M101-the Pinwheel galaxy-DSLR

[ONIKKINEN]

245x60s of exposure

Taken with an OOUK VX8 on a Skywatcher EQM-35PRO and a Canon EOS 550D. Guided with a 60mm F4 guidescope and an ASI 120mm, controlled by a WIN10 minipc remote controlled with a tablet. Guiding was not great, hence the 50% resize. I think the RMS was somewhere around 1.5-2.5 most of the time. Bortle rating of somewhere around 6-7.

This is old data that i have been sitting on since late april when this was captured, i have been processing it every now and then but never thought that its "finished" yet. I think this one looks pretty good. I took around 7 hours of 60s subs on M101 during three nights just before the spring season ended, this shot consists of 245 one minute subs as most of them are ruined beyond use, or just good enough to stack but will produce extra noise. This was my 4th actual DSO imaging target with a GO-TO mount so definitely a work in progress.

 

Problems that are difficult to fix now but easy to avoid later would be to take proper flats in situ and not later. Slight changes in camera angles ruined some of the flats and led to unnecessary gradients. I think i also collimated the scope and still used the same flats afterwards, which obviously in hindsight is not a very good idea.

 

Processing in SIRIL and photoshop. Nothing fancy in PS, some masked saturation adjustments, lightroom tweaks and denoising in topaz.

[russ]

That's a really nice image

[teoria_del_big_bang]

I agree that is an excellent image

Steve

[ONIKKINEN]

Thank you very much!

On another thought, i wonder what the faint small fuzzies are dotted around the picture. Stellarium is not very helpful and the platesolve function in SIRIL did not annotate them.

[teoria_del_big_bang]

14 minutes ago, ONIKKINEN said:

Thank you very much!

On another thought, i wonder what the faint small fuzzies are dotted around the picture. Stellarium is not very helpful and the platesolve function in SIRIL did not annotate them.

You can upload your image HERE to find out.

Steve

[teoria_del_big_bang]

Here you go:

Steve

[Sunshine]

Great image!

[ONIKKINEN]

I followed the astrometry.net pathwway down the rabbithole and found lots of interesting faint fuzzies! https://www.legacysurvey.org/viewer/?ra=210.8357&dec=54.3581&layer=unwise-neo6&poly=209.4818,54.0860,211.8538,53.7734,212.2074,54.6149,209.7887,54.9339,209.4818,54.0860

 

Some have redshifts greater than Z=0.1 which places them somewhere in the 1-2 billion lightyear range! Not much more than single pixels of course but i almost cannot believe an 11 year old DSLR can capture any pixels of something like this...

[Adreneline]

1 hour ago, ONIKKINEN said:

245x60s of exposure

An amazing result - your image has a real sense of three dimensional depth to the galaxy. All too often images of M101 - including my own! - appear quite two dimesional and flat.

Adrian

[ONIKKINEN]

3 hours ago, Adreneline said:

An amazing result - your image has a real sense of three dimensional depth to the galaxy. All too often images of M101 - including my own! - appear quite two dimesional and flat.

Adrian

Im happy you like it!

Not sure i understand the 3D-aspect fully, but from the failed versions of the same data set i have processed i think i can sort of get what you mean. Its very easy to "deep fry" an image of M101 with light pollution in the mix and getting the right mix of even background and the faintest spiral structures took too many tries for me. At least the lower part of the spiral was very easy to process out when trying to "fix" other parts of the image.

[Lee_P]

Great result. good job

 

[Rodd]

Very natural looking.  Like I am peering through the worlds best binoculars. 

[irtuk]

Great Image, Check your PM's. I am curious to know whether we worked together in Helsinki a few years back.

Ed.