Santa Barbara Instrument Group ST-i Operating Manual page 37

SBIG ST-i Manual
Enhancements
Images of galaxies tend to have a lot of dynamic range and you may find it
difficult to reveal the faint details in the arms without causing the core to
saturate. Try selecting the DDP instead of RGB in the "Method" drop down
box. Hit the Process button. DDP compresses the dynamic range of the
image. This may not look natural on all images but don't be afraid to try it.
An example is shown below.
RGB Processed DDP Processed
The initial color processing doesn't have to be difficult or complicated.
Once you have saved the original B&W image you can experiment over and
over with different settings until you achieve the results you like. Of course,
if you want more control over the image you may wish to process the R,G
and B frames separately and combine them just as you would if the three
frames were taken separately though RG and B filters as they are with
monochrome cameras. See below for more about extracting, processing
and combining RGB frames.
Easy Processing of Separate R,G and B Images
Monochrome cameras with filter wheels are used to make color images by
shooting separate red, green and blue frames through color filters. Separate
Red, Green and Blue frames may also be extracted from a Single Shot
Color Camera image for more control during the processing stages.
Advanced users may desire the additional control this gives them over the
color processing steps. CCDOPS also offers you the option to extract
individual color channels from the raw frame.
If you want to follow along with this example, a copy of the M33 raw
image is available on the SBIG software CD-ROM in the Images folder.
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