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seeker372011
06-05-2008, 10:05 PM
imaged over this last weekend of wonderful weather

NGC 6357

details

telescope-ED80
camera-QHY8
mount-CG5 -autoguided-Orion Deep Space Imager/PHD guiding
capture software-Nebulosity
exposure-2 hours (8 x 15 minutes sub frames)
location:Winston Hills

for a larger image-unfortunately with Yahoo compression :(

http://www.flickr.com/photos/91784720@N00/2470851130/sizes/o/

comments and suggestions welcome

In particular-I seem to be have become too set in my ways to go to a dark site so I image in H Alpha from home
I capture at 1x1 with an H Alpha filter and then discard green and blue channels
(this is a one shot colour camera)
would I be better capturing in say 2 x2 binned mode and then using Drizzle to upscale?

oh and image technical details aside isn't this an absolutely glorious object-also called the Crab nebula for fairly obvious reasons.

thanks for looking

Narayan

Zuts
06-05-2008, 10:29 PM
Hi,

Nice Ha capture. I am trying this a bit myself. I think you should capture in unbinned mode and 2 hours is certainly enough data.

Why dont you grab 30 to 60 minutes of OSC colour data and then blend the Ha into the red channel. You will need to align the images in Registrar first as the Ha filter slightly changes the FL and so the images wont have the same scale.

Then I think you will have the LP beat :)

To do this in photoshop.

(1) Process both Ha and OSC images in your normal manner.
(2) Load both images into PS
(3) Delete the blue and green channel data from the Ha, replacng background with black.
(4) Use Duplicate layer from the Ha using the copy into option to create the layer on top of the OSC image.
(5) Set the blending mode to lighten and fiddle with the opacity etc till you get the results you want.

You can practice with a googled colour image of NGGC 6327 and registrar until you can collect your own data.

Paul

PhotonCollector
06-05-2008, 10:32 PM
very very nice

Ric
06-05-2008, 10:52 PM
Lovely image Narayan, I always enjoy the fine detail Ha brings out.

Cheers

Astrod00d
06-05-2008, 11:00 PM
Great image Narayan, you're really bringing out the detail there. Those 15-minute subs are working well for you. I want to try the QHY8 with a UHC-S filter next time out, see if it removes some sky glow while maintaining a good colour image.

Cheers,

Rob

Alchemy
07-05-2008, 05:41 AM
the Halpha filter really brings out the structural detail ..... lovely.