M42... should have been M33

[MercianDabbler]

So ClearOutside told me I had hours of clear skies last night.

Set up the SP102, polar aligned, got the Canon 70D clamped at prime focus and focussed using my brand new paper cutout Bahtinov mask and then... the clouds rolled in.

Decided to try to wait out the clouds by pointing at M42 instead although it hadn't really dragged itself properly out of my local light pollution.

Managed about 11 usable light frames (15s at ISO 3200) before the clouds rolled across that part of the sky. Took some darks. Waited... waited... gave up. Naturally by bed time the sky was completely clear.

So here is my err... 'M33'. Stacked with DSS, exported to 32 bit TIFF and then adjusted with GIMP - fairly low intervention using curves and levels, pushed the saturation up and sharpened a bit. No mucking around with background level subtraction, lasso selections etc. Haven't even cropped it.

Biggest issue is the blue haloes around the stars. Is this CA or focus? The smaller ones seem fairly sharp with a tiny bit of trailing so I guess CA? Seems like a lot though.

[Stargazer33]

56 minutes ago, MercianDabbler said:

Set up the SP102, polar aligned, got the Canon 70D clamped at prime focus and focussed using my brand new paper cutout Bahtinov mask and then... the clouds rolled in.

Waited... waited... gave up. Naturally by bed time the sky was completely clear.

Been there, done that,  bought the T-shirt. More times than I'd care to think about! 

[michael8554]

I NEVER spend a night imaging without first taking an exposure at max ISO (12800 or 2560 for the 70D).

30 secs to 1 minute is usually enough, doesn't matter if the stars trail so long as you have something recognisable.

Quite apart from taking the wrong target, it confirms the framing is correct.

Michael

[MercianDabbler]

8 hours ago, michael8554 said:

I NEVER spend a night imaging without first taking an exposure at max ISO (12800 or 2560 for the 70D).

30 secs to 1 minute is usually enough, doesn't matter if the stars trail so long as you have something recognisable.

Quite apart from taking the wrong target, it confirms the framing is correct.

I think 30 seconds is the max that the camera will do without outside assistance. I should probably figure out how to do longer exposures using WiFi from the tablet but so far I've been getting by with less than 30 seconds.