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Ronald
05-25-2011, 07:30 PM
I'm getting freelance work from a local screen print shop - to test my skills - which will likely lead to a full-time position at the company. Even though I haven't begun my second substantial job, given to me on Saturday, the owner emailed me five more small jobs just this afternoon.

The incomplete job I speak of involves creating original art heavily based on another shirt (attached as "uniondesign.jpg"). But it includes lots of tonal variation, as though airbrushed, and I'm not sure how to approach creating and separating it. Tutorials/videos online usually just promote a software plugin, and I'll probably be limited to Photoshop.

I'm thinking I'll create much of the black art on bristol board in ink, scan that (600 dpi?), then add more airbrushed black and a layer of blue in Photoshop. Among other differences, I need to incorporate an American flag; the red shirt would just need black, white, and blue spot colors.

Any help on this process (including how to scan art, color in PS, and separate) would be greatly appreciated.

terrie
05-25-2011, 08:07 PM
I'd definitely scan it at 600ppi because it will give you greater flexibility in later sizing.

Just off the top of my head, it might be useful to look into using layer masks which will allow you play with how much or how little of the airbrushed layers to show thorugh and also allow you to play with the visibilty of the flag.

Can't help you with the separation as it's something I don't know much about because I never have to use them because I do all my work and printing in RGB but hopefully someone with knowledge about that will pop in...

Terrie

groucho
05-29-2011, 01:33 PM
Those can be fairly deep subjects with many options and pitfalls, you might want to get a couple of Photoshop books and get detailed answers.

"Simple" things like separations can be impossible or a best extremely time consuming depending on little things like how the original art was made. If an original is made with "5% black" and "10% black" etc. and each one is made as a spot color, simple separations can result in 20 separate spot colors--rather than one black plate. (Yes, I've seen that happen. The artist couldn't understand why they got back 40 plates instead of four.)
Then you have a JPG file, a bitmap. You won't be able to work with that the same way as an original EPS file, either. Now you've got to chase pixels.
If you're actually airbrushing? It may be simplest to airbrush on acetates over a print of the art. Then scan in your acetates as originals, and add in the type and other computer-generated features--all new to match the original--at the end.
Or, scan in the original and do your new work on new layers, with transparency adjusted as needed, in Photoshop. Assuming you can get an original with enough quality to base your new image on it.

Whether the original artwork is just lost over the years, or the printer can't ask for it because he's working under the table...you may have quite a task ahead of you.

Either way a book that explains the options and possibilities is more likely to give you a wider range of answers and options.

Ronald
05-30-2011, 09:53 AM
"Simple" things like separations can be impossible or a best extremely time consuming depending on little things like how the original art was made. If an original is made with "5% black" and "10% black" etc. and each one is made as a spot color, simple separations can result in 20 separate spot colors--rather than one black plate. (Yes, I've seen that happen. The artist couldn't understand why they got back 40 plates instead of four.)
Then you have a JPG file, a bitmap. You won't be able to work with that the same way as an original EPS file, either. Now you've got to chase pixels.

If you're actually airbrushing? It may be simplest to airbrush on acetates over a print of the art. Then scan in your acetates as originals, and add in the type and other computer-generated features--all new to match the original--at the end.

Or, scan in the original and do your new work on new layers, with transparency adjusted as needed, in Photoshop. Assuming you can get an original with enough quality to base your new image on it.

Thanks, groucho. So far, I've drawn the basic art in pencil. The client strongly approved of the design, so now I need to ink it and scan for further coloring in Photoshop. The shop owner told me his main artist airbrushes in Photoshop and that the current project would be 4-5 colors: white (highlights), antique/bone white, black, and 1 or 2 blues. Hopefully any inked crosshatching won't stylistically interfere with the airbrushed gradations.

I figured that after all the coloring is finished, maybe the color layers are converted to greyscale and given a halftone effect? I was told just to color it for now and not worry about converting separations. I'm going to the shop tomorrow morning, hopefully with the art completed, to see firsthand how their artist handles these projects.

terrie
05-30-2011, 02:03 PM
ronald: maybe the color layers are converted to greyscale and given a halftone effect?You can experiment with this yourself but use a Channel Mixer adjustment layer--click on the "Monochrome" option--rather than using Image > Mode > Greyscale...

What you want to do first is to take a look at the individual channels in the Channels palette to see which one gives you the "best" result and start with that channel in Channel Mixer and then subtract from your base channel (reduce the percentage from 100%) and add to your other channels. The rule of thumb with Channel Mixer is that the sum of all the channels should add up to 100% but I sometimes find that using a higher total percentage can give you a better coverted image--just depends on the image itself so experiment a bit with the percentages.

In general, I find that using Channel Mixer gives me better greyscale results than using Image > Mode > Greyscale.

You may also find that after adding the Channel Mixer adjustment layer, doing either a Levels and/or Curves adjustment layer gives the greyscale that last little tweak...

Using Channel Mixer is one reason why you want to scan your drawing in RGB--of course you will be adding color later but, scanning the original in RGB, gives you greater flexibilty later (as does scanning at 600ppi/dpi)...

Hope that helps...

Terrie