4 +
AFO or Na2PdCl4 + AFO, noble metal solutions' concentration 0.52M, AFO
concentration 1.05M), and the exposure times are incredibly long. (Workplace
conditions, 26C/77F 50% RH.)

I was using a bank of UVBL tubes before (Philips 40W, /05 series - not
manufactured anymore, replaced with /10 series recently), and my standard
exposure time (with a 31-step tablet) was 6:30, giving me 28 distinct steps
including dmax and paper white.

With the NuArc, I print for 900 units (17:15), and the step tablet test says
I still have to give 1 stop more exposure for being able to get 28 distinct
steps, and more importantly I'm currently getting a pretty anemic result
with low dmax. Awful. Something's wrong, WRONG!

What is your usual pt/pd (or any other print out iron process) printing time
(not units, time!) with this unit? (Or, similar units?)

What could cause the problem? I'm suspecting the bulb (NP-80) but it's a
brand new unit and I just don't get how could a brand new bulb work that
much slow? (The visible light illumination is pretty strong BTW.)

TIA,
Loris.