Download the file RGB.py, image_scale.py and place them in the same folder as your fits files. Then, please run the RGB.py and type the answers. The output will be a color image file in png format (e.g:https://github.com/tremou/RGB_MSUastro/blob/master/M57_RGB.png)
#################################### Example Usage: ####################################
python RGB.py; Object Name: M57; R filter filename:R_m57.fit; B filter filename:B_m57.fit; V filter filename:V_m57.fit
#################################### -->output: M57_RGB.png ############################
The script "RGB.py" is an interactive python script that creates color images using three images from different filters (usually R=red, V=visual and B=blue for MSU data). This version is mainly based on the tips are given in Astrobetter (http://www.astrobetter.com/blog/2010/10/22/making-rgb-images-from-fits-files-with-pythonmatplotlib/).
Image scale can be adjusted by using the "img_scale.py" which is written by from Min-Su Shin (http://www.astrobetter.com/wiki/tiki-index.php?page=RGB+Images+with+matplotlib). The img_scale script should be at the same folder as the main "RGB.py" script.