Embedded Files
What are we starting with?
I'm starting with 425 separate images collected over 6 nights in January 2025. They are from my remote imaging rig housed at Starfront Observatories in rural Texas. Starfront rents space to astrophotographers who would like to use their own equipment under extremely dark skies. I control the rig from home using remote desktop software.
The images are shot on a monochrome camera using 5 different filters: Luminance, Red, Green, Blue, and Hydrogen Alpha. The combined imaging time is 20h 35m.
Pre-processing Steps
Pre-processing Steps
After discarding any bad images, I load all of my image files into Pixinsight's Weighted Batch Preprocessing Script (WBPP). WBPP automatically performs all of the preprocessing steps.
Calibration and Cosmetic Correction remove imperfections from each image.
Subframe Weighting will sort the images by quality, so the best ones get more weight in the final image.
Star Alignment registers all of the images so the stars match in each.
Local Normalization matches the brightness level of each image to the best one of that filter.
Integration stacks (or combines) the light frames into master files that have an increased signal-to-noise ratio (see Astrophotography Basics).
Drizzle Integration- since this example is from my Redcat 51/ASI 294 MM Pro combo, the images are undersampled, meaning the pixels in the sensor are too big to capture small details, leading to poor star shapes. We'll use drizzle to fix that.
One image using Lum filter.
Final image after combining and processing everything.
The Calibration tab in WBPP, showing all of our Lights, Darks, and Flats. In this example I already have master darks and flats.
My settings for WBPP
Local Normalization- uncheck interactive mode
Image Integration- UNCHECK AUTOMATIC MODE and select Generalized Extreme Studentized Deviant as the rejection algorithm. It works extremely well.
Settings in the Lights tab.
The Post-Calibration tab showing all of the filters and their drizzle settings.
Under the Post-Calibration tab, I enable drizzle but not Fast Mode or Fast Integration. I haven't been happy with the results of the Fast modes.
1x or 2x drizzle will prevent star artifacts in undersampled data.
First: Drizzled, second: not drizzled. Notice the pointy stars on the right.
When WBPP is complete it produces 5 master files, one for each of the filters I used- Lum, Red, Green, Blue, and Halpha.
Next is Processing in Pixinsight
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