Damn, what's causing these holes in my emulsion!?!?
I've been getting these for a bit and it's such a pain to have to block them or tape them up. They're bigger than pinholes, sometimes they're there, sometimes they're not. The holes are not on the dried emulsion, they only show up after washout. If anyone has an idea, I'd love to hear it. Here are things I do that do NOT help:
-Make sure emulsion hasn't gone bad
-Let emulsion warm to room temp before coating
-Multiple coats of emulsion
-Make sure emulsion isn't full of air bubbles
-Get a good exposure
-and more stuff
Those look like water marks. If you are storing your screens near a water source sometimes they get splashed with water and those dots form. This happened with out power washer but it was more misty. Also if your screen are wet before coating this happens. They need to be 200% dry. Also are you storing your screens in a room that has air movement? Humidity can play a factor. Look at your screen before you expose it to see if you can make out any dots. Make sure your glass is clean. Make sure that you goop scoop has no water in it. Also what type of film are you using for your exposure. Sometimes vellum can have tiny dark parts on the film. I would inspect the film the screens that it happens on. Also do a retest with the film but most likely this is not it. Does it happen on the same screen? If so get the screen re-stretched. Hope this is helpful. Its the little things that make all the difference.
Yes! I think that's it! I dry my screens outside after reclaiming and sometimes I'll catch them just as it's starting to rain. We've had a particularly rainy summer in Atlanta, so that's probably why this is happening more frequently. That would also explain why the holes are usually ovals, since the screens are typically drying vertically. Thanks Underpressure!
It was totally rain drops causing the problem. Maybe it's just dirty city rain, but if you dry screens outside and it starts to sprinkle as you're bringing them, wash them again before putting on emulsion. That shit was driving me crazy. I reclaimed all those screens and did everything the same as I've always done and the holes were gone.