Eta Car 2nd attempt

[ChrisM]

Not being happy with the framing of my first quick attempt, I've had a second go at Eta Car - this time using a x0.8 focal reducer, which means the scope is working at f/4.2 and 528 mm FL.

Focus was trial and error via a series of a dozen or more 10 sec exposures (and viewed on the camera's display while I lay on the obs floor. I think that I might try a mirror next time.)

The pic attached is just a single 45 second exposure, with the red channel cut back to 65%, and then stretched and re-sized in PS. Once again, I've used the jpeg file, as my version of PS doesn't handle Canon raw (CS2) files.

Looks like I've got at least one bright star blooming. Interestingly, this is evident on the same star even in the 10 second snaps that I took when adjusting the focus.

Chris

[NeilW]

Very nice Chris. I'm just starting to embark on this AP journey, and to see that you can get such great results with one exposure is very encouraging!

Thanks,

[ChrisM]

I've found my way, for the first time, through Pix Insight, courtesy of some of Harry Page's beginner's tutorials, and done a repro of the pic posted above.
See here http://astrob.in/full/7267/ for a full size image.
It's still just the 1 x 45 second sub, so no stacking was necessary.

I've been doing a side by side comparison with Peter Ward's amazingly exquisite shot of Eta Car on the Deep Space Images forum. http://www.iceinspace.com.au/forum/showthread.php?t=88034&page=3 He used an Astro Physics 305 mm f/3.8 Astrograph and I gather that he used several hour's exposure. What surprised me then, was that his pic does not pic up very many more stars at all than my 45 seconds through a 5" refractor. However, his shot has far, far more nebulosity, and the image scale is a little different, so the stars stand out better.

I'm now waiting for clear skies to get some more subs.
Chris

[MGTechDVP]

Breath taking, well done.


Mariusz