Pierre Willenbrock schrieb: > Luke Campagnola schrieb: >> It's been a while since I originally brought this up, but I've pulled out >> the ol' scanner for another go. >> to recap: color calibration isn't quite right on my canon lide35--the dark >> colors drop out to black. I turned on SCAN_FLAG_DISABLE_SHADING as you >> instructed, and as you predicted this recovered my lost dark colors. Where >> should I go from here? Should I crank up SANE_DEBUG_GENESYS and send you >> the >> scanimage output and *.pnm files? >> >> Thanks, Luke >> > > Hi Luke, > > Did you try with sane from cvs? There have been some bug fixes. If that > does not show the dark colors, use SANE_DEBUG_GENESYS=255 and > SANE_DEBUG_GENESYS_GL841=255 with scanimage in color mode, and send the > resulting error output and the generated .pnms. > > Regards, > Pierre
The patch i attached will not apply -- try this one instead. > >> On 3/7/06, Pierre Willenbrock <pie...@pirsoft.dnsalias.org> wrote: >>>> - Color reproduction is better with the sane driver than the windows >>> driver, >>>> which tends to boost the reds way too much (yaay) >>>> - Brightness reproduction is quite poor with the sane driver. It seems >>> that >>>> darker colors just drop off to black very quickly. >>> A better tool to determine if the bright and dark colors are correctly >>> reproduced is a histogram tool. You can clearly see, if there is still >>> room at the bottom and top of the histogram(not too much, as you still >>> want some useable color values ;-)). >>> >>> This reveals that dark colors are cut off for the sane driver, but it >>> also shows that the windows driver cuts off bright colors. >>> >>> Anyway, it shows a incorrect calibration on the sane side. >> <snip> >> >>> To get an unshaded image, you can disable shading correction in >>> gl841_init_regs_for_scan by changing the flags(last parameter to >>> gl841_init_scan_regs, currently 0) to include SCAN_FLAG_DISABLE_SHADING. >>> >>> If the image then still shows dark colors cut off, the offset/exposure >>> calibration is to blame. Otherwise the shading calibration calculates >>> incorrect data(which i suspect). >>> >>> I should put this lengthy description online somewhere.. >>> >>> Regards, >>> Pierre >>> > -------------- next part -------------- A non-text attachment was scrubbed... Name: new-calib.patch Type: text/x-patch Size: 14689 bytes Desc: not available Url : http://lists.alioth.debian.org/pipermail/sane-devel/attachments/20070114/b08c478c/new-calib-0001.bin From olaf.meeuwis...@avasys.jp Mon Jan 15 00:56:42 2007 From: olaf.meeuwis...@avasys.jp (Olaf Meeuwissen) Date: Mon Jan 15 00:57:42 2007 Subject: [sane-devel] Re: Epson V350 PHOTO ? In-Reply-To: <25592666.60937f96.45a76833.62...@o2.pl> (piotr n.'s message of "Fri, 12 Jan 2007 11:51:31 +0100") References: <20070108230338.gj3...@abridgegame.org> <20070111131322.436e35b5@inspiron> <877ivtyw0q....@geek.avasys.jp> <25592666.60937f96.45a76833.62...@o2.pl> Message-ID: <87wt3pqi11....@geek.avasys.jp> "piotr_n" <piot...@o2.pl> writes: > Hi, Hi, > I,ve read notes about troubles with an Epson V100 "working" with > linux. To sum up it seems not working with this system perfectly. As > a potential buyer of Epson V350 I'd like to ask if this model has or > hasn't problem with linux. My question is about full support this > scanner by sane system (or other) as a model with different chip > (GT-F700) in contrast to V100 (GT-F650) AFAIK, the V350 as well as the V100 are only supported via iscan's epkowa backend. Both require a binary-only non-free plugin that is only available for i386 machines. If you can live with that, the V350 works under linux. # The GT-F700 and GT-F650 are the model names for the Japanese market. # They do not refer to the chipset. Hope this helps, -- Olaf Meeuwissen EPSON AVASYS Corporation, SE1 FSF Associate Member #1962 sign up at http://member.fsf.org/ GnuPG key: 6BE37D90/AB6B 0D1F 99E7 1BF5 EB97 976A 16C7 F27D 6BE3 7D90 Penguin's lib! -- I hack, therefore I am -- LPIC-2
