Because the fog is back and I want to finish this series I tried many tricks to get this image from only 5 Blue and 1 Hydrogen Alpha Sub.
I had one very good HA and a few Blues from right after sunset before the fog came in.
I made a "Red" by extracting the Stars from the HA then made a "Green" by forming the average of the "Blue" plus "Red".... Green is between them.
I then did a Photometric calibration of the stars and got the "right" colors.
I then processed the one HA in my normal workflow to get the HA added to the stars... now fully saturated. [Destarred HA denoised in PS with Topaz, stretched and greyscale stars added back; this image is then added to the Red channel (carefully) in PS.]
Anyway, I do enjoy mathematics.
From
GalaxyMap:This large faint HII region next to the Trifid nebula is ionised by the O9Ib supergiant LS 4551 and the O-class LS 4538, It lies in the direction of the supernova remnant SNR G006.4-00.1 W 28.GENERAL NOTE ON SHARPLESS2 OBJECTS>>>>>>>>>>>>>
There are 313 Sh2 objects. As of the date of this image I had imaged 282 (90%).
There are 12 too diffuse/large to image with my set up (Sh2 111, 117, 122, 131, 132, 145, 178, 218, 221, 230, 268 and 310). I may look for other images so I can get a complete collection or make my best shot for completeness.
There are 5 that are never above 14 DEG (Sh2 2-6) [Edit 7/12/21- I can get these now with pier upgrades and the images are completed as best as I can].
These remainder are in Expert Scheduler waiting for them to pass by.
The first one was taken on December 23, 2013.
Many were taken with my old Tak 180 ED, which had a wide field of view, but was replaced with my Stellarvue 130, which is more narrow field. I have also taken two very wide field HA images with my Nikon D800 and a 50mm lens.
This is my collection:
Sharpless2Wide-Angle Hydrogen Alpha Nikon Image Sh2 79-171Please note there is also a Sharpless2 Group with now more than 1500 examples.
Sharpless2 GroupOther useful links include:
Gary Imm's CollectionGalaxyMap's CollectionThe Sharpless CatalogThe MDW H-alpha Sky SurveyReiner Vogel's detailed observing catalogHope you enjoy these obscure but interesting objects...
Comments