Jayanne English's Astronomy Image Making Information

Calibrate your monitor.

1. Find yourself a CRT. LCD monitors in general cannot be colour balanced sufficiently for creating images that will look good on a number of monitors.


2. Download the following calibration images:
   • Gamma chart (Gamma_black_new.png)
   • Gamma chart and skin tones
   • David Malin's greyscale (malingreyscale.jpg)
     (There is more information on calibration at Malin's website)
   
   
3. Turn off the flourescent lights. Some daylight is o.k.
   
   
4. Let your monitor warm up.
   Some monitors let you do an "image restoration". If so, ensure you do this, after the monitor warms up.


5. Settings for your monitor:
   These are the values you are aiming for. Brightness and contrast are set using hardware buttons on the monitor. The others are now usually set in software.
   • White point: 6500K
   • Brightness 55%
   • Contrast 100%
   • Gamma 2.2


6. Calibrate your monitor:
   • Mac Platform:
     You can run your monitor from your Mac laptop using a display connector. Open the System Preferences and then open Displays -> Color -> Calibrate. This will give you a wizard for calibrating your monitor.
   • Linux Platform:
     Use the "xgamma -value" command (in the command line) to set your gamma by hand using an image manipulation package such as GIMP and the calibration images above. Detailed instructions are in calibmonitorlinux.txt.
   
   
7. Check the calibration using the calibration images above, particularly David Malin's Greyscale.
   Make sure the grey's are neutral (e.g. not bluish-grey), that there are distinctions between each grey level, that the flesh tones look convincing and that the primary colours are pure.


8. Compare images that you create on your monitor with how they appear on other monitors. For example reset an LCD to a factory default and see that your images look acceptable on those.