Stacking problems - for Fay and Duncan as they saw the problem

[Carole]

Finally sorted that problem with DSS thanks to some-one on SGL.

I had "Detect and clean remaining hot pixels" ticked in cosmetic.
Have unticked it and now the subs stack fine.

Was really weird.
Makes you wonder why these tick boxes are there if they can cause such awful problems. 

For any-one else reading this, all the subs I have taken over the last 3 images which I have stacked on my laptop (away from home) have come out with holes in the stars and galaxy cores and looked dreadful.  I almost threw away the first lot thinking they were rubbish and out of focus.

Then for the hell of it decided to process a few at a time on my desktop (where I normally do my processing), to see where it went out of focus as I knew it was focussed to start with.  Mysteriously all these subs were absolutely fine (Markarian Chain part 1).  Then the same thing happened at Blacklands processing on my laptop and again I came home and processed them on the desktop and they were OK again (M20 and Markarian part 2)

Fay and Duncan had seen the horrid results at Blacklands.

Carole

[mickw]

It went wrong on the laptop
It was fine on the desktop
repeat as necessary

I seem to remember duncan saying to compare the settings between desktop and laptop

SGL to the rescue 

[Carole]

I seem to remember duncan saying to compare the settings between desktop and laptop

I did do that, but had not found the cosmetic tab which was hidden behind the end of the tabs.

Carole

[RobertM]

Surely that's the tab you'd have found first

Sorry couldn't resist

[The Thing]

I very much doubt it was that unless the settings were very high/strong. I use the hot and cold cosmetic cleaning all the time set at 1 pixel filter size and about 85% strength (which is 'weak'). Makes sense to clean up anything slightly unmatched dark frames have left behind.

You can test it by selecting a light frame and then clicking on the test link on that tab. If the settings are too high you will see it finds millions of hot and cold pixels - which it will replace with the median or gaussian thus making the image look like lots of data is missing.

[Carole]

It was definitely that Duncan as I checked all the other settings and nothing changed until I unticked that box.

Carole