Re: Re: [Gimp-user] Gimp and prepress functions
Hi, Jean-Luc Coulon (f5ibh) [EMAIL PROTECTED] writes: GIMP 2.0 comes with a color proof display filter that uses ICC color profiles to simulate a proof on your monitor. Support for such filters is new in 2.0 and for the future it is planned to integrate display filter modules better into the workflow. I've used the colour proof display filter with profiles I built with an eye one spectrophotometer from GretagMacbeth. This allows be at least to have the right colours on the screen while the photos I get from my digital slr camera. This is one step in the right direction. But only the display is affected: the output is left unmodified. There's also things going into that direction. There are two enhanced TIFF plug-ins that work with color profiles and we will look to get this functionality included in the GIMP distribution. For the more long-term future, support for other colorspaces than RGB and for more color-depth than 8bit/channel is planned and is actually already being worked on. Sven ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re : Re : [Gimp-user] Gimp and prepress functions
Le 24.03.2004 14:28, Sven Neumann a écrit : Hi, Jean-Luc Coulon (f5ibh) [EMAIL PROTECTED] writes: GIMP 2.0 comes with a color proof display filter that uses ICC color profiles to simulate a proof on your monitor. Support for such filters is new in 2.0 and for the future it is planned to integrate display filter modules better into the workflow. I've used the colour proof display filter with profiles I built with an eye one spectrophotometer from GretagMacbeth. This allows be at least to have the right colours on the screen while the photos I get from my digital slr camera. This is one step in the right direction. But only the display is affected: the output is left unmodified. There's also things going into that direction. There are two enhanced TIFF plug-ins that work with color profiles and we will look to get this functionality included in the GIMP distribution. For the more long-term future, support for other colorspaces than RGB and for more color-depth than 8bit/channel is planned and is actually already being worked on. Sven That is good news. - As my camera support 12bits depth there will be more dynamic range to do the post-processing (together with dcraw from Dave Coffin). - When I ask for prints to colormailer pro service they ask to have the colour space embedded in the file otherwise the pictures are interpreted by the lab and there is some colour shift. -- Regards - Jean-Luc pgp0.pgp Description: PGP signature
[Gimp-user] Gimp and prepress functions
I recognize that Gimp is web-centric, and that enhanced prepress capabilities are somewhere in the future. However some of us do use Gimp for images ending up on the printed page. And critics of Gimp and Open Source software in general jump on prepress issues as a point of criticism. In addition to CMYK the issue of ICC color profiles has been raised. Photoshop offers several profiles for e.g., coated paper, uncoated paper and so on. It is clumsy to develop in Gimp, and then transfer to Photoshop just for profiling. What are the prospects of doing something in this area? Is any of it on the agenda? -- John Culleton Able Typesetters and Indexers http://wexfordpress.com ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
John Culleton wrote: I recognize that Gimp is web-centric, and that enhanced prepress capabilities are somewhere in the future. However some of us do use Gimp for images ending up on the printed page. And critics of Gimp and Open Source software in general jump on prepress issues as a point of criticism. In addition to CMYK the issue of ICC color profiles has been raised. Photoshop offers several profiles for e.g., coated paper, uncoated paper and so on. It is clumsy to develop in Gimp, and then transfer to Photoshop just for profiling. What are the prospects of doing something in this area? Is any of it on the agenda? Someone would have to develop the profiles. The way Photoshop does it is by buying printers and doing test prints and gathering colorimetric data. The GIMP developers are short on people who have access to colorimetry labs, not to mention lots of printers. A lot of the processes that go into prepress are tied up in patent and trade secret law. Getting those processes into the GIMP will be no easy task. Kelly ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
Kelly Martin [EMAIL PROTECTED] wrote: Someone would have to develop the profiles. The way Photoshop does it is by buying printers and doing test prints and gathering colorimetric data. The GIMP developers are short on people who have access to colorimetry labs, not to mention lots of printers. A lot of the processes that go into prepress are tied up in patent and trade secret law. Getting those processes into the GIMP will be no easy task. This is a furphy. Generating the profiles is quite different from using them. There are existing libraries (e.g. lcms) to convert between colour spaces (defined by profiles) and there's even a Gimp plug-in to do this. There is even software for generating profiles for printers/scanners/etc (not part of the Gimp, but it doesn't have to be). For accurate colour work you typically need to profile your own devices, as each has a slightly different colour response (e.g. for a printer it depends on the driver