First time poster here though I have scoured these forums for useful info that has helped me immensely so first off thanks to all of you.
I have found some very interesting threads here on solar exposure and would like to try it on my roof. I will be exposing a small screen with a chromaline exposure calculator tomorrow around high noon to get an idea of exposure times for autotype 8k plus on 305 mesh. If this proves to be an efficient way for me to expose screens I will want to really dial in the exposure with a light integrator.
Does anyone have a suggestion on where to find a reasonably priced integrator? Or have tips or suggestions on solar exposure? Any advice would be greatly appreciated.
We've exposed screens using solar and autotype 8k plus. I would just check ebay and the M&R classifieds for a used integrator. They aren't that hard to come by but having one would be great with a solar setup as our Brooklyn sunlight changes so drastically. You can also make a pretty portable vacuum exposure using space bags and a shop vac
I bought a nice little handheld unit from Chromaline a few years ago, but they stopped selling them.
You want the medium speed dual cure (autotype 8k, Murikami pro are similar) as any one pot stuff is too fast/sensitive.
Here we are running aorunf 80 seconds on yellow mesh/45 sec white in summer full sun, I would imagine you will need to go longer now where you are.
I always figured if you could get a baseline exposure with a good time and knew what the UV index or some type of reading like that was, you might be able to make a sliding scale and just check the UV index for the day in your area.
when we were in deep winter here and the sun barely comes up, it could take an hour or more, especially if it was overcast. but if you could see a shadow, there was enough. We had a vacuum frame and integrator, so that helped tons.
Thanks for the suggestions. I will keep my eyes peeled on ebay and M&R but most of the integrators I have found look like they have come off of large exposure units and seem to be missing the photocell. A handheld unit would certainly be ideal, too bad chromaline no longer sells one. Andymac do you remember around what your integrator cost you?
I guess the other option is to just expose a small screen with an exposure calculator to get an idea of exposure times each time I expose screens considering the light intensity will probably be changing daily this time of year. I exposed a few small screens yesterday in full sun using autotype 8k with a uv index of 4.1 and 40 seconds was right on. I was really surprised by the detail I was able to get from the stencil too. It will be a bit of a pain hefting larger screens up and down the stairs but it will definitely be worth not having to spend 10k+ on a single point light system that uses electricity, if I can manage to get consistent results.
Do you think the space bag will hold better contact than a spray tack? I guess it would probably be cleaner.
Anyway thanks again for your thoughts, much appreciated.