How to turn digital images into printing plates?

Microsoft Publisher and Photoshop Elements

I think I have to ask a little more precisely.
What is you workflow while creating the plate? Do you vectorize or paint it by hand in Photoshop? Or do you work with reducing colors or anything like that? Or does anyone use a vector converter tool to have them vectorized automatically?
I’m a little confused how to get some good results…

First I recommend Gerald Lange’s book, “Printing Digital Type on the hand-operated flatbed cylinder press”.
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If it’s a halftone image scan it at high resolution 600ppi and reduce it in Photoshop to 300ppi.

If it’s line art, scan it in at 2400ppi. I use Adobe Illustrator CS3 to convert the raster image to vector using Live Trace. It does a great job.

Check the detail of the line art. Make sure your negative space is open enough or it may not be enough for the plate maker to hold and even if the plate maker can hold the image is it open enough to print.

I then do a save as .eps for Illustrator CS2 since most output bureaus may not be on CS3.

If it is a halftone image then scan it in and use Photoshop to change the mode to grayscale, save as a tiff. A tiff will be transparent in Illustrator if it overprints another color, plus you can colorize the tiff in Illustrator. You can ask the plate maker to output the plate at 65, 85, or 120 line screen. I’ve used all three. I even had an output at 45 line screen because my concept was to have big dots printed. But for more detailed work ask you plate maker. The finer the screen the tighter the image. With that said your control of ink and platen / cylinder pressure will all effect the outcome of the printed image, the image can plug up (too much ink).

Lots of people on the list will help.

Casey
iLP

What casey said!

“If it’s line art, scan it in at 2400ppi. I use Adobe Illustrator CS3 to convert the raster image to vector using Live Trace. It does a great job.”

Also you can do it with color photos and pick out the parts yo don’t want after you expand the appearence. You just have to adjust the tolerences of the live trace tool. I use this method when a designer from one of the local agencies sends me work that they created in Photoshop :P

Or if you want it more acurate you can trace the objects by hand with the pen tool. I use this most often when working with my own art so I don’t have to adjust jumpy lines that live trace leaves behind.

Thanks so much for the replies. You guys are awesome!
I tried the Live Trace in Illustrator and it works great. I only had time for a little test but I’m very pleased with the result so far.

Thanks!