We have a 7800 at school and this is a CMYK device, the driver is not RGB. But you need to turn color management off to get what you want in the driver's printing option. Works like a charm. / Roger -----Original Message----- From: colorsync-users-bounces+graxx=videotron.ca@lists.apple.com [mailto:colorsync-users-bounces+graxx=videotron.ca@lists.apple.com] On Behalf Of Lorenzo Ridolfi Sent: 7 avril 2016 10:40 To: colorsync-users@lists.apple.com Subject: Sending CMYK data to PS Printer Hi, I’m working with a Xerox Phaser 7800 with no RIP, using the default Xerox driver. Does anybody know if Acrobat sends the PDF data as CMYK to the PS driver by default? I’m afraid the driver may convert the CMYK data to RGB. Is any way to check if the data sent to the printer is really CMYK? I’m thinking in printing CMY versus K values to check. Thanks, Lorenzo _______________________________________________ Do not post admin requests to the list. They will be ignored. Colorsync-users mailing list (Colorsync-users@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/graxx%40videotron.ca This email sent to graxx@videotron.ca
On Apr 7, 2016, at 9:26 AM, Roger Breton <graxx@videotron.ca> wrote:
We have a 7800 at school and this is a CMYK device, the driver is not RGB.
I believe strongly that it is as are AFAIK all GDI/Quickdraw drivers. If you send the Epson driver CMYK data, it will convert it, poorly, back to RGB in the 'pipeline'. The results are not pretty. Andrew Rodney http://www.digitaldog.net/
That’s exactly what I’m afraid of… I’ll print 100% CMY and K only patches to try to check if the driver is not converting everything to RGB. Thanks, Lorenzo
On Apr 7, 2016, at 12:48, Andrew Rodney <andrew@digitaldog.net> wrote:
I believe strongly that it is as are AFAIK all GDI/Quickdraw drivers. If you send the Epson driver CMYK data, it will convert it, poorly, back to RGB in the 'pipeline'. The results are not pretty.
Andrew Rodney http://www.digitaldog.net/ _______________________________________________ Do not post admin requests to the list. They will be ignored. Colorsync-users mailing list (Colorsync-users@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/colorsync-users/lorenzo%40mail.com
This email sent to lorenzo@mail.com
We have a 7800 at school and this is a CMYK device, the driver is not RGB.
OK let’s just clarify that this is a Xerox Phaser 7800, not an Epson! While traditional Quickdraw printer drivers require us to generate RGB profiles, Postscript printer drivers like the Phaser’s require us to make CMYK profiles. Some laser printers offer both Quickdraw and Postscript drivers for the same printer so it’s important to be aware of this… In any case one can always print a visual IT8.4 target without color management and look at the CMYK ramps under a loupe. If they utilize a single color for each of these ramps then you’ve got the green light to profile in CMYK. If not, you’ve got a problem to address. Adobe Color Printing Utility typically fails for me with Postscript drivers so I print my targets from Photoshop by assigning the circa 1991 US Sheetfed Coated v2 Profile to the target and print with the same profile. Although this null transform trick doesn’t work with RGB profiling targets, it does work for CMYK targets. I’ve profiled a fair amount of 7800’s and have found i1Profiler work surprisingly well especially if you maximize the black separation, thereby reducing the dry toner’s inherent metamerism issues. Scott Martin www.on-sight.com
On Apr 8, 2016, at 8:36 AM, Scott Martin <scott@on-sight.com> wrote:
OK let’s just clarify that this is a Xerox Phaser 7800, not an Epson!
Ah, that helps, sorry for the assumption about the 7800 being an Epson, using that driver. Andrew Rodney http://www.digitaldog.net/
participants (4)
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Andrew Rodney
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Lorenzo Ridolfi
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Roger Breton
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Scott Martin