Re: Mitsubishi Profiling Woes
Re: Mitsubishi Profiling Woes
- Subject: Re: Mitsubishi Profiling Woes
- From: William Hollingworth <email@hidden>
- Date: Fri, 23 Mar 2001 11:59:05 -0600
Doug
I have a few suggestions with your calibration problem:
You stated that the 2040 looked to have less contrast (indicating a higher
black level, and/or a lower gamma set in the LUTs), but yet in Optical you
can't match the luminance. I think this is where the problem lies. Do NOT
use the brightness control to try and match the "luminance" levels of
white. Use the brightness control only to match the black level. Once that
is set, DO NOT adjust brightness again. If the luminance level of white is
still not high enough, then use the Contrast control, or failing that,
increase the RGB gains slightly (at the same time try to maintain the
correct white point - use the Optical Colorimeter tool if necessary).
You also stated that your target luminance is around 112. If you are using
a white point of D50 or D65, then you can't achieve this kind of level for
very long. It is way way too high, especially for a 22" monitor. Typically
you should use a luminance level of around 80-85 cd/m^2.
Here are a few hints for adjusting (Optical runs you through most of these
steps automatically, however you may want to try manually):
1. First of all turn Optical off temporarily. Make sure nothing else is
setting the video card LUTs, such as Adobe gamma etc. Ideally you want
linear LUTs to be set.
2. Put up an identical image on both screens, ideally something like a gray
ramp.
3. Set the monitor Contrast to 100% and Brightness to 50%.
4. Visually compare the black levels of the darkest area of the gray ramp.
Use the brightness control to achieve the black level that you want.
Typically this will be something around 0.3 cd/m^2 or when black first
appears visible on the screen.
5. If the white points are different, use the OSD and make sure that both
are set to the same. I presume you are probably using D65 or D50 as your
white point, in which case use either Color 2 or Color 3 respectively from
the RGB OSD menu, then use the Color Reset to make sure the factory setting
is being used.
6. Compare the white level (luminance) of the white area of the gray ramp.
If they don't match, then first try adjusting the contrast DOWN on one
monitor to match the other. If you don't want to do that, then try
increasing the RGB gains UP on the lower monitor (again watch out to keep
the white point the same). If you use this technique, be sure not to
increase the RGB gains too much otherwise you will run into possible color
bleeding problems.
Keep in mind the limitations of the monitors. Just because a new monitor
will give you 112 cd/m^2, doesn't mean you should use it and expect it to
be able to achieve that for it's entire lifetime.
I hope this helps.
Regards
William Hollingworth
Senior Product Development Engineer
NEC-Mitsubishi Electronics Display of America, Inc.
http://www.necmitsubishi.com
-----Original Message-----
From: Doug Brightwell [mailto:email@hidden]
Sent: Thursday, March 22, 2001 7:36 PM
To: Colorsync List
Subject: Mitsubishi Profiling Woes
I have a 22" Mitsubishi 2040u and a LaCie electron 19 blue (also
Mitsubishi) that I use side by side with PhotoShop. I have tried to
profile them to look alike using PreCal/Optical and the Spyder
colorimeter.
Two problems:
1. I can't get the two monitors to match...
Typically, I profile the Mitsubishi first (since that's the monitor I
place the image window on in PhotoShop), and create a target. I then use
that target as the basis for profiling the LaCie monitor. I've also
tried profiling the LaCie monitor by itself, without using the
Mitsubishi profile as a target.
In either case, the LaCie is always cooler and richer (more contrast).
The Mitsubishi is always warmer and less contrasty. The desktop image on
both monitors is a gray gradient background, and the color of the gray
and the brightness of the gradient simply don't match.
I only use the LaCie for placing the palettes on, but obviously
something is off, and I have no idea which monitor is properly profiled.
2. I can no longer get the Mitsubishi monitor to meet the black level in
Optical, even with the brightness at 100% and the luminance set high in
PreCal (around 112), and... referencing a previous posting, even with
the black level set at "high" in the OSD. The monitor is less than 1
year old.
Any suggestions greatly appreciated...
Doug
--
Doug Brightwell
email@hidden