DSS snowstorm?

[Russe]

Maybe one of you knows this - it's quite baffling.

So, I'm working on M57 with a very meager setup (HEQ5, Mak127, SPC880 LX modded). I'm enjoying learning the ropes.

So I got 50 odd 45s exposures. First DSS doesn't stack them, because of not having enough bright stars, so I got it stacked in Reg6.

Now I wanted to apply darks, flats and bias.

But this is what I got in DSS:

After only registering the stacked file, it suddenly turns into a white snowstorm as you can see below. I've tried it with single exposures, with or without any of the extra thingys we're supposed to take and I've clicked myself through the various options of hot pixels and median stacking etc. etc.

No change.

I thought that you get a near ready picture in the end in DSS which you can play with?

Ideas?

stacked 45s tif.tif

[Russe]

The other attached file is the actual stacked tif file out of Reg6.

By the by, would you only apply flats and darks to stacked pic files out of reg6 or to the pics saved on the wavelets page? Probably the first I reckon.

[Russe]

This is before, by the by

[NickK]

Well the stacking is starting to pull out some data:

Looking at this and the hot pixel in the top right corner moving the signal-noise ratio of the subs is probably causing some issues. Look for a sigma noise option as this will remove moving noise between frames.

[Russe]

in DSS? or in Reg6?

[Russe]

by the by, this is all before flats-darks-bias

[NickK]

Not being a DSS or registax 6 user I can't say but the technique is usually named sigma noise rejection or sigma stacking.

[NickK]

by the by, this is all before flats-darks-bias

Usually these are applied to each sub to remove the noise before stacking - non-dynamic noise such as the camera noise from the darks+bias will appear in the stacked image as it will end up stacked too..

[Russe]

ah, then I need to stack the pics together with the flats and everything...

god...

maybe I should by nebulosity

what are You using? PixInsight or Nebulosity?

[NickK]

I started with Nebulosity then moved onto Pixinsight.

However before this - have a look around, usually tools have a way to automate things. DSS/RS6 probably have too.

[Steve Ward]

There are a lot of adjustment you can make at the end of DSS with the various sliders below your 'final' image.

The image that DSS gives you is often a dreadful looking thing so don't panic.

I only use these adjustments as I find PS too much faffing around , have a ply with the histogram settings and you'll be amazed at what's in there..

For a great tutorial on DSS basics try here

Steve.

[Russe]

Thanks - great advice!