The light bulb can change your gamma.


Here’s an interesting thing. We recently switched to a different exposing booth (much larger for full large-format pt/pd printing) and the bulb is very different. It’s much better for Pt/Pd for sure!

It pulled the over-all printed gamma way down after accounting for min-time max-density. Very interesting indeed. The spectrum of your light can determine the gamma of your print quick dramatically. This is a screenshot showing linear and printed (green line) values. We do 256 step linearization in-house.



What is your light source? Mercury vapor or metal halide plate burner? If so what manufacturer, and more specifically what bulb? Curious because I have spectral output plots for a bunch, mostly Olec and some NuArc I think. They can still be found online I think. Definitely an interesting topic. I have an Olec AL13 though it’s in storage now due to space and noise considerations until I have a separate workspace. For now I use a bank of BL fluorescent tubes that sits below my worktable.


This is just some old bulb that is in the bottom of the machine. The model # is all worn off. No idea what it is. :slight_smile:


What is the machine. I might be able to narrow down what the bulb could be. I seem to remember seeing a picture of you guys moving a big plateburner into the studio a while back, but I don’t remember what it was. Maybe a flip-top NuArc?

PS - Things are going well with the K7-Carbon inks and PiezoDN. I’ll report soon - hopefully next week. And send samples too.