FWHM Help

[Robny]

Hi All

Just looking at FWHM, I understand the concept, what it is and why it matters.

I'm using the 'SubFrameSelector' in PI and this is my results (attached), based of this (which I know is pretty bad - neighbours decided to have a fire on the only clear night) I would need to discard everything from where the graph sky rockets?

As I said, there was a lot of smoke in the air and I also had a meridian flip in the middle of the session.

Thanks 

Rob 

 

Edited January 13, 2021 by Robny
Added image in line

[Freddie]

You don't "need" to discard them. Do a stack with and one without and check what difference you can see between the two stacks.

[wimvb]

You can add a weight factor to the subs

(Max - FWHM) / (Max - Min)

Where Max is the highest FWHM and Min is the lowest value. In this scenario, all sub contribute, but subs with a small fwhm contribute more. Experiment for best results.

[Robny]

Thanks......

So ideally the lower the FWHM the better

[wimvb]

Yes, lower fwhm = tighter stars

In post processing, you can tighten the stars (and details) a little more with deconvolution

Edited January 13, 2021 by wimvb