M31 & M33 08/12/2022

[imakebeer]

Out again last night, great to have had two clear (albeit very cold!) nights in a row 😁 Any tips you guys can share are welcome.

Yesterday I posted some images of M31 but a flat battery meant I wasn't able to take any dark frames - so the first thing was to put that right. I stuck with my trusty Nikon D5500 this time + SW150PDS + HEQ5.

60 x 15s lights at ISO 800, plus 10 darks, stacked in Sequator and tweaked in GIMP.

I'm really pleased with this as I've only been at this a few weeks - most of which were cloudy, so go figure! I think the addition of some dark frames have improved it. Compared to the previous night's effort linked above I think the dust lanes are sharper.

Nevertheless I can't help but wondering what is the difference between this and the amazing images I see on the forum? Is it the equipment? Is it at capture, many more light frames needed, different exposure or ISO? Or Stacking? Or processing in GIMP? Or all four? One criticism of my own images is when you look closely they all look very grainy (=noisy? You can see the individual RGB pixels I think. But I don't know the source or reason for this)

Anyway, here's the pic:

 

It was getting late but I figured while I was out with the scope pointing in roughly the right place I'd have a quick crack at M33 Triangulum Galaxy. Still D5500 but this one is only 30 x 15s lights at ISO 1000, plus 10 darks. This one is not so good but it's a start and something I can work on - the galaxy is just about discernable and it looks like a decent pic would show the swirling spiral arms, right?. I was pleased at least that I'm getting the hang of the HEQ5 that I was able to make it slew to an invisible target! 😂

[Sarek]

Very nice pictures. Like you, I'm a complete beginner. We have similiar kit though.   

Did you think to add flats and bias shots? The former can, I'm told, last for several months

Perhaps you could try for longer exposures? I tried 45 seconds last night and feel confident enough to try up to 2 minutes next time.  Remains to be seen what difference that will make

Edited December 9, 2022 by Sarek

[Paul M]

4 hours ago, imakebeer said:

I can't help but wondering what is the difference between this and the amazing images I see on the forum? Is it the equipment? Is it at capture, many more light frames needed, different exposure or ISO? Or Stacking? Or processing in GIMP? Or all four?

A bit of all four and maybe some stuff you don't yet know that you don't know!

Don't worry you are doing fine. Perhaps the true fun in astrophotography is the never ending journey to satisfaction. When you look at the amazing images posted on these forums you'll find the owners picking holes in them, wondering how to improve some imperceptible blemish or artifact. Beauty is in the eye of the beholder...

I cheat. I don't do grand vistas of well known nebulae. I'm interested in asteroid tracks and fuzzies that take up 2 pixels on an 8 megapixel image!  

[imakebeer]

2 hours ago, Sarek said:

Very nice pictures. Like you, I'm a complete beginner. We have similiar kit though.   

Did you think to add flats and bias shots? The former can, I'm told, last for several months

Perhaps you could try for longer exposures? I tried 45 seconds last night and feel confident enough to try up to 2 minutes next time.  Remains to be seen what difference that will make

I did actually take bias shots but haven't done any flats yet. In a cruel ironic twist, Sequator doesn't give the option to use bias, though it can use flats! But it is really quick and user friendly! @Rallemikken was telling me I should really move on to DSS/Siril for more control, which I'll do, it's just one step at a time.

I've done some 60s lights before (the previous night!) which worked OK - to some extent I was being lazy with these ones as I didn't get outdoors until later so I did more lights at shorter exposure times (15s). I did 1-2 test frames at 120s but got star trailing - I think the mount is already fairly well aligned but maybe I need to make it even better. I do actually have a guide scope and camera in boxes but haven't yet got to the point of setting them up yet - perhaps that's the final key to enable really long (i.e. 120s+) exposures???

2 hours ago, Paul M said:

A bit of all four and maybe some stuff you don't yet know that you don't know!

That's a bloomin' good point right there - there are some things I know I don't know, but frankly I've no idea what else I don't know! 😱😂