"For best viewing, adjust your monitor until you can see all the squares."

[mikemeister_admin]

I set up my ViewSonic EF70 monitor with Mac Tiger's Display Calibrator.

After matching all the patches while squinting my eyes, and choosing 2.2 gamma & 6500 degree white point, I still can't distinguish the two leftmost black squares at the bottom of every curvemeister.com page.

To be able to distinguish them, I have to increase the monitor brightness way too high for the Display Adjustment (where you decrease the brightness until the center oval barely can be seen within the black box).

(Yeah, yeah, yeah, we'll be getting a suction-cup hardware colorimeter calibrator soon, but I'll bet it won't make a difference in curvemeister.com's black squares.)

What do you think?

[-default]

The squares at the bottom of the curvemeister are evenly divided into values of 0, 17, 34, etc, up to 255. 

Here is a collection of other monitor adjustment patterns, for comparison:
http://www.help4web.net/setup/mire.html

If you are unable to distinguish the bottom two squares, then I think your monitor is adjusted slightly too dark.  I doubt this will make much of a difference in the accuracy of your views, but in many cases you will not be able to see shadow detail, and your images will probably appear overly gray in the shadows to others.

[mikemeister_admin]

OK, I finally got it calibrated so I can see the two leftmost darkest squares.

The problem was the 6500 degree compensated color temperature: it was the very *last* step in the series of calibrations and it was reducing the shadow contrast, obliterating the last two squares that clearly were distinct in the *first* step of setting the brightness.

It was an iterative process: when I then had to set the montor brightness in the last step of comp. color temp such that I could see the darkest two squares, it messed-up the earlier steps of matching the various dither-to-solid patterns, which in turn then messed-up the shadow contrast again, so I had to go back repeatedly and readjust everything because my constraint was setting the monitor brightness out-of-order as the last step.

I ended up with the brightness nearly wide open! But it's all working now.

[mikemeister_admin]

Man, I really hate having to have my monitor so bright!
It's uncomfortable; almost hurts my eyes.
Probably will reduce the life of the monitor, too.

Maybe the near wide-open brightness necessary to see the leftmost
two darkest squares at 6500 means my monitor is too old.

Oh, well. ...

[-default]

If you're having to crank up the brightness to that extent, then I agree it's not acceptable, and for the time being you may just toss a little shadow detail.

Normally monitors have a separate adjustment for contrast and brightness.  Brightness is used to adjust the black areas, and contrast is used to adjust the light squares. Some of the newer LCD monitors, including my notebook's LCD, do not have a separate brightness adjustment, and this may be the case with yours. 

While it is possible to lighten the shadows using contrast, this amounts to the tail wagging the dog.  Contrast has much more effect on the brighter areas than the darker areas of the image.

Try looking at the advanced properties of your display (right click on the desktop, select Properties, click on the Settings tab, then the Advanced button).  You may find a separate adjustment for the brightness buried in the driver settings there.

I realize this may be at odds with your monitor calibration procedure and software, but perhaps you can apply a slight change before or after the procedure is complete.

Mike

[mikemeister_admin]

Yes, I used my monitor's brightness control for the shadow setting in my Mac OS X Tiger Display Calibrator. (And I followed the instructions to crank the contrast wide open.)

Since I have a CRT and not an LCD, I was able to use the Brightness & Contrast controls separately. And I was using the monitor's hardware analog controls, so I wasn't eating into my video card's 256 levels.

I'm pretty sure that the latter is the culprit: the Gamma 2.2 somewhat, but mostly the compensated color temperature setting of 6500 degrees, are reducing the shadow contrast by killing some of my 256 levels (probably mostly in the blue) in my video card.