Ngc4945

[Asterix2020 (Paul)]

As everyone in Brisbane knows, we got a lovely clear night last night. First real go with the new RC8. OAG hasn't arrived yet so guided with separate guidescope. Not sure if collimation or focus was spot on, stars seem a bit big? Only a slight crop to remove stacking artefacts. 13x 10 min subs, flats and darks applied.

Any advice appreciated.

Full res: http://www.astrobin.com/full/97889/0/

[Shiraz (Ray)]

impressive image Paul.
re stars - maybe they look slightly enlarged, but that could just be seeing. If you haven't already used it, deconvolution may help pull them together a bit. but it is still a really nice image.

[pmrid (Peter)]

Strewth Paul. That's a decent image. Did you tweak the collimating any more? And did you drift align?

Peter

[Asterix2020 (Paul)]

Originally Posted by Shiraz

impressive image Paul.
re stars - maybe they look slightly enlarged, but that could just be seeing. If you haven't already used it, deconvolution may help pull them together a bit. but it is still a really nice image.

Ray, I tried deconvolution in Startools but it didn't do much. Maybe I didn't set the mask and parameters up correctly. It did ring the brighter stars so I think it might have been my lack of skill in using it. Startools has a Magic module that shrinks stars that did help a bit.

[Asterix2020 (Paul)]

Originally Posted by pmrid

Strewth Paul. That's a decent image. Did you tweak the collimating any more? And did you drift align?

Peter

Peter, thanks!

No further tweaking that night, only what I did just after you helped my with the 4 corner focusing technique and out of focus technique. The seeing was bad that night so I wan't sure how close I got it, seeing was better Saturday night. I think I'll leave it as it until I get the Moonlite focuser and then tweak again if necessary. I've attached a full frame so you can see a little elongation in the corners.

I used Alignmaster, only got one iteration until it gave me no stars! Luckily it was pretty close, I setting it up on a star and it only moved slightly over 10 minutes so I thought I'd try my luck guiding. Balance may have been of because after this I aimed at the Virgo cluster and it couldn't guide/track correctly.

[Asterix2020 (Paul)]

Funny what you can find on images. About 1/3 of the way from the centre of NGC 4945 to the edge of frame towards 11 o'clock there is a small circular fuzz. The maps in Skytools (go down to mag 20) show a star there, so I thought it was some processing artefact. But it's on all the raws as well. Maybe I'd nabbed a faint comet! But it's visible on the DSS images of the area (Skytools is great as it can just download them and put them on the map). So not a comet I could not find it anywhere until I found this obscure reference: http://adsabs.harvard.edu/full/1964ApJ...139..899D

It just says it may be a dwarf companion. I thought it was a distant background galaxy. I can't find anymore information about it, but would love to know more about it if anyone knows how to find out more.

[astroron (Ron)]

Originally Posted by Asterix2020

Funny what you can find on images. About 1/3 of the way from the centre of NGC 4945 to the edge of frame towards 11 o'clock there is a small circular fuzz. The maps in Skytools (go down to mag 20) show a star there, so I thought it was some processing artefact. But it's on all the raws as well. Maybe I'd nabbed a faint comet! But it's visible on the DSS images of the area (Skytools is great as it can just download them and put them on the map). So not a comet I could not find it anywhere until I found this obscure reference: http://adsabs.harvard.edu/full/1964ApJ...139..899D

It just says it may be a dwarf companion. I thought it was a distant background galaxy. I can't find anymore information about it, but would love to know more about it if anyone knows how to find out more.

Thats pretty old information, there is probably something else out there to identify it, it is probably a centaurus cluster galaxy, with your camera sensitivity you will pick up quite few very distant galaxies from the Centaurus galaxy cluster out to quite a few hundred lightyears.
Nice pic.
Cheers