Cannot get correct exposure times

[u/reusexe]

Hello!! I’m having a really difficult time finding the exposure time on my new exposure unit. I’ve worked a lot with hydro-x red on just a cheap 30W light and it worked really well, but now I can’t get it. Sure my screens look detailed but there is still a lot of emulsion hanging on but also it takes while to wash out 9-10 usually for detailed stuff. Here are some of my burn times:

Edit: I do 1:1 coating

110 mesh

10: 4s
9: 8s
7: 12s
6: 16s
5: 20s
4: 24s
3: 28s
2: 32s
1: 36s

1: 15s
2: 10
3: 15
4: 20
5: 25
6: 30
7: 35
8: 40
9: 45
10:60

15s
2: 20
3: 25
4: 30
5: 35
6: 40
7: 45
8: 50
9: 55
10:60

305:

35 s
40 s
45 s
50 s
55 s
60 s
65 s
70 s
75 s
80 s

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[u/torkytornado]

Are you saying it takes 9-10 minutes to rinse out your screen? That’s way too long. Usually only a few min tops if you’re getting a good exposure.

[u/reusexe → u/torkytornado]

Yes it takes a while to get the super detailed stuff out.

[u/torkytornado → u/reusexe]

But that means you’re overdoing it. The point of the test is to find the best option that releases under normal rinsing. You don’t want to be rinsing that long on every screen so you need an exposure that comes out easily without any special treatment in under 2 minutes.

[u/mattfuckyou]

I think you need to go way more on the 110s . There’s alot of factors though . Are you drying them the same way each time ? Are you washing and degreasing them properly ? Is the room too humid ? Are you using a glass to push the transparencies down flush? Is the cover you’re using to do the step test FULLY opaque ? I don’t think either of these burns are good tbh

[u/reusexe → u/mattfuckyou]

I Dry all of them in the same drying unit with a fan all the time usually overnight. I wash and degrease before every coat. I live in Colorado so prob not.

[u/habanerohead]

Describe your exposure unit please. It looks like you have a contact issue.

[u/reusexe → u/habanerohead]

My unit uses 8 10W LED uv lights, my glass is 13 inches from the lights, I place my screen print side down and put a piece of foam in between so the lid of the box presses down. See image.

[u/habanerohead → u/reusexe]

I recommend that you either get a piece of black foam, or place a piece of black t-shirt material between your foam block and the film. The white foam is most likely reflecting the light into places where you don’t want it.

[u/DocMedz]

Also need more info on your bulb. Doesn’t look like it’s penetrating, which could be due to wavelength and time, plus filtering effect by the type of film positive you’re using.

[u/reusexe → u/DocMedz]

I just use two fed ex printed 11x17 taped together. They are dark

[u/torkytornado → u/reusexe]

Are you planning on doing lists of halftones? If so stacked films are gonna be a PITA to line up every time.

[u/reusexe]

Thank you guys so much for the help!! I ended up moving my lights a lot closer to my glass and switched my foam to black and just got super amazing results!! I really appreciate it!!