32 minute M27

[FaB-Bo-Peep]

Hi everyone,

The attached image is the result of just 32 mins worth of RAW subs captured from my severely light polluted back garden, stacked in Deep Sky Stacker, (with darks but no flats), and processed in StarTools and Paint Shop Pro, (I really have no idea of what I am doing though).

Scope is a Skywatcher 250PDS and camera is a Canon Rebel XS, (1000D).

In terms of my processing in StarTools I'm not sure my technique is any better than last years attempt but one thing that is obvious is that even though my subs were longer this year, (75 secs), the stars are rounder and that is thanks to the fact that I am now guiding using a ZWO ASI 120MC camera attached to my Skywatcher finderscope.

My next purchase is going to be a CLS filter as to say the light pollution in my back garden is bad would be an understatement!

Edited June 26, 2020 by FaB-Bo-Peep

[Paul M]

That's very nice. I'd be rather pleased with that

I have a 250 PDS and a 1200D, I haven't tried for M27 yet but I doubt I'd get that (in my limited experience) without flats. I've never bothered with darks. So just to confirm this was darks but no flats?

 

[tooth_dr]

Thats fab.  Have the same scope and also used it with a 1000d, never got as good an image as that.

Edited June 26, 2020 by tooth_dr

[FaB-Bo-Peep]

1 hour ago, Paul M said:

That's very nice. I'd be rather pleased with that

I have a 250 PDS and a 1200D, I haven't tried for M27 yet but I doubt I'd get that (in my limited experience) without flats. I've never bothered with darks. So just to confirm this was darks but no flats?

 

Thanks and correct, darks but no flats. At the end of the imaging session I just put the cap on the end of the telescope and take 8 - 10 exposures of the same length as I've been imaging at then load the light and dark frames into Deep Sky Stacker.  I've yet to do flats as I have no suitable white shirt to stretch over the end of the scope but really must do so soon as I'm sure they will significantly help. It's my understanding that darks help with hot / dead pixels and flats help with abnormalities in the imaging chain such as vignetting.

The 250PDS is hard work at times because of it's size but it's ability to grab so much light in such a shot time perfectly suits my bang for buck approach to astro photography 🙂

You should give M27 a go, it's a very nice looking object and is fairly large and bright which helps.

Edited June 26, 2020 by FaB-Bo-Peep

[FaB-Bo-Peep]

1 hour ago, tooth_dr said:

Thats fab.  Have the same scope and also used it with a 1000d, never got as good an image as that.

Stick at it, the scopes ability to grab light is significant and I'm constantly amazed that pleasing images can be achieved in such a shot time. Shout if you need any help, (but be warned I'm no expert).

[Paul M]

28 minutes ago, FaB-Bo-Peep said:

I have no suitable white shirt to stretch over the end of the scope

I used to worry about that but I don't think it's too critical. I just move the shirt between exposures to ensure variations get averaged out in creation of the master flat

Here is my advanced flats set-up  For devout kit-junkies, that is a Newbalance running top and the belt was from Aldi...

I don't do darks, my understanding is that there is some suggestion that with DSLR imaging they can increase overall thermal noise and potentially subtract from luminance data. Dithering beteween subs offsets any hot/dead pixels between frames that are then easily removed in stacking.

Without flats my images with the 1200D are trashed by dust bunnies and vignetting.

Anyway. I'm awaiting delivery of a ZWO ASI178MC camera and an ASI120mm guide camera, so my limited learning will start over!