ViewSonic Monitor Calibration

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I have a ViewSonic G790 that I bought a few years ago and it has never presented any problems. Lately however, the scans from my Dimage Scan Speed are very dark and require quite a bit of manipulation. Before I reformatted my HD and removed the Adobe Photoshop color curves (that REALLY screwed things up), it displayed a correct balance IMO.

This now presents a major problem as some site where I have been uploading pictures for years, have begun rejecting them. Yes, they look dark on my monitor at work as well.

I have been advised of so many schemes for proper monitor calibration that I don't know who to believe. The last one was to turn-up the contrast to 100% and then reduce the brightness until I get a true back desktop background. Then I discovered the "Viewmatch Color" control on the monitor. It was set at 9300, so I expeimented with other options as follows: 6500 produced an off-white tint and 5000 was even worse. "User Color" gave a muddy white appearance.

Is this a monitor or a scanner problem. Minolta sez that the scanner cannot be calibrated and to use Photoshop (no thanks). Constantly setting the white point to remove the overall light magenta cast is a pain as well.

Any suggestions?

-- MikeB (airlinestuff@yahoo.com), March 09, 2000

Answers

It sounds like your monitor white-point has been set far too high when you created all your previous scans. Most monitors have a natural hardware white point of around 6000 to 7500 Kelvin, with 6500 being the preferred white point for the proposed sRGB standard. It's also my (limited) experience that 6500 is a good compromise across systems.

It may also be that you have a conflict of Gamma management handlers. Adobe Photoshop5 puts an Adobe Gamma application in the control panel of Windows, and the drivers for some video cards have their own Gamma controls; I know that ATI and 3Dfx cards do. You should set these to default if you use Adobe Gamma.

For a fuller explanation of colour management, you could do a lot worse than read Adobes explanation at:

Adobe Colour-management technical briefing

With particular reference to the sections on device profiles and the section on using Adobe gamma.

Hope this is of some help.

-- Pete Andrews (p.l.andrews@bham.ac.uk), March 10, 2000.


For information on calibrating monitors, try this site http://www.pp.clinet.fi/~timothy/aim/. This is the best site that I have found. It can be pretty slow so patience is required. I recently went through the monitor calibration exercise as outlined on these pages. I use a monitor colour temperature of 5000K because my light table has the same colour temperature. This allows me to easily colour match my transparencies with the monitor display

-- jonathan ratzlaff (jonathanr@clrtech.bc.ca), March 10, 2000.

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