NGC3184

[tich]

I went out to the dark site last night & decided to have a go on this target rather than the usual suspects & overall I'm fairly pleased with the result. The only downside is the vignetting so I'm looking for some plans for a light panel preferably one that works on 12v so I can fire them off at the darksite when I'm finished imaging. This is the best I can manage as if I stretch it any more it looks really horrible. Out of all the subs I deleted 5 which I didn't think was to bad one was due to a satellite & the others were due to tracking errors. I think I've managed to get some fainter galaxies in the background too which I'm quite pleased about.

NGC3184 is a spiral galaxy in the constellation of Ursa Major & is about 40 million light years away.

Taken using a 10" Newtonian Skywatcher 250P, Modified Canon 1000D & Baader MPCC on an NEQ6.

3 minute unguided subs at iso 800, 2 hours 9 minute & 43 seconds worth of data overall.
Stacked with 14 darks 12 bias in Deep sky stacker & finished off in Photoshop CS5.

[WaveSoarer]

That's a cracking image and very impressive for an unguided set of images.

[Xplode]

Looks pretty good

Those vignetting circles is pretty bad, but i wonder if they would dissapear if you posted your image somewhere it wasn't overcompressed like astrobin?

[tich]

Looks pretty good

Those vignetting circles is pretty bad, but i wonder if they would dissapear if you posted your image somewhere it wasn't overcompressed like astrobin?

The original Tiff file is showing them pretty bad too so I don't think posting an uncompressed image would make a lot of difference although this is a low res Jpeg version which does show them up a bit more. I just need to look round for some plans for a light panel so I can fire off some flats at the end of a session but it will have to run on 12v.

[Xplode]

Use your computer screen with white background. Not optimal, but should allow you to fix the vignetting in this image.

Skywatcher newtonian's have a small secondary mirror, you might want to consider changing it to a larger one.

Here's the vignetting on my GSO 8" f/5 newton with an enlarged secondary from originally 63mm to 70mm. Camera is a 6D full frame. I think Skywatcher use a 58mm secondary on their 10"

Vignetting on a crop camera is under 10% in the corners which is very good

[tich]

Use your computer screen with white background. Not optimal, but should allow you to fix the vignetting in this image.

Skywatcher newtonian's have a small secondary mirror, you might want to consider changing it to a larger one.

Here's the vignetting on my GSO 8" f/5 newton with an enlarged secondary from originally 63mm to 70mm. Camera is a 6D full frame. I think Skywatcher use a 58mm secondary on their 10"

Vignetting on a crop camera is under 10% in the corners which is very good

I'd use a laptop for making flats but unfortunately none of the laptops have a big enough screen to cover the aperture so I'm stuck. As set up & image at a dark site using the T shirt method isn't an option either so the only way for me is some sort of light panel.

[Xplode]

Have you tried taking flats during the day against the sky? even if focus isn't 100% the same they will probably still work. 

With flats for just vignetting it's not that important to have everything the same, only if you need flats to correct dust donuts it's absolutely crucial.