settings, the ink, and the paper choices). Monitors in particular constantly change their behaviour and need to be reprofiled regularly. Good print labs profile their devices and provide the profiles to their clients. It's not up to the Gimp to generate profiles, it's up to the Gimp to use them. Unfortunately Gimp has a way to go before it has a concept of your monitor colour space (and dynamically converting displayed images into that colour space) and a colour space for each image. This is something that Photoshop (and most of the other Adobe software) does very well. The Gimp has a plain model where there is only one colour space: your monitor's. Everything is dealt with as just RGB (disregarding the HSV/etc composition/decomposition feature) and sent to your monitor as-is. I think a more-sophisticated model is required to support a colour-managed workflow (and things like 16-bit support, CMYK, L*a*b, etc are just part of that). Other projects like CinePaint (nee FilmGimp) are making progress on this. Hopefully the Gimp will catch up. But I don't think patent and trade secret law has much to do with it. __ David Burren ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
Hi, John Culleton [EMAIL PROTECTED] writes: In addition to CMYK the issue of ICC color profiles has been raised. Photoshop offers several profiles for e.g., coated paper, uncoated paper and so on. It is clumsy to develop in Gimp, and then transfer to Photoshop just for profiling. What are the prospects of doing something in this area? Is any of it on the agenda? GIMP 2.0 comes with a color proof display filter that uses ICC color profiles to simulate a proof on your monitor. Support for such filters is new in 2.0 and for the future it is planned to integrate display filter modules better into the workflow. Sven ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
David Burren wrote: and need to be reprofiled regularly. Good print labs profile their devices and provide the profiles to their clients. It's not up to the Gimp to generate profiles, it's up to the Gimp to use them. My gf used to work for a large prepress company. They spent a lot of money generating and validating matching profiles, and they're not going to just give them to anyone. If you want them, you pay for them. That's where the trade secret law comes in. Kelly ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
In my recent experience, ICC (or ICM or both?) profiles are included with a lot of newer hardware, and/or they can be downloaded from the manufacturer's web sites. That seems to be increasingly prevelant, at least as far as devices with Windows support are concerned. I don't know much about these profiles, but it appears that these can be used across multiple applications. Under Windows, files with .icc and .icm extensions are normally installed under the %windir%\system32\spool\drivers\color directory. Right now, there are about 50 of those files installed on one of my machines, including a significant number that appear to be for hardware that I don't even own. My first conclusion is that a signifcant number of color profiles appear to now be either included with hardware (such as monitors, scanners, and printers), included with various applications (e.g Corel Draw), and/or included with the Windows OS. My second conclusion is that it seems reasonable that the Gimp *might* be able to use these, since they don't appear to be application-specific. However, I don't know anything about the format or content of those files, nor how to go about selecting and using the profile that is appropriate for a particular device. So, I don't know whether these same files might be usable under Linux for example, nor how difficult it might be to enable use of them from the gimp. Mainly I just wanted to offer these observations in case they might be applicable to the availability issue. s/KAM - Original Message - From: Kelly Martin [EMAIL PROTECTED] To: David Burren [EMAIL PROTECTED] Cc: John Culleton [EMAIL PROTECTED]; GIMPUser [EMAIL PROTECTED] Sent: Tuesday, March 23, 2004 7:10 PM Subject: Re: [Gimp-user] Gimp and prepress functions David Burren wrote: and need to be reprofiled regularly. Good print labs profile their devices and provide the profiles to their clients. It's not up to the Gimp to generate profiles, it's up to the Gimp to use them. My gf used to work for a large prepress company. They spent a lot of money generating and validating matching profiles, and they're not going to just give them to anyone. If you want them, you pay for them. That's where the trade secret law comes in. Kelly ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
