Experiment with Percentage of Subs being Stacked

[Stub Mandrel]

It's often really hard to decide what percentage or number of frames to stack in Autostakkert for good results.

With a massive 14,640 frames of Saturn available from last night, all of pretty mediocre quality, I've stacked different percentages with 1.5 drizzle and these are the results.

Every final image has had exactly the same set of wavelets applied, in Registax.

I think using some of my less-good data is worth it, as it ensures that the shortest stack is truly noisy and the 100% one is not too full of detail, a sort of worst-case!

Out of interest, relatively under-exposed, shorter subs have given me better results than this.

1% - 146 frames

2% - 292 frames

5% - 732 frames

10% - 1,464 frames

16% - 2,342 frames

25% - 3,660 frames

50% - 7,320 frames

100% - 14,640 frames

 

[JimothyC]

5% looks best to me. What did the quality graph look like when you analysed them? I tend to go by what that says and try not to pick anything that falls too far below the 50% line. 

[MarsG76]

Ditto for 5% here in this example to me also.

[MarsG76]

Voted... Unanimous so far...

[Stub Mandrel]

Here's the analysis:

The problem with the analysis graph is that it is stretched so the top is the best frame and the bottom is the worst. A few outstanding frames , then lots of good ones and no bad ones can give a misleading impression that most of the frames are poor.

[Stub Mandrel]

Here's 5% with a bit of Astra Magic. Still considerably inferior to the ones I got a week or two ago.

[JimothyC]

Try running it through PIPP first and see if that makes much difference. 

[Stub Mandrel]

49 minutes ago, JimothyC said:

Try running it through PIPP first and see if that makes much difference. 

I always  use PIPP first as a matter of course, but leave the debayering to AS!3 as it does a much better job of drizzling.

[sloz1664]

Well Neil certainly better than my efforts at Planetary. Couldn't get the results, for the all effort I put in and decided DSO's were my cup of tea.

Steve