Beautiful spiral galaxy Messier 74 (also known as NGC 628) lies some 32 million light-years away toward the constellation Pisces. An island universe of about 100 billion stars with two prominent spiral arms, M74 has long been admired by astronomers as a perfect example of a grand-design spiral galaxy. (Write up by NASA)
When I was processing my 30hrs Lum data at the end of Oct, I was so confused about the suddenly showed up of strip-shape dust after DBE process. At the very moment, I believed it was some bad result of my incorrect DBE, cos I never heard of the existence of IFN around M74 . However, when I did a search on Astrobin later, and found that there was only 1 AB user posted something similar.
Bart Delsaert posted his perfect pic
Deep Messier 74 and IFNtaken with 16'' Dream @F3.75 on March 2023. Thanks to a super fast focal ratio of 3.75 and 10hrs of integration time, those IFN (or dust) can hardly be ignored and the M74 is surrounded by those dust in the middle. And, if you download Bart's work and extract his Lum channel with a little pop-up in Camera Raw, you may find many similarity between his and mine, all of which convinced me that these strip shape of dust are really something there. (See area from ①to④)
My work of M74 contains a total exposure of 61.5 hours including 50 hrs of Lum data captured between Oct 16 to Nov 14 with my WO
[email protected], (not yet collimated). Besides, 10 hrs of RGB and 1.5hrs for Ha data contribute to color info of M74.
Comparing with the Lum of 30hrs ver, IFN on the right part can be stretched from the background with less struggle, whileIFN on the left side suffers from weird light pollution so no IFN can be recognized.
The IFN around M74 are so dim that 50hrs @F6.4 simply not enough. To have better SNR, approx 200 to 300 hours exposure (or equivalent amount with faster scope) may bring more pleasant results.
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