# AccuRIP Droplet Weight Suggestion for Halftones



## Tacoma (Jan 31, 2016)

Hey everyone,

I was hoping someone could give me some advice with AccuRIP. I am trying to print a halftone image using a screen mesh of 305. My question is does anyone have a recommended droplet weight in AccuRIP? 

At first, I tried to print on a 156 and 200 mesh with a film positive of 1440 x720 and a droplet weight of 12. After exposing the screen the first couple of prints were okay but the ink started to bleed through areas that made the image distorted. The ink that I am using is black plastisol and white plastisol for another screen. 

Any help would be most appreciated! 

Thank you!!


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## Twisted Grafix (Oct 5, 2016)

Have you done the droplet weight test print in Accurip yet? If not, you should start there. The test will print out different droplets with a density strip and solid box. The proper weight is the one that is dense, but not puddling/running/dripping. Printers are all different, so the test is extremely useful. My settings won't work for your setup because I use the advanced curve settings for my output on my printer. Frequency will also come into play for the dot size.

It also sounds like you may have a couple other issues going on because ink bleeding is not normally caused by the density of the print film. 

Is your off contact set correctly for your screens? Are your screens tensioned properly or are they old? Are you printing a spot color, simulated process, or CMYK print? Are you over flooding the screen? Are you squeegees sharp? A little more info about what you are using and a pic or two of the bad print would really help.


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## NoXid (Apr 4, 2011)

As Twisted noted, don't think your issue is droplet weight.

With a halftone, you should do a few junk/scrap prints to get the screen inked up, as the first print or two will be light compared to the rest. You might need to adjust your halftone for Dot Gain ... which is the hard part of getting a halftone dialed in, and/or adjust your squeegee technique.


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## Tacoma (Jan 31, 2016)

Twisted Grafix said:


> Have you done the droplet weight test print in Accurip yet? If not, you should start there. The test will print out different droplets with a density strip and solid box. The proper weight is the one that is dense, but not puddling/running/dripping. Printers are all different, so the test is extremely useful. My settings won't work for your setup because I use the advanced curve settings for my output on my printer. Frequency will also come into play for the dot size.
> 
> It also sounds like you may have a couple other issues going on because ink bleeding is not normally caused by the density of the print film.
> 
> Is your off contact set correctly for your screens? Are your screens tensioned properly or are they old? Are you printing a spot color, simulated process, or CMYK print? Are you over flooding the screen? Are you squeegees sharp? A little more info about what you are using and a pic or two of the bad print would really help.


Thank you for your reply! My off contact is set to about 1/8th. I've used all 8 screens that I have, some used and some new but they all gave the same results. The ai. file is set up as CMYK but the linked file is set up as a spot color from PS. I flood the screens once before pressing and my squeegees are pretty new and sharp. 

The image that I'm trying to print a little low in quality. Could that possibly be the issue? I tried to fix it up in PS as best as I could but the results remain the same. How high should my off contact be? I'm printing on cotton t-shirts.

For some reason, this thread is not allowing me to post pictures... But here are two links that you can view them on:

Black Ink Print:
https://opticdesignsolutions.com/wp-content/uploads/2018/08/Issue1.jpg

White Ink Print: 
https://opticdesignsolutions.com/wp-content/uploads/2018/08/Issue2.jpg


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## Tacoma (Jan 31, 2016)

Thank you for your response! I've done over a dozen test runs when printing and they got worse as I went on. I've also tried different squeegee techniques as well. As for the dot gain control, I feel that is a little too advanced for me... I don't want to mess anything else up.


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## Twisted Grafix (Oct 5, 2016)

Your issue is starting with low quality artwork from the get go. When screen printing a halftone image, you will lose dpi, so you need to start with high quality, crisp images so that when they print they look great. Low quality will suffer every time.

Also, the shadows and highlights need to be adjusted. That's a different issue, but it will also cause a loss in detail on the print.

"As for the dot gain control, I feel that is a little too advanced for me... I don't want to mess anything else up."

You'll need a transmission densitometer to adjust this properly....Fix what you can now, then worry about the advanced stuff later when you really need it to be spot on...


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## BraaaaapGraphics (Jul 6, 2015)

If you were to convert this image to a grayscale you would get muddy results, taking the grayscale to press would give you muddier results and become a mess. 

In order to print a clean and accurate gray image convert this color image to LAB mode in Photo Paint or Photoshop then extract the Lightness channel that handles only "contrast data". This is the cleanest grayscale you can ever make. 

You would then copy and paste the Lightness channel only to a new page and make your final adjustments. 

You would then print through Corel as you would normally or how ever you print accurip will handle everything 

I use this for black on light garments and you only get one push or pull of the squeegee or it will be to dark in spots hope this helps


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