Re: image defaults

From: Arnaud Calvo (arnaud@calvo-france.com)
Date: Wed Sep 06 2000 - 14:33:02 PDT

  • Next message: Arnaud Calvo: "driver for plustek"

    On 04-Sep-2000 Stephen Williams wrote:
    >
    > That Moire is caused by the interaction of the half-tone pattern in the
    > document and the sampling of either the scanner or the scaler. The frequency
    > of the pattern is the difference between the frequency of the halftone
    > on the page and the sample frequency of the scaled video.
    [cut]

    Without any doubt, the more complete answer !
    Congratulations !
    I appreciate very much your help (Johan Bengtsson & Peter Kirchgessner too, and
    others, but I don't remember the names, because I had too many answers :-)))

    I have to admitt I didn't understand all the explaination (my english's not
    rich enough !). But with a combination of all the suggestions, I removed the
    spots :-) (high res scan + blur + scale)

    I have another question (in fact 2) :
    - "The best hope, though, is to find the natural resolution of the scanner,
    and scan at that resolution." How can I find that ? Is there a precise way to
    do that ? No resolution gave me entire satisfaction... and perhaps the one that
    worked for this image won't work with another one...

    - "Scan at maximum resolution, then scale down (_not_ resize..) the image in the
    Gimp, and then sharpen it." What's the difference beetween "scale" and "resize"
    ? Is it a matter of "resolution" and "pixels" ? For this image, I used the
    option that allowed me to change the width from 900+ px to 800 px. How do you
    call that : resize, or scale ?

    Thanks

    -- 
    Arnaud Calvo <arnaud@calvo-france.com>
    49240 Avrillé
    

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