Grainy M51 Short Shot

This is M51 and NGC5195. It’s grainy because it’s only 8 shots. 75 second exposures at ISO 800 through the William Optics z61 so 360mm, f/5.

I’ve cropped it to be similar in size to a shot i did through the takumar lens around this time last year. The Takumar shot (below) is a single exposure because i hadn’t discovered siril yet.


Shaving the Yak

Generally crap results last night but I did make some basic progress.

  • I can reliably connect to the mount from windows with a batch script that deletes the connection and restablishes it
  • I can set the camera to taking small-ish jpegs for doing the polar alignment then have backyardeos switch to high-res for imaging
  • I can use a filter ring to stop the Takumar 200mm lens down to 37mm which is about f/5.6. This seems to reduce, if not eliminate the severe chromatic aberration i was seeing with it.
  • From my side-yard I have a smallish slice of unobstructed sky but i have a good view of Polaris and the Zenith.

Aside from that it was a sh*tshow with false starts and loose clutches stopping me doing any real imaging. Wednesday night is supposed to be clear and i’ll try to do my prep in advance and get a solid couple of hours outdoors.

A Messier Evening

M51 and NGC5195

M51 is the whirlpool Galaxy. 23 MILLION light years away! It’s much prettier than my sad blur above but i’m delighted to have found and photographed it. The smaller blur on the left is NGC5195.

I took a number of exposures at 180 seconds, f/8, ISO 800 with a Takumar 200mm lens. I tried combining them with DeepSkyStacker but didn’t see any improvement. The image seems quite noisy and the stars are artifacted so if i’m out tonight i’ll try f/4 ISO 400 and maybe 240 seconds. I’ll also try 60 seconds.

This much better image is from Wikipedia