destripe

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	This is the original image, scanned at 800dpi (judging from the image this probably means only 200 physical dpi). You can "hardly" see the vertical stripes, can't you? (I tried to find a particularly bad example). Now let's get rid of them!
	This is what you see when you fire up the Plug-ins/Enhance/Destripe.. dialog. You can see a portion of the picture (use the scrollbars to move it around), with the destriping filter applied. Below it you have a slider and an associated number-entry. Move the slider (or enter a value) to see the effect of different filter widths. Width > 60 normally don't make much sense, unless the stripes are much wider than usual. Below is the same part of the image filtered with two other filter widths.

	I choose to go with 17. I hope you can see that most of the stripes have vanished or are at least much less visually disturbing. But wait! There is still a vertical line that annoys me, nearly in the middle!
	In cases like these, just select it with some additional border around it, like shown on the left. Then hit `Alt-F` (apply filter again), and it will vanish.
	This is the final picture. Compare it to the original (shown below for easy reference ;), and I hope you'll see the difference.
	Some tips: Most useful are values between 2 and 18. Large values tend to change the contrast too much, especially at the edges. You should always select parts of the image with "similar" lightness, as this is used to detect the stripes. Triangle shaped areas are especially bad.

destripe

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