ASI 183MC Colour bands after stacking.

[Synchronicity]

Hi all

I'm back imaging after a couple of years of inactivity/discouragement/hardware problems and last night was for getting everything set up, communicating and pointing in the right direction.
It went really well so I managed to get 90 minutes of data on the Eastern Veil nebula.  Framing is poor and focus not perfect but tonight's question is about what happens when I stack the images.  I know I've seen this before browsing posts but can't find it and can't think of words that turn anything up in the searches.

This is a screen-shot of DSS stacking the data with default settings (best 80% of frames).  In this case it has the darks, flats and bias included but it's the same without them and the same stacked with ASTAP.
I've just opened the stacked image in PI, debayered and then applied the STF to see what it's like.  The hatching is also there without debayering.

The number of bands increases with more light frames stacked so I'm assuming it's related to stacking but just don't know where to start tweaking settings.

Below is a screen-shot of 2 light stacked and then a single light frame.

Taken with my brand new ASI183MC Pro cooled to -22 degrees, gain set to 200, Optolong L Enhance filter on an Esprit 80 with field flattener. Mounted on a NEQ6 Pro, captures done with APT.
Bortle 7/8 sky and 97% moon

2 light frames only stacked.

A single 180s light frame.#

NGC6992_0009_Bin1x1_180s__22C.fit

Any assistance or pointers much appreciated.

Thanks

Michael

[Adam J]

4 hours ago, Synchronicity said:

Hi all

I'm back imaging after a couple of years of inactivity/discouragement/hardware problems and last night was for getting everything set up, communicating and pointing in the right direction.
It went really well so I managed to get 90 minutes of data on the Eastern Veil nebula.  Framing is poor and focus not perfect but tonight's question is about what happens when I stack the images.  I know I've seen this before browsing posts but can't find it and can't think of words that turn anything up in the searches.

This is a screen-shot of DSS stacking the data with default settings (best 80% of frames).  In this case it has the darks, flats and bias included but it's the same without them and the same stacked with ASTAP.
I've just opened the stacked image in PI, debayered and then applied the STF to see what it's like.  The hatching is also there without debayering.

The number of bands increases with more light frames stacked so I'm assuming it's related to stacking but just don't know where to start tweaking settings.

Below is a screen-shot of 2 light stacked and then a single light frame.

Taken with my brand new ASI183MC Pro cooled to -22 degrees, gain set to 200, Optolong L Enhance filter on an Esprit 80 with field flattener. Mounted on a NEQ6 Pro, captures done with APT.
Bortle 7/8 sky and 97% moon

2 light frames only stacked.

A single 180s light frame.#

NGC6992_0009_Bin1x1_180s__22C.fit 38.61 MB · 3 downloads

Any assistance or pointers much appreciated.

Thanks

Michael

One thing that jumps to mind is are you using the correct debayering settings in DSS? 

[Adam J]

5 hours ago, Synchronicity said:

Hi all

I'm back imaging after a couple of years of inactivity/discouragement/hardware problems and last night was for getting everything set up, communicating and pointing in the right direction.
It went really well so I managed to get 90 minutes of data on the Eastern Veil nebula.  Framing is poor and focus not perfect but tonight's question is about what happens when I stack the images.  I know I've seen this before browsing posts but can't find it and can't think of words that turn anything up in the searches.

This is a screen-shot of DSS stacking the data with default settings (best 80% of frames).  In this case it has the darks, flats and bias included but it's the same without them and the same stacked with ASTAP.
I've just opened the stacked image in PI, debayered and then applied the STF to see what it's like.  The hatching is also there without debayering.

The number of bands increases with more light frames stacked so I'm assuming it's related to stacking but just don't know where to start tweaking settings.

Below is a screen-shot of 2 light stacked and then a single light frame.

Taken with my brand new ASI183MC Pro cooled to -22 degrees, gain set to 200, Optolong L Enhance filter on an Esprit 80 with field flattener. Mounted on a NEQ6 Pro, captures done with APT.
Bortle 7/8 sky and 97% moon

2 light frames only stacked.

A single 180s light frame.#

NGC6992_0009_Bin1x1_180s__22C.fit 38.61 MB · 3 downloads

Any assistance or pointers much appreciated.

Thanks

Michael

Well I cant see any of this in the single frame so it is a issue with your stacking.

I use APP so no longer an expert in DSS, but you need to look at your file inport settings i think.

Options, Settings, Raw/FITS DDP Settings, select the tab FITS Files and use Monochrome 16 bit FITS, Color CCD Camera and select Generic RGGB in the pull-down menu.

Adam

Edited August 15, 2022 by Adam J

[Adreneline]

There's some interesting experience being shared here which might be helpful - maybe?

Adrian

[Synchronicity]

20 hours ago, Adam J said:

Options, Settings, Raw/FITS DDP Settings, select the tab FITS Files and use Monochrome 16 bit FITS, Color CCD Camera and select Generic RGGB in the pull-down menu.

Was exactly the the change I needed to make. Thanks!

 

14 hours ago, Adreneline said:

There's some interesting experience being shared here which might be helpful - maybe?

Different issue but lots of great advice on selecting cain, exposure length etc. Thanks!