# Halftone printing priblem



## Flipr (Sep 1, 2016)

Hi printers. 
I was wondering if anyone here could find a solution to my halftone printing problem. 
I tried to print a halftone image using photoshop, Canon ip8700 printer, on 305 mesh with a frequency of (both 55 and 61) and an angle of 22.5. I've tried exposing the image using ASC360 exposure unit (usually works very well for me) and a 500w work lamp. I even went as far as using a exposure calculator.
Problem is, when I wash out the screen, I can see the image but it doesn't seem to wash everything out or the print isn't getting the "shadows or deprh) it's not printing the ink (white plastisol on black shirt).
Any help would be appreciated and needed.

Thank you


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## 2020 PrintWorks (Apr 22, 2011)

Do you have a pic of the test print. Sounds like its overexposed. Could be undercutting causing you to lose the smaller dots or could be your film isn't dark enough. Does your unit have a vacuum lid?


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## krikster (Aug 8, 2013)

Yea halftone dots with a work lamp is sketchy anyway. You have to expose it too long. If you are insisting on that method or really can't afford a small exposure unit with tubes then get a fast emulsion so you can really dial back the time of exposure. Like the previous post said. It could mean your positives are not getting dark enough either.


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## Flipr (Sep 1, 2016)

Thanks for the replies.
I usually use a small exposure unit. My exposure calculator said 30sec is my time. 
I thought about the over ecposure, but when I tried other times (20-25) most of the image was washing out. (I'll post a picture of it later tonight).
My exposure unit doesn't have a vacuum. Just 2 locking clips. I did think about it not being dark enough (film) but I don't have a rip program. I am however looking at purchasing one. A little expensive for a hobby


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## 2020 PrintWorks (Apr 22, 2011)

30 seconds is impressive for a work lamp.


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## Flipr (Sep 1, 2016)

Lol. No. 30sec with exposure unit. It was taking almost 20min for the lamp


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## ole Jobe (Jun 16, 2009)

Have you tried printing 2 films and layering them for more opaqueness (sp)? I use a 500 watt work light, 20" from screen, 8 min., most mesh. No problem


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## Flipr (Sep 1, 2016)

Layering 2 films would be good as a quick fix but would get a little more expensive than paying for a rip software. I'm just not sure what's good for my Canon printer.


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## jbjet45 (Apr 22, 2013)

when i first started with halftones I had the best luck rinsing a little at a time. By that I mean I would spray the screen both sides with luke warm warm water then let it sit a minute or so then spray it again then let it sit and so on until it starts to dissolve. sometimes I would lightly rub both sides with my hand when it was necessary. Now that I have a nice vacuum unit I can usually hit it with a power washer with good luck.


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## Flipr (Sep 1, 2016)

Thank you. I'll try the letting it sit for a while. I'm also trying to print image with suggested "true black" setting in photoshop. Films look darker than my previous films


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## hawaiianphatboy (Apr 28, 2008)

Flipr said:


> Thanks for the replies.
> I usually use a small exposure unit. My exposure calculator said 30sec is my time.
> I thought about the over ecposure, but when I tried other times (20-25) most of the image was washing out. (I'll post a picture of it later tonight).
> My exposure unit doesn't have a vacuum. Just 2 locking clips. I did think about it not being dark enough (film) but I don't have a rip program. I am however looking at purchasing one. A little expensive for a hobby


I don't have a vacuum lid on my exposure unit either. after placing the screen down, I place a black towel over it, then a piece of foam the size of the screen inside of the ink side of the screen before closing and securing the lid. That has done wonders for me when dealing with halftones. Also on the rare occasions that I break the glass of my exposure unit, I put the screen on a cart with the towel underneath it, the print side up and the positive on top of that. After securing the positive I place a piece of glass over the positive and then cover it with a black towel. I roll the cart into the sunlight, remove the towel for about 30 seconds then cover it back up and take it indoors where I wet the entire screen, then wash it out. This has also worked great during those times that my exposure unit was unavailable to me. Good luck and Aloha


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