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Placidus
03-02-2015, 12:58 PM
Just a tiny snippet of the Vela SNR. The bright bits are easy, but here we've tried to show some of the super-faint pre-existing material into which the SNR has expanded, and what is happening there. Total of 24 hours in 1 hour subs. Red: SII (9hrs), Green: H-alpha (9hrs), Blue: OIII (7hrs). Sadly courtesy of weather, most of the subs were taken under a waxing gibbous moon, so the background is a bit grittier than we'd like. On the other hand, seeing and transparency were good for high summer.

Big raw image here. (http://www.mikeberthonjones.smugmug.com/Category/Supernova-Remnants/i-9mZNv6D/0/O/M%20Pencil%20SII%209%20Ha%209%20OII I%207hrs.jpg)

Trying to mend our rotten ways and give more emphasis to the red SII channel, without departing too far from our desire to avoid the blood-and-intestines magenta excesses of natural colour. We'd prefer the true Australian colours of green fields, golden wheat, and blue sky.

We can now see more detail in the yellow dragon's head, facing left, and breathing multi-coloured flames, just above the brightest whitest part of the pencil. If you look at the one-to-one image, you will see that the dragon has scales, even over the dark reptilian eye.

The ESO 2.2 metre image (http://apod.nasa.gov/apod/ap120924.html) shows that the scales are where they should be.


Notice that the Pencil seems to be in a clear space, a horizontal dark band across the central third of the image, whereas there is much smooth background H-alpha and some SII nebulosity, presumably pre-SNR material, in the upper and lower thirds of the image.

At top right, we see something different: multiple tangled shock fronts, showing predominantly in H-alpha, forming a rough sphere, and just plausibly part of a separate explosive event.

Field 30' arc, north on the left. Aspen 16M on 20" PlaneWave.

Very best,
Mike n Trish

Regulus
03-02-2015, 01:15 PM
That's a nice image Mike, and I like the colour choice here too.

Bassnut
03-02-2015, 06:48 PM
Excellent Mike, lots of detail. I found colour balance very difficult on this, yours looks fine.

Placidus
03-02-2015, 07:07 PM
Thanks Trevor! :)



Cheers, Fred. Getting there.

RickS
03-02-2015, 08:20 PM
Seems to be a remarkably tricky object to do well. Very nice job, Mike!

Ross G
04-02-2015, 05:13 AM
A great looking closeup photo Mike.

Well composed.

As always, amazing detail and sharpness.

I like the description as well.

Ross.

multiweb
04-02-2015, 07:40 AM
Great image scale and details Mike. Looking at the ESO pic I thought yours should be the benchmark ;)

Placidus
04-02-2015, 08:10 AM
Thanks Rick. Glad you like it. Actually the most difficult thing about the last shoot was we invited the neighbours up to watch us set up for the night. 4WD through the paddocks. Great expectancy. RA motor wouldn't work. The mighty detective (that's me) quickly found a never-soldered connection on the motor control board. It had worked fine for 5 years! Dodging cows and horses, back to the house. Fixed in 2 minutes, but we were too nervous to take the army of guests back up in case it put the mokkers on it. Worked fine of course. The guests watched "Who framed Roger Rabbit" while we photographed.



Thanks muchly Ross. The composition required a lot of cropping at the bottom left. I can now see that there's a lot of really interesting faint stuff out of field toward top right. So if we were to start again next year, we might put the full frame to include more at top right.



Cheers, Marc ! There's a great 4 page article in this month's AS&T about how most behemoth (8 metre) telescopes don't work as planned, e.g. they don't hold collimation. Lovely problem to have, though.