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halftone measurment results. WOW, dot gain galore!

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blue moon:
So I printed some films today and measured the dots on the film. To no surprise, the FIlmMaker shined again and white it was off, it was in 2%-4% range. Much better than the two other RIPs I used previously.

Next step, I burned my crappiest 305, set the squeegee to 4 (on a 10 scale) and floodbar on 2 (again 10 scale). 70 duro (single) blade.

Printed the test pattern and Holly Batman! to dot gain is crazy!!!
 5% reads 17%
10% reads 27%
50% reads 72%
75% reads 83%
and 95% actually reads 95%.

looking at the curves in the RIP they actually adjusted the top end so I am not surprised that it is right on in the uppers, but 20% out in the middle?
Now this is not the issue with a RIP as it obviously created good films.

So I can go into the settings and set up an adjustment curve, but am worried that I might no be laying down enough ink if I do that. As it is, my old RIP used to print the 50% dot at 64%, so that means it was an 85% or so before. If I go and tweak it down to 50% I will be removing 40% of the ink being laid down. That scares me! There is not going to be much left on the shirt at that point . . .

Does anybody have any experience with this? Am I crazy for even worrying about it? or am I crazy for even asking and should go and remap that curve?

pierre

squeezee:
If you want to print 50%, move the curve so that you get 50%
You might find that the shirt looks flat compared to the usual because we are used to colours getting 'popped'.  If you looked at a cookery book with realistic colours it wouldn't appeal so they saturate the colours.
I don't understand the rest of the post? Filmmaker films were within 2-4% of their target?  That gave dot gain on your press?
You just need to set up your RIPs properly.

Orion:
Pierre, if you printed a 50% dot that gained to a 72%, that is not a 20% gain it is 44% gain. Yep, you need to go back in the rip and adjust the curves. I don't understand the amount of dot gain that you are experiencing in the lower percentages, the numbers aren't making sense to me. How hard are you flooding your screen?

blue moon:

--- Quote from: squeezee on April 20, 2011, 06:36:25 AM ---If you want to print 50%, move the curve so that you get 50%
You might find that the shirt looks flat compared to the usual because we are used to colours getting 'popped'.  If you looked at a cookery book with realistic colours it wouldn't appeal so they saturate the colours.
I don't understand the rest of the post? Filmmaker films were within 2-4% of their target?  That gave dot gain on your press?
You just need to set up your RIPs properly.

--- End quote ---

Dave,
nothing wrong with the RIP all the gain is press related!

Yes, I was worried that if everything is adjusted, prints would not look as good (less color and less coverage) as they do now.
I just might have to create another profile and test it . . .

pierre

blue moon:

--- Quote from: Orion on April 20, 2011, 10:35:32 AM ---Pierre, if you printed a 50% dot that gained to a 72%, that is not a 20% gain it is 44% gain. Yep, you need to go back in the rip and adjust the curves. I don't understand the amount of dot gain that you are experiencing in the lower percentages, the numbers aren't making sense to me. How hard are you flooding your screen?

--- End quote ---

I am flooding pretty hard, and certainly can adjust it both on the press and in the RIP.

re: lower percentages. So when I print the film and it is supposed to be 5%, it might be a few points off. So lets say, the 5% dot prints as an 8% and then at the press it gains to 17%. That's 200% more coverage!!!

Trying to read the dots on a shirt is not quite exact science, there was a lot of fluctuation. I was just surprised to see how much dot gain there is!

pierre

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