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tilbrook@rbe.ne
27-07-2013, 11:01 AM
Hi,

I've never image this region before, and there's so many designations for what's going on,:confused2:( RCW 60, RCW 61, RCW 62, Gum 39, Gum 40, Gum 41, Gum 42, and IC 2944 in star formation region SFR 293.64-1.41 (http://galaxymap.org/avedisova/html/2396.html) with 51 components, including 7 masers and 18 infrared sources ) I decided to call it the jelly fish nebula.:P
Ive been twrawling the interweb for images, and there's not a huge amount . It really is a beautiful complex, rich star field, two snake like dark nebula and the jelly fish.
I'm pleased with this image, I think the colour balance is right, I usually go overboard with the magneta.
Constructive critisism welcome.

Equipment.

8" Newtonian astrograph f/4. on HEQ pro 5 mount. Orion (http://www.astronomyforum.net/wiki/Orion) mini guider.

Unmodded canon 1100D, baader coma corrector type 3.

17 x 9 minute subs, iso 800, stacked in DSS (http://www.astronomyforum.net/wiki/DSS), processed in PS7.

Cheers,

Justin.

Larryp
27-07-2013, 11:28 AM
Another nice image, Justin. You manage great reds for an unmodded DSLR.:thumbsup:

tilbrook@rbe.ne
27-07-2013, 11:30 AM
Thanks Laurie!

Quite a lot of tweaking in photo shop too.

Cheers,

Justin.

IanP
27-07-2013, 11:59 AM
Nice one, Justin. :thumbsup:
How do you find all this stuff?
Another question is, and I have to investigate it with my 60Da, what is the max exposure vs ISO for DSLRs without dramatic overexposure of stars? (in your case 9mins)
:question:

tilbrook@rbe.ne
27-07-2013, 12:16 PM
Thanks Ian!

I use guide 8 software, and pan around to find objects that I may have not imaged before. It has an overlay with deep sky images for some of them. From there I go on the inter web to see if there any images taken by amateurs using similar setups to mine.
Sometimes it's just suck it and see.
Guide 8 also has quite extensive catalogues, some of which have descriptions of angular size brightness and visual descriptions.

For the second question, I don't know. The person that might is Richard ( rmuhlac ). He seems to have done a bit of research in best iso ratings.

Cheers,

Justin.

jase
27-07-2013, 05:10 PM
Well done Justin! I partly see the Jelly fish resemblance. If could probably do with some better Ha. Perhaps time to mod your camera! Interesting target thats for sure, and I enjoyed the rich star colours you've produced too. I don't think you've gone overboard on the magenta. Just keep an eye on the green channel and check your camera white balance. I've not had a look but I suspect the green channel is slightly clipped which is the reason for minor appearance of a magenta cast. Does not distract from what is a pleasing image. Thanks for sharing.

tilbrook@rbe.ne
27-07-2013, 05:57 PM
Thanks Jase!

Nice to have input from experienced eyes.
I guess I should bite the bullet and mod the camera. I actually purchased a second 1100D to mod, even the tools to do the job.
I need to learn more on colour balance, I guess that will go up even more once I use HA blended images. I plan to use both camera's for one image, hoping this will make it easier to balance things out.

Does that sound right?

Cheers,

Justin.

jase
27-07-2013, 07:34 PM
I think you'll find you will just use the modded camera. Its a good theory but swapping cameras during imaging runs and refocusing etc, will probably wear thin after a while. With a modded camera you'll need to pay closer attention to the camera's white balance. This should make the initial steps of processing easier. You can't get back data thats clipped. Its gone for good so the initial steps in calibration, combining and colour balancing will go a long way in refining the quality of your images. There is numerous information here on IIS related to white balancing DSLRs. I'd ensure you've got a handle on this with your current non modded camera as an interim step. You're collecting great data, just need to focus on the finer points in processing. Keep at it.

tilbrook@rbe.ne
27-07-2013, 07:50 PM
Thanks again Jase!

Cheers,

Justin.

rmuhlack
27-07-2013, 08:19 PM
As Justin mentioned I've done a bit of experimenting with different sub durations and ISO settings. My approach has basically been to determine the settings which will maximise the signal:noise ratio. see here (http://www.iceinspace.com.au/forum/showthread.php?t=106775) for an example of how I have applied this.

If you find that the ideal SNR settings for a given ambient temperature result in too much loss of star colour, one strategy could be to take a second set of subs at a shorter sub length and then do a HDR combine.

h0ughy
27-07-2013, 09:48 PM
Justin,

i took the liberty of having a hack at your posted jpeg - just to show how it would look with the background evened out and removed - this was done with pixinsight. no intent to ruin your image ...

astronobob
28-07-2013, 12:32 AM
Nice work Justin, good colour and a fine target :thumbsup:
Interesting how David Re: repro hack, has levelled out the field tho, didnt notice it much myself, I should ask for CC more often, some good eyes through this forumn :thumbsup:

tilbrook@rbe.ne
28-07-2013, 10:37 AM
Thanks David!

As Bob states, didn't really notice until you did the repro.



Thanks Bob!

Yeah, it's good to ask sometimes.

Cheers,

Justin.

strongmanmike
28-07-2013, 07:35 PM
You're doing some nice stuff with that 8" Newt Justin, you are arriving at very attractive and balanced colour palettes :thumbsup:

Mike

Elio
28-07-2013, 10:00 PM
Another stunning image for un unmodded dslr, I share with who suggest to mod it now :thumbsup:

tilbrook@rbe.ne
29-07-2013, 08:12 AM
Thanks Mike!

I'm like a kid in candy shop, with the colour palettes available in PS.



Thanks Elio!

Cheers,

Justin.

jsmoraes
29-07-2013, 09:50 AM
RCW 60, RCW 61, RCW 62, Gum 39, Gum 40, Gum 41, Gum 42, and IC 2944

Justin, you can add two others names to IC2944: :doh:

Running Chicken Nebula
Lambda Cen Nebula

As you I found this region and I felt surprise with.

http://astronomia-e-astrofotos.1069742.n5.nabble.com/IC-2944-amp-Nebulosa-td933.html

tilbrook@rbe.ne
29-07-2013, 08:37 PM
Thanks Jorge!

Yep fascinating region.

Cheers,

Justin.

naskies
29-07-2013, 08:50 PM
Good job as always, Justin!

tilbrook@rbe.ne
29-07-2013, 09:53 PM
Thanks Dave!

Cheers,

Justin.

Ross G
29-07-2013, 10:21 PM
Another great looking photo Justin.

Again, I really like the detail and colours you bring out.

Nice composition as well.

Ross.

tilbrook@rbe.ne
30-07-2013, 05:54 PM
Thanks again Ross!

I really like this nebula, I'd love to see it done by the more experienced on this forum.

Cheers,

Justin.