[noiis]

Hey guys! Great to be among you. Have learned a lot!

I'm used to working with images, not with vectors, and am trying to make this transition. Please help me with some questions about Screen Print?

1 - When we burn the screen, there will be only dots that do, or do not, pass ink. I got this right? I mean, there is no way of choosing different opacities of the same color and it get interpreted by screen, right? So how can I get different tones as in the following examples? That's where the halftone comes?

2 - Overprint works at Screen Print? I mean, the colors will mix?

3 - A mix of two other questions. Suppose I want to make shadows in a artwork. Black halftone will not help me get darker shades of other colors, am I right? I should make a new screen for each tone shade for each color I want. Got it right? Here what I mean:

How the hell? This is not a Screen Print job right?!

Thank you guys! This is driving me crazy.

 

[Celtic]

Yes, with halftones, you can achieve different shades and yes, therefore different opacities.
And yes, you can overprint, do CMYK printing (with CMYK inks only...they're transparent) as well as simulated process with standard inks. The last link that you listed would be a good candidate for 4 color process (cmyk) printing (with a white underbase).
Controlling halftones is best done with a RIP. I use AccuRip, myself.
There's lots of info in the forum (see search box) as well as a wealth of info on youtube.
Lots to learn !

 

[dynamikgraphics]

1) The thing to remember about a silk screen is that it acts in every sense as a stencil, basically just like the little cheap cut-out ones you can buy at Wally World, place on a surface, spray paint over and voila!

A silk screen works on the same principle, so each individual hole on the screen mesh has only two possible states: Open or closed. If it's open, ink passes through, if not...well, you get the idea.

Therefore, gradients, fountain fills, and varying tints of a particular color cannot be duplicated exactly as they appear on the computer screen. (A screen mesh hole can't be 60% open - either it is or it isn't.)

The way plate printing got around this was with using halftone patterns. The dots in the halftone pattern are small enough that they can fool the eye into thinking it's a smooth transition from one tone to another. If you look at both black & white and color images in your local newspaper closely, you will see that it's made up of halftones. Similar to screen printing, typeset printing utilize plates to apply each separate color (although they generally use CMYK).

So to answer your question, yes this is where halftones come into play. I definitely agree with Celtic in saying that you'll want a RIP software. In fact, if the printer you're using to print film positives isn't postscript compatible, you'll absolutely NEED a RIP software to convert gradients & tints into a halftone pattern.

Just a side note though - I'm not sure any of the images you posted were screen printed. They look more like they may have been DTG, but I could be wrong. I don't see any halftone patterns in the images, except for the bottom one, but I think it was a deliberate pattern for artistic reasons, not a necessary one for printing.

2) Yes, overprints work in screen printing. In fact, they're sometimes essential to making Simulated Process jobs look right, and they're ALWAYS essential to four color process printing. DO NOT flash a process ink after printing it!

3) The image you posted, if screen printed, would look the best if done using Simulated Process. It would need to be separated in Photoshop for screen printing.

 

[noiis]

1) The thing to remember about a silk screen is that it acts in every sense as a stencil, basically just like the little cheap cut-out ones you can buy at Wally World, place on a surface, spray paint over and voila!

A silk screen works on the same principle, so each individual hole on the screen mesh has only two possible states: Open or closed. If it's open, ink passes through, if not...well, you get the idea.

Therefore, gradients, fountain fills, and varying tints of a particular color cannot be duplicated exactly as they appear on the computer screen. (A screen mesh hole can't be 60% open - either it is or it isn't.)

The way plate printing got around this was with using halftone patterns. The dots in the halftone pattern are small enough that they can fool the eye into thinking it's a smooth transition from one tone to another. If you look at both black & white and color images in your local newspaper closely, you will see that it's made up of halftones. Similar to screen printing, typeset printing utilize plates to apply each separate color (although they generally use CMYK).

So to answer your question, yes this is where halftones come into play. I definitely agree with Celtic in saying that you'll want a RIP software. In fact, if the printer you're using to print film positives isn't postscript compatible, you'll absolutely NEED a RIP software to convert gradients & tints into a halftone pattern.

Just a side note though - I'm not sure any of the images you posted were screen printed. They look more like they may have been DTG, but I could be wrong. I don't see any halftone patterns in the images, except for the bottom one, but I think it was a deliberate pattern for artistic reasons, not a necessary one for printing.

2) Yes, overprints work in screen printing. In fact, they're sometimes essential to making Simulated Process jobs look right, and they're ALWAYS essential to four color process printing. DO NOT flash a process ink after printing it!

3) The image you posted, if screen printed, would look the best if done using Simulated Process. It would need to be separated in Photoshop for screen printing.

Thank you dynamikgraphics! Helped me understand these things a bit more.

 

[dynamikgraphics]

Thank you dynamikgraphics! Helped me understand these things a bit more.

No problem!

I should note one thing regarding my post: Never flash a four color process ink, specifically. Simulated process inks can be sometimes be flashed without affecting the final print.

Actually, "simulated process inks" is also a bit misleading - your plain ol' plastisol spot inks are used in sim process, so when it comes to the printing stage, sim process is basically no different than printing a multi-color vector design with gradients.