kopia lustrzana https://gitlab.com/sane-project/website
68 wiersze
3.0 KiB
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68 wiersze
3.0 KiB
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<!-- received="Fri Dec 19 06:42:51 1997 PST" -->
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<!-- sent="Fri, 19 Dec 1997 13:36:18 +0100 (MET)" -->
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<!-- name="becka@rz.uni-duesseldorf.de" -->
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<!-- email="becka@rz.uni-duesseldorf.de" -->
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<!-- subject="Re: Probable Bugs & Suggestions" -->
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<!-- id="m0xj1f8-0000XUC@charon.beck-sw.de" -->
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<!-- inreplyto="XFMail.971219121937.leidenfrost@dkrz.de" -->
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<title>sane-devel: Re: Probable Bugs & Suggestions</title>
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<h1>Re: Probable Bugs & Suggestions</h1>
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<a href="mailto:becka@rz.uni-duesseldorf.de"><i>becka@rz.uni-duesseldorf.de</i></a><br>
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<i>Fri, 19 Dec 1997 13:36:18 +0100 (MET)</i>
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<p>
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<li> <b>Messages sorted by:</b> <a href="date.html#113">[ date ]</a><a href="index.html#113">[ thread ]</a><a href="subject.html#113">[ subject ]</a><a href="author.html#113">[ author ]</a>
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<li> <b>Next message:</b> <a href="0114.html">Lutz Stege: "xscanimage won't start"</a>
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<li> <b>Previous message:</b> <a href="0112.html">Lutz Stege: "Re: How to turn off lamp in ScanJet IIcx"</a>
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<i>> The calibration would correct effect of a certain scanner printer combination.</i><br>
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<i>> However, it would be a general correction not only valid for a printed and</i><br>
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<i>> then rescanned image, which would indeed make not very much sense, but for any</i><br>
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<i>> image. </i><br>
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<p>
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No. This would assume the scanner has a gamma of 1.0.<br>
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<p>
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The "Right Thing to Do" (TM) would be :<br>
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<p>
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Get a printed reference color table. These are available from some photo <br>
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companies like Kodak.<br>
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<p>
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Now scan this one. As the color values of the table are known, the <br>
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response curves for the scanner can now be calculated.<br>
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<p>
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Now you have to compare the values with the monitor image and modify the<br>
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response curve until they match (assuming there is only a normal gamma <br>
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mismatch, there are simplified tests for that like the 50% value <-><br>
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black/100% comparision).<br>
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<p>
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To calibrate the printer, you now print and scan the result. As the scanner<br>
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is already calibrated, you can now calculate the printer response.<br>
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<p>
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I.e. you need to calibrate each device individually. otherwise you only get <br>
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a combined response which is only valid for the same "image path".<br>
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<p>
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CU,Andy<br>
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<p>
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<pre>
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--
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Andreas Beck | Email : <<a href="mailto:becka@sunserver1.rz.uni-duesseldorf.de">becka@sunserver1.rz.uni-duesseldorf.de</a>>
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<p>
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<pre>
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--
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Source code, list archive, and docs: <a href="http://www.mostang.com/sane/">http://www.mostang.com/sane/</a>
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To unsubscribe: echo unsubscribe sane-devel | mail <a href="mailto:majordomo@mostang.com">majordomo@mostang.com</a>
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</pre>
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<p>
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<ul>
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<!-- next="start" -->
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<li> <b>Next message:</b> <a href="0114.html">Lutz Stege: "xscanimage won't start"</a>
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<li> <b>Previous message:</b> <a href="0112.html">Lutz Stege: "Re: How to turn off lamp in ScanJet IIcx"</a>
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