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View Full Version here: : Helix nebula response to filtering


tornado33
29-07-2006, 11:39 AM
Hi all
Here is a image of the helix nebula taken last night, 4x10 mins (40 mins total) no nebula filter used. Its longer then the 30 mins used with the triffid nebula image I took , see http://www.iceinspace.com.au/forum/showthread.php?t=12007
I expected to get a much deeper image but it didnt happen, and this was despite the fact that the Triffid was well past Zenith, but the helix was very near the zenith and thus better placed for imaging. So it seems that some objects do better without filtering then others. The helix definately requires the UHCS filter for best results.
Scott

h0ughy
29-07-2006, 02:22 PM
nice image, I found the helix to have a very low surface brightness and will tak much longer to get the same level of brightness required to achieve a good image and reveal details. But thats only my opinion.

tornado33
30-07-2006, 09:06 AM
Youre right, it is VERY faint in surface brightness, and a filter helps pull it from the sky background. I suspect a filter wont be necessary at a dark site
Scott

Striker
30-07-2006, 09:18 AM
Still a really nice image Scott...I know how difficult this target is to get much detail and brightness on this image....something I am going to work on later next month.

Yours is about 500% better then my first attempt...I will have a go with the UHC-S filter.

tornado33
30-07-2006, 11:04 AM
Thanks Tony, I reckon you will do well with a focal recucer on your rig, that will concentrate the faint light of the helix on a smaller area.
Scott

Lester
30-07-2006, 11:13 AM
Hi Scott,

that is a very deep image= outer swirl and also the small galaxy within the bottom of the Helix. That galaxy is not captured very often. Don't know if it is possible, but all it needs is the sky to be darkened without losing the outer swirl.