helix from Astrofest 2011

[h0ughy (David)]

taken over 4 nights - there is about 8 hours worth in this - gee its faint to get detail of the outer shell - far outside the reach of the cooled 40D i am afraid.

[Ross G]

Hi David,

Sharp and nice colours.

You have captured a lot of detail.


Thanks.

Ross.

[tornado33]

I can see that northeast arc there, so its nice and deep too.
Scott

[Paul Haese]

You got the main arc, and yes it is a tough object to image. What was your sub exposure length David?

[jjjnettie (Jeanette)]

Very nice Dave.
It's a hard target for sure.

[h0ughy (David)]

Originally Posted by Paul Haese

You got the main arc, and yes it is a tough object to image. What was your sub exposure length David?

mainly 5 min subs but had about 1.5 hours of 10 min subs - smoke and some high cloud limited me to the shorter subs just in case i lost a few

[Paul Haese]

Yeah that makes sense. Hence the reason for the background noise too. Really the subs have to be long enough for the signal to over whelm the noise. Mathematically it should be around 10 minutes but empically I find that 15 to 20 minutes works better for me. Perhaps next time go longer David. Like you said though cloud can make getting any data a problem.