October 2013 - colorsync-users

Solid black to pure RGB black
by Jorge . 18 Oct '13

18 Oct '13

Hi, Adobe InDesign and Illustrator have a preference to display/export all blacks (including solid 100K blacks) as pure zero RGB black. While not color accurate in most usual CMYK color spaces I've come across, it is nevertheless the expected behavior when CMYK content is consumed on a screen not for soft-proofing purposes. Is there a way to accomplish the same when converting PDFs to sRGB JPEG? I have tried several rasterizers (Acrobat, Photoshop, Mac OS X' Quartz, Poppler), but in nether of them I found a setting/option, either on their UI, command-line options or programmatically, when used as a library to write my own renderer, to cheat with solid blacks and convert them to pure zero RGB. Note that I am using Perceptual rendering intent for all PDF objects (whatever their tag), so rich blacks do convert to pure RGB blacks. — Jorge

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NEC display problems
by Dennis Dunbar 18 Oct '13

18 Oct '13

Yesterday I got a call from a photographer who's having trouble with a new NEC 24" display and I'm hoping the folks on this list can shed some light on the situation for us. The photographer calibrated the display using the Adobe RGB setting in the Spectra View software, but began noticing that images on the web started to look overly saturated in the Reds, pretty much as if someone had assigned Adobe RGB to an sRGB image. This, of course, had her worrying about whether she has been over compensating for a color shift or somehow had been pushing the Reds too much in her images. NEC's suggestion was just to calibrate the display using the sRGB setting, but that defeats the purpose of having a wider gamut display, doesn't it? For what it's worth I have a Dell display in my studio that has a pretty wide gamut too, (comparable to Adobe RGB), and I've never seen this when viewing images on the web. So I'm feeling a little skeptical that it's just a case of using a wide gamut display to view images on the web. Any suggestions as to what could be the cause of the problem? And even more importantly what the solution might be? Thanks! Dennis Dunbar 310-463-1677 Blog: http://www.dunbardigital.com/blog/blog.php Website: http://www.dunbardigital.com Twitter: http://twitter.com/DennisDunbar

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Re: 8mm aperture
by Mike Strickler 12 Oct '13

12 Oct '13

Roger, the only other auto-measuring solution I can think of would be an i1 IO used in multi-measurement patch mode. This could be quite slow, however, as you would need at least 3 measurements per patch to get a decent average on a very noisy sample. If you have access to a Spectroscan this will not be much slower and will do a good job. > > Message: 1 > Date: Fri, 11 Oct 2013 13:11:36 -0400 > From: Roger Breton <graxx(a)videotron.ca> > To: Colorsync-users(a)lists.apple.com > Subject: 8mm aperture > Message-ID: <011a01cec6a4$f124cca0$d36e65e0$(a)videotron.ca> > Content-Type: text/plain; CHARSET=US-ASCII > > Hello fellow ColorSyncers, > > > > I require a large aperture opening 0/45 instrument for doing some low LPI > silk-screen characterization. > > Other than the excellent Barbieri SpectroLFP solution, is there anything > else that comes to your mind?

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8mm aperture
by Roger Breton 11 Oct '13

11 Oct '13

Hello fellow ColorSyncers, I require a large aperture opening 0/45 instrument for doing some low LPI silk-screen characterization. Other than the excellent Barbieri SpectroLFP solution, is there anything else that comes to your mind? Best / Roger

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