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gregbradley
24-07-2011, 03:20 PM
I took some O111 and S11 data last night (a surprisingly clear night)
to go with the Ha I took a week or so ago.

The S11 is a bit weak so I thought I would do a bicolour narrowband version.

I intend to add more to this later including RGB stars but for now this is the bicolour version.

There is also a crop that highlights the streaking O111 data in the centre area.

Planewave CDK17 and reducer at F4.5, FLI Proline 16803, PME mount.

http://www.pbase.com/gregbradley/image/136649935/large regular

http://www.pbase.com/gregbradley/image/136649935/original large

http://www.pbase.com/gregbradley/image/136650988/original Cropped version.


Greg,

renormalised
24-07-2011, 03:27 PM
Exquisite, Greg:)

The 3D effect of the blending and processing of the Ha and OIII really comes off well. And, I like the colour in this rendition. What also helps is the amount of detail in the neb as well.

I wouldn't add anymore to it:)

jase
24-07-2011, 04:21 PM
Nicely done Greg. The Ha+OIII blend has worked well. Aperture certainly brings out the OIII blast, like spokes on a wheel. Cool! Perhaps add some RGB stars from one of your other helix nebula images to complete the mission.

May I ask why you are uploading images to the web embedding an AdobeRGB profile?

gregbradley
24-07-2011, 05:34 PM
Thanks Carl.



Yes I do have a few Helix's lying around. Good idea.
Adobe RGB 1998 as that was the colour space for the Malin awards.
Why does it make much difference? John at the Malins said it had a wider colour space than sRGB.

Greg.

jase
24-07-2011, 05:49 PM
Yes it does have a wider gamut, but is of little use for online material. Most web browsers don't support it. I don't think you're doing your work any favours in using aRGB. I suggest doing some research on the topic. Plenty of info out there (here (http://www.kenrockwell.com/tech/adobe-rgb.htm) for example).

atalas
24-07-2011, 05:58 PM
Nice work Greg.

rcheshire
24-07-2011, 06:20 PM
Really nice Greg. The choice of colours is very effective - accentuates the detail beautifully.

multiweb
24-07-2011, 06:29 PM
Super shot Greg. Picked up so much details. Amazing. :thumbsup:



It does but it's more suited for 16 bit file format such as TIFF or Targa. You've uploaded a JPEG which is 8 bit per channel. You got lucky with this shot but you'll get funky transitions (banding) in areas where there is a smooth gradient. To be avoided for 8 bit representation. I you go to print then it's a different deal.

strongmanmike
24-07-2011, 06:34 PM
17" F4.5 huh?...niiice ;)...rather extensive that :eyepop:

I see you have gone with some hard processing for extreme depth at the expense of fine natural details and that's cool.

The dilemma here is trying to showcase both the star burst features in the OIII and the radiating cometary globule details in the Ha in the final image. I found blending the Ha and OIII data was a compromise in the end showcasing both well was very difficult (Jase somehow managed it with the 24" data he gathered though - magician?).

From memory even deep SII on this object is almost featureless?

Nice work mate :thumbsup:.

Mike

John Hothersall
24-07-2011, 07:10 PM
Love the Ha undulations but prefer the blue to be deeper, Ha/O3 bicolour nb is difficult to do for me anyway, but the Ha is king here showing splendid structure.

John.

jase
24-07-2011, 07:30 PM
One word - masks. With the OIII channel I created a hide all mask, then pasted the OIII data into the mask itself. It was re-layered over a SHO blend where the OIII was only blended at 40% allowing the globs to come through. This allowed for finer control of the OIII structure and Ha details. Am making it sound simple, but it may take a few iterations to get the right blend.

strongmanmike
24-07-2011, 07:33 PM
...as I said, a magician! :thumbsup:

Alchemy
24-07-2011, 09:17 PM
Going to mirror johns comment, the hydrogen is awesome, would like the oxygen just to be a more aqua/ blue hue.....

Still an incredibly deep image .

Can't get over the standard of some of the imaging of late, it's moved way beyond what I can do.

Bolts_Tweed
24-07-2011, 10:03 PM
Wow Greg - that is so good it is scary and it is not finished.

Congrats mate

MB

Ken Crawford
25-07-2011, 03:30 AM
Masks Rock! They provide the ultimate control and using object masks like this really helps define those hidden structures. Using them with clipping masks that are color mapped in a layer group can give even more control as the layer group has it's own blending modes!

Nice work - the OIII streaks can be really enhanced as the look like spokes!

Congrats on a fine image . . . .

Tom Davis
25-07-2011, 12:00 PM
Super, Greg!!! Nice shells!!!! Now take an RGB image and replace the central nebula with it. That would be a stunner!

Tom

gregbradley
26-07-2011, 07:49 AM
Thanks Tom.

I'll do just that. This is really a work in progress as I gather more data. Its a bit of a pain in that its not ready to image on the western half of the sky until about 1am.

I'll have to learn how to setup automated meridiain flips.

Greg.

Ross G
28-07-2011, 06:08 AM
An outstanding phtoto Greg.

As the others have noted, it has an amazing 3D look.


Thanks.

Ross.

gregbradley
28-07-2011, 07:26 AM
Thanks Ross.

I am in the process of collecting more data for this one.

I think I have gotten about another 5 hours so far of Ha and LRGB.

If this clear weather keeps up I'll just keep adding hours. The seeing was really good last night too. Tightest stars I have seen for ages.

Greg.

Paul Haese
28-07-2011, 12:34 PM
Round round round stars. Great detail, but I reckon it needs RGB data in the center masked in of course. Lovely work and not much to dislike. Well done. With meridian flips just make sure the data gets put into another file so you can calibrate and rotate it. Having a rotator helps though. Must get one of them myself.

gregbradley
28-07-2011, 03:15 PM
I think there must be some software that does meridian flips automatically along with a plate solve. CCD Commander or similar?
Unfortunately this one requires a meridian flip at about 2:30am.

I have another 6 hours to add, most of that is RGB. I think I'll continue to accumulate data whilst the weather is good.

Greg.

Paul Haese
28-07-2011, 03:39 PM
One person that does know for certain about which program is Wysiwig (Mark). Send him a PM, he has his PME and imaging rig sorted to auto meridian flip and rotate.