# Re: Umax Astra 6x0S - CCD distance - Do they *really* do this that way ?

Oliver.Rauch@Wolfsburg.DE
Thu, 19 Feb 1998 17:18:04 +0100 (MET)

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Hi,

> us->CCD_distance = us->y_resolution / 37.5 +.5;
As long as us->CCD_distance is type integer, you get an 8 and that
is ccd_distance!

> This way, you get correct images at 4 different resolutions (75, 150,
> 225 and 300 dpi).
I know 300 dpi and 150 dpi work with my version, 75 should work too, but
is not tested, 225 dpi don't know!

> After this change, all images (except the 4 resolutions above) need to
> be ccd-corrected, but with a float ccd value, -1 < ccd < 1

I think we have to calculate when does a ccd is positioned over a
line that shall be scanned, then the scan-line is sent in that moment
to the computer.
If we use 300, 150 or 75 dpi, we get the data in correct order,
if we use other resolutions, the lines are scanned and sent
in an other order!

Bye
Oliver

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