The SL stands for OS X 10.6 aka Snow Leopard. I make the distinction with 10.5 aka Leopard, because the color management and printer driver stuff have been subtly modified in this revision. In 10.5 and with Aperture2 it was clear what to do independent of the printer. Now in 10.6 and with Aperture3 the final step of the color management has been delegated to the manufacturers printer driver, which is a world of pain. Most people with an Epson are still fighting; luckily I have a Canon but I am still not completely happy with the results on some non-Canon papers.
Mark Dubovoy is mainly referring to these printing problems in OS X with the hand-off from the application to the printer driver. The choice between sRGB and Adobe RGB comes down to the gamut of the image. If the image has a wide gamut to begin with it is better to go with Adobe, with rather "flat" images sRGB will utilize the bits better. I do mainly landscapes and have never been able to see the difference in a side by side comparison (maybe with a better monitor or printer...). So I go with sRGB mainly for the better compatibility between applications and devices. Adobe gets so easily tripped up somewhere in the workflow. The 16-bit versus 8-bit debate is also interesting. I never expected to see the difference, but I did, and always in deep blue skies. There the hue changes very subtly, and you require all the resolution you can get to prevent banding. The 8-bit images fall apart too easily when imported back into Aperture and subjected to final adjustments. I have started a thread in the Apple forums to find out how OS X handles (or should handle) images without a color profile. I always assumed it would default to sRGB, but it appears that it does not: the picture goes very flat if I strip an sRGB profile, so maybe Adobe is the default? As you say, slightly off topic. But this is the Hugin on OS X thread, so only slightly. Martin On Jul 14, 7:14 am, Eric O'Brien <[email protected]> wrote: > First, I guess missed something along the way. You (Martin) wrote > "...I have not yet discovered how images > without a profile are supposed to be handled in SL." Uh... what is > "SL?" > > Next, I don't know if there's a "default" color space in OS X, but if > you are going as far as using 16 bit deep images it seems counter > productive to use a color profile on the list that has pretty much the > smallest gamut. Of course, *eventually* you would probably want to > reduce the pano to 8 bit sRGB, but while you're working with it it > seems that a wider gamut such as Adobe RGB (1998) or ProPhoto RGB > would be better. In theory anyway... I don't know if ordinary persons > would be able to see any problems if you just kept using sRGB. (Adobe > RGB is much larger than sRGB and ProPhoto is much, much larger than > Adobe RGB.) > > Slightly off topic now, but it appears that there are circumstances on > the Mac where it is *impossible* to have "no" color management. See > <http://www.luminous-landscape.com/tutorials/solving.shtml > > > > eo > > On Jul 13, 2010, at 2:10 AM, Martin Middelhoek wrote: > > > > > Hi Harry, > > > thanks for the prompt response. > > > I export from Apple Aperture3 to 16-bit TIFF with the color profile > > sRGB IEC61966-2.1. It was my believe that sRGB was the default color > > space on OSX, so loosing the profile would not lead to disaster. > > Obviously I was wrong, but I have not yet discovered how images > > without a profile are supposed to be handled in SL. The finished > > pano's get imported back into Aperture for final adjustments and are > > then exported again as 8-bit TIFF and sRGB to Pano2VR. There also > > seems to be a color profile issue with that application which I will > > try to tackle next (or maybe it is just a scaling thing). > > > My whole flow is color managed and calibrated using icc-profiles all > > the way. As a stopgap I can use Preview to assign the correct profile > > and after that the input and output of Hugin are indistinguishable. I > > will try to figure out where the profile information is living in the > > images. In preview it shows up under General Info as "ColorSync > > profile: sRGB IEC61966-2.1" and under More info -> General as "Profile > > Name sRGB..". Is there any reason why exiftool -all:all can't find it, > > all groups and all writeable tags, right? > > > Martin > > > On Jul 13, 9:17 am, Harry van der Wolf <[email protected]> wrote: > >> 2010/7/13 Martin Middelhoek <[email protected]> > > >>> Hi Harry, > > >>> just found another bug: Hugin is stripping the color profile from > >>> the > >>> output file; or maybe not copying it. > > >>> I tried to use exiftool -all:all to copy it myself, but to no avail. > >>> Where is this going wrong? I seem to remember that this once worked. > > >>> This explains some of the weird color casts that I have been seeing. > > >>> Martin > > >> Hi Martin, > > >> These are the settings that exiftool should use: > >> #define HUGIN_EXIFTOOL_COPY_ARGS "- > >> ImageDescription -Make > >> -Model -Artist -W > >> hitePoint -Copyright -GPS:all -DateTimeOriginal -CreateDate - > >> UserComment > >> -ColorSpace -OwnerName -SerialNumber" > > >> These parameters are missing the "-icc_profile" and the "-XMP" > >> option tags > >> from exiftool. I think that's the biggest problem for you as > >> colorspace is > >> not the only parameter that should be used when using images with > >> color > >> profiles. > > >> IMO, Hugin could and should also use: "-IPTC:all -JFIF:all - > >> ColorSpace > >> -icc_profile -XMP" > >> I will post a separate mail about this asking users if I can add > >> these to > >> the trunk or whether there are some serious arguments why I should > >> do that. > > >> What kind of input files do you use and what kind of output files > >> (including > >> bit depths)? > >> Are you using icc color profiles?* > > >> *Harry* > > >> * > > > -- > > You received this message because you are subscribed to the Google > > Groups "Hugin and other free panoramic software" group. > > A list of frequently asked questions is available > > at:http://wiki.panotools.org/Hugin_FAQ > > To post to this group, send email to [email protected] > > To unsubscribe from this group, send email to > > [email protected] > > For more options, visit this group > > athttp://groups.google.com/group/hugin-ptx -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. 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