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Re: Colorsync-users Digest, Vol 2, Issue 195

Hi Carlo,

LStar is not a gamma curve. Gamma is something "historic" since all CRTs have a native (hardware) gamma characteristic, that can be corrected to a different gamma with a relatively simple equation. 
LStar is a visually linear, equidistant curve, that measn that there is a linear relation between RGB values and the resulting luminance on the monitor. If you increase your RGB values by lets say 10, the resulting increase in luminance will be ca. 4 L*, regardless where  you start off - in the shadows, midtones or highlights. With a gamma calibration you have different increases of luminance in different areas. In other words, your luminance curve is compressed in someparts and stretched in others. This can result in banding.
The best companion for a linear calibration, of course, is a linear working space like LStar-RGB (download from www.LStar-RGB.com), same gamut as eciRGB.icc, baut linear tonal response curve instead of gamma 1.8.

basICColor does not suggest that luminance is set to maximum. It is true that this is the default setting, when you satrt the software, but you can enter any luminance value. With DDC-CI capable monitors luminance is set in the monitor hardware automatically.

Best regards,

Karl Koch

P.S.: EIZO has just released the CG210 that has the same controller as the CG220, that means 3 independant 10bit LUTs with 14bit processing. basICColor display is the first independent software solution that supports hardware calibration for these monitors.

Am 16.05.2005 um 21:04 schrieb email@hidden:

After reading so much  about the wonders of calibrating the  Eizo  CG 
21 with basICColor 3.0.4 I decided to give it a try...

the only thing that bugs me is the advice to calibrate to a GAMMA L* 
(LStar)  as suggested by the User Guide
just a new term I never encountered before...
is it advisable to do that?


thanks

Carlo



PS

It also seems to me that basICColor softly suggest that a Luminance set 
to maximum it's also advisable or is it just my poor English?



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