M45
image processing (no
tutorial)
To produce pleasing astro images many things have to come together. Sharp focus, guiding, lots of data (exposure time), darks and flats. Not to mention weather, seeing and light pollution? Many of my images have one or more shortcommings. But I'm learning all the time and when I make progress it is like a small victory. Image processing is one area where I like to think I made some progress. Below are three representations of the same 12 minute exposure data on M45. These pictures give an idea of what can be done with careful processing to get the most out of the available data. ________________________________________________________________
|
|
M45 Pleiades, 17 November 2007 Scope: William
optics 90 APO @ F6.9 _________________________________________________________________________ |
|
 |
This is a single raw frame. This what light pollution does to only 80 seconds of unfiltered exposure. Ten exposures where stacked. Initially with Registax and later again with Deepsky Stacker. No darks, Flats or Bias frames. |
 |
This was first result after initial color processing in november 2007. I was happy then and judged the result to be good enough to publish. But honestly: the processing was greatly overdone and M45 didn't not look natural. |
 |
Result after re-processing the image with more carefully applied curves and levels and more attention to natural appearance |
 |
The final image. This is (IMHO) a more balanced result after re-processing the image using the Zone System Method . This method is based on controlled stretching of dim parts (zones) and compressing the bright parts of the image. It works realy well. |
Astrophotography
by Maarten Labadie (c) 2003