Yet one more 127 Mak M27

[JamesF]

I thought this might be my last attempt on this particular target for the time being, but thanks to the Moon it's rather washed out and the outer areas of the nebula are quite hard to separate from the sky. In fact it's been rather a pig to process. In particular to keep the outer nebulosity I've had to compromise and leave the sky rather noisy. I therefore intend at least one more visit this season, weather permitting.

In fact it was mostly a test of my guiding setup. My previous image (which I actually think is better) used unguided 45 second subs and I had to throw a few away because of trailing. For this I was guiding my 1500mm focal length Mak with a finder-guider and QHY5L-II guide camera. I couldn't get AA5 to play, but PHD would and I was managing 90 second subs. They're not perfect, but they're not that far off, and if I can get the mount better polar aligned it should give the guiding an easier job. The stars towards the bottom right look a little stretched whereas the ones to the top left seem better, so I wonder if that's actually more of an optical problem then a mechanical one. Anyhow, this is two hours total of 90 second RGB subs (I was going for a few more but the cloud rolled in at just after 3am), cropped but not resized.

The keen-eyed will notice that the variable star on near the centre of the bottom edge is still showing quite red compared with its (visual neighbour). I deliberately kept that in the cropped version

James

[Stargazer33]

That's really nice James. I like the variation in star colour. Mine always seem to end up the same colour - white.

[JamesF]

That's really nice James. I like the variation in star colour. Mine always seem to end up the same colour - white.

There's no luminance in this image, which people (Olly and Francis at least, as far as I recall) have told me can wash out star colours. Otherwise I'm really not sure what I've done to achieve such a range of colours in the stars. I certainly couldn't claim any intentional skill on my part I have wondered if it isn't something that happens as a result of using quite a slow scope, but Jake's M27 posted earlier today also shows a wide range of star colour at f/4.5 so that can't be it.

James

[fwm891]

Coming on James - not tried any dso's with my 127 - must give it a go...

[JamesF]

Coming on James - not tried any dso's with my 127 - must give it a go...

Should be very interesting to try with the Avalon mount. I like the image scale it gives on planetary nebulae and globs, but the guiding and imaging time are more of a challenge. It's nice to think that such images can be produced with what might generally be considered something of an "entry level" scope, too.

James

[andyo]

a very nice capture