Kelly Martin [EMAIL PROTECTED] wrote: My gf used to work for a large prepress company. They spent a lot of money generating and validating matching profiles, and they're not going to just give them to anyone. If you want them, you pay for them. This is silly. The profiles would be for their specific machines, and would be useless with anyone else's (even with the same make hardware, as the knobs and dials would probably not be in standard positions). The choice of ink and paper stock are also factors. I'm not saying the prepress company wouldn't do it, just that I think it would be a completely silly reason for not supplying the target profile. Even if they did not want to provide the final profiles, if they want any chance of supporting a digital colour-managed workflow they would have to accept files tagged with other profiles (e.g. AdobeRGB, sRGB, ProPhotoRGB, various CMYK colour spaces, etc) and do the conversion in-house. One of the labs I deal with has its own intermediate colour space that it gets us to convert to, so internally they can manage the choice of printer/paper/etc for each job and update the target profiles whenever they calibrate the machines (without having to send them out to all the clients). Those intermediate colour spaces should be available to the Gimp (although there _are_ copyright considerations with the profiles). The format of these ICC profiles is defined in a standard, and the lcms library already knows how to deal with them. Cheers __ David ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress functions
David Burren wrote: This is silly. The profiles would be for their specific machines, and would be useless with anyone else's (even with the same make hardware, as the knobs and dials would probably not be in standard positions). The choice of ink and paper stock are also factors. I'm not saying the prepress company wouldn't do it, just that I think it would be a completely silly reason for not supplying the target profile. Indeed. Their clients (Fortune 500 companies, every last one of them) pay dearly for them to develop exact color matching profiles that match the specific printing presses, stock, and inks they use. Kelly ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re : [Gimp-user] Gimp and prepress functions
Le 24.03.2004 01:59, Sven Neumann a écrit : Hi, John Culleton [EMAIL PROTECTED] writes: In addition to CMYK the issue of ICC color profiles has been raised. Photoshop offers several profiles for e.g., coated paper, uncoated paper and so on. It is clumsy to develop in Gimp, and then transfer to Photoshop just for profiling. What are the prospects of doing something in this area? Is any of it on the agenda? GIMP 2.0 comes with a color proof display filter that uses ICC color profiles to simulate a proof on your monitor. Support for such filters is new in 2.0 and for the future it is planned to integrate display filter modules better into the workflow. I've used the colour proof display filter with profiles I built with an eye one spectrophotometer from GretagMacbeth. This allows be at least to have the right colours on the screen while the photos I get from my digital slr camera. This is one step in the right direction. But only the display is affected: the output is left unmodified. There is also the need (with digital photography in mind and this is a growing usage of tools like The Gimp) to work in a given colour space (i.e. sRGB or Adobe RBG 1998) and the used colour space should be included in the final picture ready to prints: most of the labs need this information so that you get the picture unmodified. Without the colour space information, most of the time, the colours are shifted and your work is ruined. Sven pgp0.pgp Description: PGP signature
[Gimp-user] gimp and prepress
The books all admit that Gimp is too weak to compete in the world of color prepress work with the likes of Photoshop. Is there a currrent effort to strengthen Gimp in this area? Or is it just to far a stretch? John Culleton ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] gimp and prepress
On Tue, 2001-10-09 at 16:28, John culleton wrote: The books all admit that Gimp is too weak to compete in the world of color prepress work with the likes of Photoshop. Is there a currrent effort to strengthen Gimp in this area? Or is it just to far a stretch? From what I understand, is that it is a lot of patent issues. There isn't the right stuff available to base GIMP stuff on. Or something like that. A smart developer could explain it better. ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] gimp and prepress
On Tue, 2001-10-09 at 16:28, John culleton wrote: The books all admit that Gimp is too weak to compete in the world of color prepress work with the likes of Photoshop. Is there a currrent effort to strengthen Gimp in this area? Or is it just to far a stretch? From what I understand, is that it is a lot of patent issues. There isn't the right stuff available to base GIMP stuff on. Or something like that. A smart developer could explain it better. ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Gimp and prepress
On Friday 14 September 2001 10:02, you wrote: On Thu, Sep 13, 2001 at 01:50:27PM -0400, John culleton wrote: I know that Gimp is considered relatively weak in the prepress area. So I pose the following questions: If an image is created in Gimp, converted at the end to CMYK, and saved as an EPS file, is the result acceptable for prepress use? Converted at the end to CMYK by what? GIMP can't make acceptable separations. Zach Good point. However I have submitted to my customer and indirectly to a press a PS document with spot color described in CMYK terms and they could handle it. CMYK is one thing, color separations another. I am not running a print shop. I submit to print shops. If the print shop can't handle my PS file with gimp-produced CMYK eps files then I am in trouble. If they can make their own separations from my material then I am OK. So in this context, what are your thoughts? John Culleton WexfordPress ___ Gimp-user mailing list [EMAIL PROTECTED] http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
