Hal V. Engel wrote:
You are correct about the devices supported by Argyll but I would have phrased it is as "the devices are either old and difficult to obtain or relatively expensive" since the Spectrolino is still in production but too expensive for many users (over. $3000 list).
From reports, I think that the DTP-94 is fairly compatible with the the DTP-92, giving the minor problem of the latest '94's being USB only :-), but it's hard to be certain without testing it. The DTP94 is currently available from Xrite. Getting this working with (say) Argyll might be relatively easy, although I'm not sure if it's available without the software bundle. The problems with the low cost instruments is as has been explained. In an attempt to lower cost, more "smarts" has been moved into the driver software. The manufacturers seem to universally then think that the exact way they driver their CCD sensors is "proprietary" and full of "secret sauce", and aren't prepared to let anyone else know how to talk to the hardware. As a side effect it also means that they don't have to keep the interface very constant or well documented. This leaves Linux type users in the usual position regarding drivers for hardware that the manufacturers have pretensions about (e.g. 3D graphics cards, wireless interface cards, etc.).
I don't think it is possible that this technique, or a variation of it, would result in profiles that are as good as those generated using a high quality measuring device. But I think that if everything were done in just the right way it might be possible to get profiles that are significantly better than those generated using LPROF "Rough Monitor profiler". In other words it has the potential to be a good "poor mans" technique and it may be the only option available until/unless one of the hardware vendors starts to provide measurement hardware interface software that works on Linux/Unix/BSD machines.
The biggest technical problem is that you have no spectral calibration for the camera. It is effectively a "colorimeter", and colorimeter instruments work fine for characterizing displays, if you know the spectral characteristics of both the display and the colorimeter (all the low cost display instruments are probably colorimeters, although they probably have a closer to XYZ response than most of the cameras out there.) Profiling the camera with an IT8 is not going to help a lot I would imagine, since the reflective target is broad band, and most displays are narrow band sources (spectrally, the chart and the display are a very long way apart). Graeme Gill. ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
