problem scanning newspaper or printed photographs

I am new to Photoshop 8 CS. I am scanning photographs for a book that will be offset printed, problem is that some of the original photographs are no longer available and I have to work from either newspaper prints or prints in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to remove this effect (at least I cannot find one). I have read that I should use a blur effect. Is there a filter in photoshop designed for this or a particular plug-in that will assist me?

On Tue, 1 Jun 2004 19:58:05 +1000, "Dugjak"
wrote:

I am new to Photoshop 8 CS. I am scanning photographs for a book that will be offset printed, problem is that some of the original photographs are no longer available and I have to work from either newspaper prints or prints in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to remove this effect (at least I cannot find one). I have read that I should use a blur effect. Is there a filter in photoshop designed for this or a particular plug-in that will assist me?

Are you asking where to find the blur filter or whether there is a de-moiré plugin?

Michael

My scanning software has a descreen option. I now understand that if I scan at a lower resolution (say 300 dpi instead of 600 dpi) I will get a better result in this situation.

Is there a de-moire plugin for photoshop. If so, what is it called?

"Xalinai" wrote in message

On Tue, 1 Jun 2004 19:58:05 +1000, "Dugjak"
wrote:

I am new to Photoshop 8 CS. I am scanning photographs for a book that

will

be offset printed, problem is that some of the original photographs are

no

longer available and I have to work from either newspaper prints or

prints

in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to remove this effect (at least I cannot find one). I have read that I

should

use a blur effect. Is there a filter in photoshop designed for this or a particular plug-in that will assist me?

Are you asking where to find the blur filter or whether there is a de-moir

In article <40bdbeea$0$8110$>,
"Dugjak" wrote:

My scanning software has a descreen option. I now understand that if I scan at a lower resolution (say 300 dpi instead of 600 dpi) I will get a better result in this situation.

Is there a de-moire plugin for photoshop. If so, what is it called?

The two main ones are called "Blur" and "Rotate". ;)

Seriously, you can sometimes reduce moiré by scanning an image slightly crooked and then straightening it out in Photoshop. Slight changes to the scan resolution can also make a big difference; a moiré that appears strong at 300 ppi might be much less apparent at 290 or 310 -- experiment! There's certainly no point to scanning a printed piece at a resolution more than twice the original screen ruling: say about 150 ppi for newspapers or 250-300 ppi for magazines; all you'll get is clearer renditions of the halftone dots, which you *don't* want to see in the final result.

--
Odysseus

Dugjak wrote:

I am new to Photoshop 8 CS. I am scanning photographs for a book that will be offset printed, problem is that some of the original photographs are no longer available and I have to work from either newspaper prints or prints in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to remove this effect (at least I cannot find one). I have read that I should use a blur effect. Is there a filter in photoshop designed for this or a particular plug-in that will assist me?

If this moiré' pattern does not change when zooming in/out....

A.) Try rotating the image maybe 45 degree the scanner platen.
B.) Try various scanning resolutions. I prefer 400 DPI.

Uni

Odysseus wrote:

In article <40bdbeea$0$8110$>,
"Dugjak" wrote:

My scanning software has a descreen option. I now understand that if I scan at a lower resolution (say 300 dpi instead of 600 dpi) I will get a better result in this situation.

Is there a de-moire plugin for photoshop. If so, what is it called?

The two main ones are called "Blur" and "Rotate". ;)
Seriously, you can sometimes reduce moiré by scanning an image slightly crooked and then straightening it out in Photoshop. Slight changes to the scan resolution can also make a big difference; a moiré that appears strong at 300 ppi might be much less apparent at 290 or 310 -- experiment!

Very good suggestions!!!

Uni

There's certainly no point to scanning a printed piece at a

resolution more than twice the original screen ruling: say about 150 ppi for newspapers or 250-300 ppi for magazines; all you'll get is clearer renditions of the halftone dots, which you *don't* want to see in the final result.

"Dugjak" wrote in message

I am new to Photoshop 8 CS. I am scanning photographs for a book that will be offset printed, problem is that some of the original photographs are no longer available and I have to work from either newspaper prints or prints in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to remove this effect (at least I cannot find one). I have read that I should use a blur effect. Is there a filter in photoshop designed for this or a particular plug-in that will assist me?

Try using the median filter with a width set to roughly the distance between adjacent blobs in the scan, then resize so that each blob becomes a pixel, and finally unsharp mask.

Regards,
Aaron Queenan.

On Tue, 1 Jun 2004 19:58:05 +1000, "Dugjak"
wrote:

[snip]

in existing books. When I do this I get a 'moire' effect and the printed scans are unsatisfactory. My scanning software does not have a control to

Nice tips here...

http://www.scantips.com/basics06.html

BTW, what scanning software are you using?

--
Kulvinder Singh Matharu
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