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<blockquote type="cite" cite="midilb1qm.wrctza@webmail.tuwien.ac.at">
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<pre wrap="">For example in img_03.jpg, Photoshop reports that the upper left
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<pre wrap=""><!---->corner
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<pre wrap="">has brightness 69%, the upper center has increased to brightness 80%,
and the upper right is again decreased to 67%.
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How do you check this exactly and how could I remove vignetting from
pictures? (GIMP?)
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I don't use GIMP very much and don't have a clue how to do it there.
Perhaps others can answer.<br>
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In Photoshop, to determine the brightness, just look in the "Info"
panel while running a cursor over the image. The Info panel is a tab
in a small dialog window along with Navigator and Histogram. It can be
made visible by menu entry Window | Info. It can be set to show
continuously any of several descriptions of the pixel under the cursor,
including RGB, HSB, CMYK, etc. I just reported the "B" value in HSB.<br>
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To remove the vignetting, I used Thomas Niemann's PTLens plugin for
Photoshop, with settings "amount=16, midpoint=0", those values
determined by repeated trials, checking the result as described above
and by looking at the result of a PTGui/enblend stitch. I presume that
the earlier Panorama Tools plugin Correct could do the same job, but
PTLens has a good preview that saves some work. One frame, img_01 was
also brighter than the others and required some level adjustment to
match. <br>
<blockquote type="cite" cite="midilb1qm.wrctza@webmail.tuwien.ac.at">
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<pre wrap="">See <a class="moz-txt-link-freetext" href="http://www.janrik.net/PanoPostings/20050816/20050816a.html">http://www.janrik.net/PanoPostings/20050816/20050816a.html</a> for
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<pre wrap=""><!---->examples.
Your pictures are linked to local files on your harddrive, we can't
access them ;)
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Fixed...thanks for letting me know. Netscape Composer strikes again --
its drag-and-drop always defaults to absolute path, not relative, and I
forgot to hit the checkbox to force it relative.<br>
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--Rik<br>
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