M6 - Butterfly Cluster

[PKay (Peter)]

Buggered if I can see a butterfly.

Anyway this was on the bucket list so done now.

15 of 60 sec subs. Gain = 70.

Even with short subs and low gain, most of the stars saturated.

Cropped to within an inch of it's life.

Said many times...'we have to try these things'.

[Imme (Jon)]

What was your offset at Peter?

[Atmos (Colin)]

You've caught nice colour variations in the stars so you've captured the cluster nicely.
As for the butterfly, looking down the North South line it makes a bit of a line. This colour be the length/body of the butterfly.... It just doesn't have any wings

[PKay (Peter)]

Thanks Colin and Jon.

Jon: I set the 'offset' (also called Bias) to 50 and that's where it stays for all my imagery.

Colin: You have a good imagination!

[Imme (Jon)]

Originally Posted by PKay

Jon: I set the 'offset' (also called Bias) to 50 and that's where it stays for all my imagery.

I thought the offset/bias needed to change with different Gains?????
Do you find any clipping or lost range at different gains?

[PKay (Peter)]

Hi Jon

From my experience there is no need to change the BIAS(offset). The newer cameras ( I believe) it is set and you cant change it. 50 is about right.

Yes high gain settings can cause all sorts of issues.
I use high gain (400) to find and centre a target, then turn it down.

For imaging I never go above Gain of 200.
Unity Gain (139) is a good place to start for Nebula.
To get star colour Gain set to 70 is about right.
And of course a variety of exposure lengths depending on the target.
Bright star fields 30 - 60 sec should work.
Dim Nebula 60s - 120s - 240s - 480s (assuming guided).