Removing Halftone, & Enlarging old B/W pics

[paul -]

Help! How can I remove the halftone and moire from the small pics in

a 35 year old advertising flyer?<p>A local businessman has

rebuilt/enlarged his buildings several times over the last 40 years,

and nostalgia has him wanting poster-size enlargments of the growth

to display in his showrooms. His actual old photos, I have been

able to work with, scanning and enlarging in PS (my 30 day free trial

download of PS7 is expired, so I am working with Elements 2.0), and

having posters printed at Kinko's. But some of his most desirable

pictures are only available on a slick B&W flyer he printed up 35

years ago.<p>When I scan the pics (Canon 5000f, @1200, 600, 300, and

150 dpi, to see how each resolution handles the halftone), there are

various halftone and/or moire patterns appearing. I scanned all

resolutions except the 1200 dpi with the descreener activated on the

Canoscan, and it seems to help blend the halftone, but from what

creative combination of blurs/adjustments/etc can I get the cleanest

image that won't look like a greatly enlarged halftone print?

[emre]

<a href="http://www.creativepro.com/story/feature/10744.html">Scanning 101: No More Moire</a>

[jim_leonard]

First some hairbrained possibilities: Scan at a rather high resolution (much higher than the halftone size) then down sample to the same frequency as the halftone and then upsample to whatever resolution might do something for you. The more halfbaked idea is to try neatimage and see what it does if you try to convince it that the halftoning is the type of noise you're trying to get rid of.

 

The other option I see is to not even try to hide that it's an old half tone image. In fact flaunt it. Make it clear (in the photos) that this place has been around for a while and these are the photos available. You find this sort of thing often in museums where they took photos from newspapers and blew them up to 48 inches to a side. Scan the image without the descreening and in one of the highest resolutions you can and then sharpen it so you can see the edges of the halftoning clearly.

[kelly_flanigan1]

Scan with the "descreener" OFF; at the 600 dpi setting; 600 pixels/inch. Then there will be no moire pattern; but each dot will still be there. We do this all the time.

[sk_arts]

Scan at 600dpi+ reduce to 300dpi and size. If the more is still there in the form of speckles, in particular after sharpening, use dust and scrates at a low radius and high threshold. In the worst case you will need to use despeckle.

 

If this is the case jump to LAB. Use Median in A/B and low median and despeckle in L. Bluring A/B to some extent is OK, there almost always is no detail there. Bluring L however isn't.

[paul -]

Thanks for all of the tips!<p>I'll be working on these sometime in the next few days, and let you know how it works out.