Last updated: 26 January 2007
Subject: Outline for Meade Image Processor Sent: Friday, January 26, 2007 10:58:19 From: Ted Rafferty (firstname.lastname@example.org) Below is an outline I use for post processing using the Meade Image Processor on frames from the Meade DSI-I that some of your reader might find useful. The Meade Image Processor is a pretty nice image processor, but the manual for it isn't very well written. I am still learning about image processing, so this outline should be viewed as a work-in-progress. Though it was written for the DSI-I, it should provide guidance for processing frames from other imagers. The steps that are particular to the Mead color imagers are the FITS3P frames. And the steps that are particular to the DSI-I are the ones involving the frame sizes. If the imager is monochromic, the R, G, and B frames will be created by separate exposures, and the steps following the "Split DSI Colors" would apply. Ted Rafferty Gaithersburg, Maryland ----------------- Post Processing using the Meade Image Processor on Frames from the Meade DSI-I Imager Rafferty 9/24/06 A. Taking Frames 1) Options: Color, High Gain, No Dark Applied 2) Saving Process: FITS3P, Save All Raw Images 3) Take a series of frames (6 or more) 4) Take a series of darks (at least 5) for the exposure time used B. First Stage of Post Processing 1) Copy raw frames and dark into a separate folder (you might need to go back to the original, unprocessed, frames). 2) Open Image Processor (AutoStar Suite > Image > Image Processor) 3) Separate the Darks by colors (Group > New (load group) > Group > Split DSI Colors) 4) Process each color groups (blue, green, and red) of the Darks separately. Load one color group of Darks (Group > New (load group)) and then combined them into a single image (Group > Combine (I use "average")). Save the combined dark image (File > Save Fits Image) giving it a name that indicates its color and exposure time. Repeat the steps for the other two color groups of the Darks. 5) Examine series for bad frames (Group > New (load group) > Examine). Step through the series to see if there are any frames badly trailed. If there are bad frames, delete them from the folder. 6) Separate frames by colors (Group > New (load group) > Group > Split Color) Process frames by one color at a time. You should see that the four new frames have been created for the darks and each of the original frames with an R, B, G, and L in their names to indicate which color group they are in. 7) Calibrate frames (Group > New (load one color group) > Calibrate (select the matching color dark and check "Include Dark Frame"). Flats can also be applied in this step if you have them (select the matching color flat and check "Include Flat Frame"). This will create a new frame for each frame with its name starting with "Calibrated_". 8) If you want to fix hot or cold pixels, apply a filter to the frames (such as the median filter), etc you should do them before the next step (i.e. before the frames are resized). 9) To improve the quality of the final results, change the size of the frames so they can be Drizzled. The dark and raw frames are 508 by 488 in size and you will want to resize "Calibrated" frames to 1295 by 976 (Group > Resample). This will create a new frame for each frame with its name starting with "HotFixed_Calibrated". 10) Repeat steps 6 and 8 for each of the colors except for L until you have sets of "HotFixed Calibrated" frames for the red, green, and blue. 11) Align all three colored frames using a two-star alignment (Group > Align > Two Star). The Align process will also combined the frames into a single image, but ignore it except to see that the alignment of all frames was successful. It is important to align all three colored frames to aid in a later step when creating a colored image. 12) Now you want to create three images from the three color sets of aligned frames. The aligned frames have names starting with "Aligned". Select a group of a single color and combined them (Group > New (load one color group) > Combine). I saw little difference between using average, median, or sum. 13) The combined image can now be enhanced using the Process Icons Toolbars displayed below the "File, View, etc" line. This step is worth experimenting with. And since it has a "Preview" option, it is easy to undo things that didn't work. The two I mostly use are the Image Convolution (selecting Normal or Smooth) and Image Prescale (Select Std Dev > OK for the first part and Preview the Linear and Log for the second part, you can do Log more than once to push the image. You might also want to try the "Histogram Equalization", which pushes the image.), once you have the image the way you want, select OK. Save the combined image as a BMP (File > Export Display as...) using a name that indicates which color it is. Since you will be merging the three color images together, what you do to one color image you should do the same to the others. 14) Repeat step 11 for each of the colors except for L until you have a single image for the red, green, and blue. 15) Combine the three colors together. First open the red frame (File > Open) and then do Color > RGB Merge... Select the name for the G and B frames. 16) Experiment with the color balance using the Preview option. You can adjust the color balance in this step and apply offsets to better align the three colors (though, since all the frames had been aligned to one another in step 9, applying offsets is likely not necessary). 17) Once you get the image the way you want save it (File > Export Display As..) and be sure to indicate that it is with all three colors. 18) To create a black and white version of the image, open the color image (File > Open) and, from the "BMP Image Plane Selection" select "Load as Mono". 19) Additional processing can be done on the black and white image that can not be done on the color image, including resizing the frame back to 648 by 488 and doing adjustments in Process. 20) Save black and white image (File > Export Display As..) and be sure to indicate what it is a black and white frame. If you want a 648 by 488 color image, you will need to resize the three 1296x976 color images to 648x488 before you merge them together (File > Open > Process > Resample).