Windy Carina

[andyc]

I set up the scope on a very windy evening after a strong cool change came through, with the aim of learning some more about the polar alignment. After midnight, the Moon had almost set and I thought about trying a few shots, but there was no point in setting up the guiding because of the wind. But having had a go at Uranus and found a few subs not trailed at 30 seconds, I turned to Eta Carinae, which was only about 20deg up in the SE, set the camera snapping and left it for 45 minutes. The result is here!

35 x 30 second exposures at ISO 1600 (yes Raymo, the ISO is higher :P though I'm not actually quite sure why!), 150mm f/5 Newtonian on HEQ5pro. I discarded 44 more exposures due to the wind and periodic error. Stacked and processed in PI and a few tweaks in Photoshop 'cos my PI kung fu isn't all there yet!

Larger version of the wider view is here (http://www.pbase.com/andycasely/image/158072986/original).

Larger version of the central area (full resolution) is here (http://www.pbase.com/andycasely/image/158161022/original).

[lazjen]

Nice work - good to get something on those windy nights!

[jsmoraes]

Very good image, despite of 30 sec subs. Very nice, sharp and good color. Very interesting the capture of red area of nebula.

[cometcatcher]

A very nice Eta C Andy. :thumbsup:

[LightningNZ]

Nice work Andy. Good to know what I'm in for with a similar scope. :)

[andyc]

Thanks guys!

Jorge, so far as I can see, the redder bits of nebulosity are real (they're on an ESO image i saw too, and probably many others). The colour suggests they are parts of the nebulae where the hydrogen emission is reddened by dust scattering of the blue Balmer lines but not so much of the red - a bit like the difference between NGC3576 and NGC3603.

[jsmoraes]

And natural. I have seen many photos of Eta nebula. Each one with different colors. Some very red, others very blue. I prefer like yours. There are red, but this part of nebula is more blue, with some reflexion of red.

The keyhole is very clear, with many details. A more sharp filter applied with mask will bring out the interior and their details. You did with 150 mm, I did with 305 mm. Your photo has as much details than mine. http://astronomia-e-astrofotos.1069742.n5.nabble.com/file/n1479/keyhole-20140417-detail.jpg (from http://astronomia-e-astrofotos.1069742.n5.nabble.com/NGC-3372-2014-td1414.html)

And it was not with hour of exposition. That's the point ! :thumbsup: Great capture !

[chiaroscuro]

Hi Andy,

Very nice shots, and nice and sharp. Do you use some software for focussing?

Cheers
Luke

[Craige]

Nice Andy!

Cheers Craige

[multiweb]

Awesome. Very good details around the keyhole. :thumbsup:

[Rex]

Nice going Andy!

[andyc]

Thanks for the nice comments everyone :thanx:. Am looking forward to trying this when it's higher in the sky, with longer subs, and maybe from a darker site!



Hi Luke, What I do for focusing is use the live view from the back of the camera (as described by Jerry Lodriguss as an effective way of focusing a DSLR (http://www.astropix.com/HTML/I_ASTROP/FOCUS/Live_View_Focusing.HTM)). You can see a reasonable number of stars in live view, usually down to below 4th/5th mag. So I point at a moderate/faint star that you can see in live view, zoom in to 10x on the live view, then focus as well as I can. There's enough movement on my focuser to be fairly confident of a good focus. I doubt that more exacting focusing methods would make a great difference for my set-up.



Jorge, you're very kind! But your image (as you might expect) definitely shows smaller stars, and much greater definition of the dark patches in front of the nebula - I overlapped my full resolution image with yours. So I have still some way to go to match your image :).