Synecdochically
01-08-2018, 06:48 PM
231661
This is a 24 panel mosaic of the Milky Way core and the Rho Ophiuchi region. The full size image is around 380MP.
For a 50% downscaled (95MP) version, click here: https://drive.google.com/open?id=1yzGdqimwOvEP8oUZzcYcMxGxmY gG4gVk. Be aware it's a ~120MB dowload.
I took this from somewhere between Stanthorpe and Texas, QLD, in Bortle 1/2 skies with no moon.
Gear/software used is:
Nikon D5200
Tamron 70-200mm f/2.8 at 135mm f/4
Skywatcher NEQ6
BYN for imaging, Stellarium for pointing, EQMosaic for creating the mosaic pattern and AstroTortilla for platesolving
No guiding unfortunately (my setup for attaching the guide scope to the camera lens had too much flexure).
Each panel is made from the best 9 out of 11 shots, 50 seconds each at ISO1600.
216 shots total, for 3 hours of exposure time.
40 darks, 40 flats.
Processing:
This image was a real challenge to process. I wanted to make the mosaic in Pixinsight so as to not lose quality by going to TIFFs and using Microsoft ICE or the like. In the end I settled on something like this processing method because I was having lots of issues with stitching artefacts. Most everything was done in Pixinsight.
Calibrate & integrate frames (without normalization, because for some reason any normalization made some frames much brighter than others - luckily the lack of normalization wasn't a huge issue because the skies were so dark).
Auto-stretch each integrated frame individually, and apply that stretch to the frame's histogram.
Register the frames relative to each other using MosaicByCoordinates (with distortion correction).
Merge the frames using GradientMergeMosaic.
Apply DBE
Apply SCNR
Various curves transformations (S-curves, adjusting saturation, adjusting colours slightly)
Local Histogram Equalization
Range mask to isolate background
Further curves transformations
Finally I exported to TIFF (although I couldn't export the 380MP version as a 16 bit TIFF, so I downscaled by 50% for this step) and then did further rescaling and a bit of sharpening in Photoshop.
I didn't process this in the most scientific way, but I think it came out looking fairly nice, so I hope you enjoy.
This is a 24 panel mosaic of the Milky Way core and the Rho Ophiuchi region. The full size image is around 380MP.
For a 50% downscaled (95MP) version, click here: https://drive.google.com/open?id=1yzGdqimwOvEP8oUZzcYcMxGxmY gG4gVk. Be aware it's a ~120MB dowload.
I took this from somewhere between Stanthorpe and Texas, QLD, in Bortle 1/2 skies with no moon.
Gear/software used is:
Nikon D5200
Tamron 70-200mm f/2.8 at 135mm f/4
Skywatcher NEQ6
BYN for imaging, Stellarium for pointing, EQMosaic for creating the mosaic pattern and AstroTortilla for platesolving
No guiding unfortunately (my setup for attaching the guide scope to the camera lens had too much flexure).
Each panel is made from the best 9 out of 11 shots, 50 seconds each at ISO1600.
216 shots total, for 3 hours of exposure time.
40 darks, 40 flats.
Processing:
This image was a real challenge to process. I wanted to make the mosaic in Pixinsight so as to not lose quality by going to TIFFs and using Microsoft ICE or the like. In the end I settled on something like this processing method because I was having lots of issues with stitching artefacts. Most everything was done in Pixinsight.
Calibrate & integrate frames (without normalization, because for some reason any normalization made some frames much brighter than others - luckily the lack of normalization wasn't a huge issue because the skies were so dark).
Auto-stretch each integrated frame individually, and apply that stretch to the frame's histogram.
Register the frames relative to each other using MosaicByCoordinates (with distortion correction).
Merge the frames using GradientMergeMosaic.
Apply DBE
Apply SCNR
Various curves transformations (S-curves, adjusting saturation, adjusting colours slightly)
Local Histogram Equalization
Range mask to isolate background
Further curves transformations
Finally I exported to TIFF (although I couldn't export the 380MP version as a 16 bit TIFF, so I downscaled by 50% for this step) and then did further rescaling and a bit of sharpening in Photoshop.
I didn't process this in the most scientific way, but I think it came out looking fairly nice, so I hope you enjoy.