In a previous post I showed the result of combining multiple different exposure time images to form an HDR image using the PixInsight
GradientHDRComposition process. The resulting image lost much of the
Ha background which was presented earlier in an
Ha only image. So, I decided to try manually blending the different exposure time images with masks following a technique perfected and popularized by Jerry Lodriguess for Photoshop (I adapted it to PixInsight). It was a lot of work, but, in the end it was possible to bring out the
Ha background along with the nebula. Quite honestly I'm not sure I can reproduce the work flow because multiple attempts were required and, in the end, two different approaches were merged together. However, I really like the final result. Hope you enjoy it.
IMAGE DETAILS:
Equipment:
W.O. Star71 telescope,
EFW Filter Wheel (8-Position), 3 nm Chroma S/H/O filters, ASI1600MM camera (-15C, Gain=140), CEM40 mount, Orion MMAG autoguider, StarLite stepper motor (focusing), Dew Heaters
[Mount/ASI1600MM camera/Filter wheel/MMAG autoguider/Focusing stepper motor all controlled remotely using APT. APT is on a laptop in the house which is connected by a WEme 4-port USB 2.0 extender system with 40 ft ethernet cable to the equipment outside at the end of my mobile home driveway. The ethernet cable is fed into the house through a slightly open window where the screen has been temporarily set ajar.]
Images: (Dithering on every image)
Ha
Oiii:
Total Exposure: 8
hr 31.5 min
Master Dark Frame (24 Darks), Master Flats (30 Flats and 30 Flat Darks for each filter).
Software:
Captured with
APT, Guided with PHD2, Processed with PixInsight. The new
APT Autofocus routine was used for all focusing.
Thanks for looking,
Steve