The first time I did this was 22h with a CCD and my Tak 180ED (F2.8) and the results were at best "subtle". This has a reputation for being dim.
Here I destarred the denoised the Ha and O-III then used GHS setting the symmetry point in the center on the dull areas of Sh2 94.
I then added the two with the usual HOO recipes and added the RGB stars in Photoshop. I denoised on more time the destarred image before adding the stars back.
Total exposure 5h with the CMOS at F 6.9 and GHS. Here is 22h with the CCD at F 2.8.
Sh2 94 H-alpha O-III RGB GHS Forum DiscussionNarrowband technique used for each channelFrom GalaxyMap:Sh 2-91, Sh 2-94 and Sh 2-96 are all filaments of the supernova remnant
SNR 065.2+05.7, which has a diameter of about 70 parsecs and an age of about 20 thousand years.The full extent of the supernova remnant can be seen in the visual frequency images in a 2004 paper. [
1]
A small radio ridge of the SNR G 65.2+5.7 coincides with the small but bright filament S94.[
2]
The supernova remnant G 65.3+5.7 is located at a distance of 900 - 1000 pc but is described separately from Sh 2-94 = LBN 064.90+06.74 .[
3]
GENERAL NOTE ON SHARPLESS2 OBJECTS>>>>>>>>>>>>>There are 313 Sh2 objects. All now imaged.
This is my collection:
Sharpless2Wide-Angle Hydrogen Alpha Nikon Image Sh2 79-171Please note there is also a Sharpless2 Group with now more than 2600 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...
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