M45 from Crago

[multiweb (Marc)]

This is a mosaic of two frames taken Saturday night last week. The object doesn't quite fit my field.
approx. 15x600s calibrated Flat field + Bias in CCD Stack. QHY8 - G11 - 5" celestron - autoguided PHP/ED80. Gain:1 Offset:60. Baader UHC-S + MPCC.

I was a bit dissapointed given the total integration time. I was expecting more. Clouds and sky glow, haze did a bang up job. Bit hard to process the gradients. Definitely will give it another go under much darker skies and better conditions as it was a bit low on the horizon.

Also got a lot of dark streak and noise due to fairly warm night and what I believe may be due to fast read out on the QHY8 camera. I'll try again with slower download speed. Never had the problem before. Might be temperature related.

Full frames available at:
http://www.multiweb.com.au/astro/M45.jpg [986KB]
http://www.multiweb.com.au/astro/M45_l.jpg [7.31MB]

Comments/Tips most welcome.

[Jen]

great pic M42 is my fav thanks for sharing

[gregbradley]

Nice image.

Those lines are unusual. Did you take flats?

Greg.

[Craig_L]

Looks pretty good to me but take Greg's point about the horizontal dark lines. Wish I had a view of M45 from my backyard.

[multiweb (Marc)]

Originally Posted by gregbradley

Nice image.

Those lines are unusual. Did you take flats?

Greg.

Yep. sure did. and I also calibrated the pictures. I got unusual patterns in my bias frames too that night. It's the first time I shot in relatively "warm" weather so for now I put that down to the temperature difference and the high speed downloads of the subs from the camera to the laptop USB. But I'll double check when those clouds go away Also sky glow and slight haze didn't help. M45 doesn't rise that high either. Anyway as they say "live and learn" . I think this is more of a dark site target like M31.

[multiweb (Marc)]

Originally Posted by Jen

great pic M42 is my fav thanks for sharing

Thanks Jen. It's one of my favourites too I saw some great pictures of it on these forums.