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avandonk
31-05-2009, 11:26 AM
With weather luck and no Moon may get to finish this. Here is an interim image of the Rho Oph region mosaic I am working on. Needs more data.

1.4MB

http://d1355990.i49.quadrahosting.com.au/2009_05/mos01crlarge_8.jpg

Bert

glenc
31-05-2009, 05:56 PM
Another great image Bert. :thumbsup:

gregbradley
31-05-2009, 06:05 PM
That's a beauty Bert.

Your images have a unique approach and perspective. Nothing quite like it anywhere else.

Greg.

avandonk
01-06-2009, 08:51 AM
Thanks for the comments folks. Looks like the weather and Moon will halt data collection for a while. So I squeezed out what I could from the data I had.

The mosaic is made up of two panels. Taken with the Canon 5DH and Canon 300mm F2.8L at f/5 and 400 ISO. The fridge temperature was at -5C so the sensor temperature was 12C.

LHS
Exposures 10x1m, 5x4m, 17x8m, 19x16m.

RHS
Exposures 10x4m, 10x8m, 10x16m.

The 1m exposures were needed in the LHS panel to record Antares without saturating too much.

I used my HDR process to produce the two panels and then used Registar to produce the mosaic. A lot of fiddling needed to hide the join.

More data is needed but here is a 8MB image

http://d1355990.i49.quadrahosting.com.au/2009_05/rhomosbig.jpg

The reflection nebulae and dust in this region are very faint so maximising the signal to noise ratio as usual is the one factor that gives any sort of decent image. Stacking many dithered images does really minimise any residual noise. Just compare the LHS to the RHS.

Bert

iceman
01-06-2009, 09:05 AM
Beautiful patch of sky, wonderfully presented.

Nice work bert!

avandonk
01-06-2009, 11:48 AM
Thanks Mike. I have figured out after forty years in science that current best practice is exactly what it purports to be. Just current best practice that can and will be improved incrementally. The three million dollars worth of equipment in my laboratory at CSIRO was tweaked to the nth degree over many years so we could collect the best data on the planet. We could get better data as far as signal to noise was concerned than setups at the biggest synchrotrons. The big synchrotrons now use methods developed in my laboratory. I am using all the knowledge I gained over forty years to apply it to astrophotography. It is a slow process groping in the dark for some nuggets of better methods. Perseverance and constant attention to detail is the trick. Most of all though is to go out and do it! And practice practice practice

Bert

h0ughy
01-06-2009, 12:45 PM
Fantastic Effort Bert. As usual I am in awe of these images. LOL if you keep going like this Bert you will have an all sky survey soon - to our delight!

jase
03-06-2009, 09:52 AM
Stunning work Bert. May give me a few ideas... I think you could blend the panels in better however.

avandonk
03-06-2009, 10:48 AM
Jase it is not worth the trouble to try to match panels as I intend to collect more data so matching panels will not be complicated by even minor vignetting as is the case at the moment. This is a just a teaser image and to also see how panels don't match. I tweaked up the EQ6 yesterday to remove the tiny bit of backlash in declination as it is showing up as a slight elongation of stars when the mount is pointing near due East. There is a 50 50 chance of flopping either way even when properly balanced statically . I do have two 80mm 12V 0.5A fans cooling the heat exchangers on the fridge and this can drive any instability to show up. A dynamic balance can only be attained by adding an extra adjustable weight.

I settled on this orientation of the image after contemplating all possible variants. We humans always assume that illumination of any scene comes from above. So it looks more 'natural' subconciously to put the brightest object at or near the top. This comes from millions of years when our ancestors only had the Sun and the Moon as light sources.

Bert

multiweb
04-06-2009, 06:28 PM
Awesome shot Bert. Very nice colors. :thumbsup:

prokyon
05-06-2009, 06:22 AM
Hi Bert,

wow, this pic is great!!! :thumbsup:

Perfect job!

cheers

werner

tornado33
05-06-2009, 03:05 PM
Very nice. I just wish I could get some decent imaging weather here.
Scott

telemarker
05-06-2009, 08:13 PM
A fabulous image of a beautiful part of the sky.
Look forward to seeing the completed image.

Cheers