NGC 3359, a barred spiral galaxy in Ursa Major

[tomato]

This is just over 5 hrs integration on the Esprit 150/ASI 178 dual rig comprising:

77x2 mins Lum

37 x 2 mins R

18 x 2 mins G

24 x 2 mins B

Mindful of the perils of oversampling, these were all binned 3x3 so imaging at 1.41 arcsec/pixel.

 There was something strange going on with the seeing last night, I was getting good HFRs at the start but as the object climbed higher in the sky the numbers tailed off and the stars were visually poorer on the subs. Repeated re focus attempts would not improve them, but I did notice some variation in the guide star quality in PHD, so maybe there was some high cloud coming through later on that I couldn’t pick up visually. With high pressure in control I wouldn't think it was atmospheric turbulence, but there was a gusty wind last night in Shropshire.

 At this point I’m not sure if binning 3x3 is the way to go on my rig, I have had to move away from my usual processing procedure to prevent a very ‘blocky’ result. Not too keen on the blue/green stars either.

[vlaiv]

36 minutes ago, tomato said:

At this point I’m not sure if binning 3x3 is the way to go on my rig, I have had to move away from my usual processing procedure to prevent a very ‘blocky’ result. Not too keen on the blue/green stars either.

Did you bin in software?

You can always process data unbinned to see if you'll get better result.

Do you know what sort of FWHM you have in the image?

[tomato]

1 hour ago, vlaiv said:

Did you bin in software?

You can always process data unbinned to see if you'll get better result.

Do you know what sort of FWHM you have in the image?

Hi Vlaiv,

No I binned at the image capture stage, I usually hardware bin 2x2 on this set up as these are mono cameras and imaging at 0.47 arcsec/pixel would be very optimistic, but you are quite correct, software binning would give me maximum flexibility at the processing stage.

APP reports that the combined LRGB image has a FWHM min of 2.39 and a max of 2.50.

It's looking clear here again tonight, so I will have another session on this galaxy at 2x2.

[Tomatobro]

It will be interesting to see what happens when you add in my data

Lum 60 x 120 seconds

red 20 x 120 seconds

green 20 x 120 seconds

blue 20 x 120 seconds

Ha 20 x 120 seconds

10 inch RC using a ZWO 1600mm all binned 3x3

Edited February 27, 2022 by Tomatobro
info added