Help With Gamma Setting

[Garris]

I have been editing my photos for a long time noticing that there is no shadow detail and assumed this to be caused by poor dynamic range in CRT monitors. I now have discovered that my gamma and black level are not right. Using Norman Koren's gamma / black point chart @ normankoren.com and following instructions for adjusting both using "Adobe Gamma" and Brightness control on monitor, I find that I can not see the low key tones unless I decrease Gamma (slider to the right) to 1.5 even with brightness full up. I simply can not achieve the 2.2 Gamma setting and still be able to see the bars which are used to set brightness. When viewing a step wedge the entire lower quarter is black. This has been so since the monitor was new. It is 5 years old now. Is the monitor defective? "Windows"and internet pictures look fine at gamma 2.2 but at 1.5 everything is washed out but I can see the quarter tones. I'm horrified at the thought that I have compensated for this problem on all my photos using curves and that when I correct this problem they will have little contrast. Any help desperately appreciated!

[alrobin]

Garris,

This demonstrates the importance of constantly checking your scanner/monitor/printer/projector system to ensure that each is calibrated correctly and that they all work together as a compatible system.

However, if you still have the original images (raw, tiffs, original jpegs, etc.), then you are still ok and they can be re-edited. If not, well - as you said, you may be out of contrast.

[Garris]

Very true words Al but what I really need to do is figure out why I can not get proper calibration. I guess its either the monitor or my video card. Both are 5 years old however I have had this problem since new. Thanks for the reply.

[Ken Cox]

Garris

try this

http://www.eye4u.com/home/

select special

select monitor set up

ken

[alrobin]

Garris,

You should be able to calibrate both.

For the monitor, you may be able to activate an Adobe "gamma" correction in the Control panel.

For some video cards, you can also go into the advanced settings and change the value for each of the three RGB colours. I had to make changes to these in my laptop so that the projected colour values were more "natural".

[Garris]

Ken, I used your link and was presented with a step wedge. 80 through 100 are all black. This is my very problem. Brightness is at max and turning contrast down only worsens things. This is other than a simple brightness/contrast issue. I have been adjusting adobe gamma in control panel yet can not find a point where gamma is 2.2 (which is the "windows" standard) and still see the lower tones. In Adobe Gamma it says to adjust brightness till the small black box is very dark (but not black) while keeping the white box white. All I ever saw was the larger black box and did not realize there was a second smaller black box because this box is a very low tone ( maybe 20 or 40 in the 0-255 tone range). I would be interested to hear how many levels you guys can see on a 21 step wedge begining with white. You can download the wedge from normankoren.com. It is under the "monitor calibration and gamma" link and there will link to a file named:Printer test File.jpg.zip. The graphic contains other elements for calibrating color but that is not a problem. maybe we are all missing some tones. Thanks for the interest.

[Ken Cox]

Garris

found another link for you

http://www.astropix.com/HTML/J_DIGIT/TOC_DIG.HTM

ken