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deep space stacker


Bottletopburly

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How do you pick a reference frame in DSS so plane tails are taken out using median clippa ,or do i just ditch the subs with plane trails ,i read choose a reference frame  but can't see how to do that .

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When you stack what spec do you use.

 

You have the options of 

 

Average

Median

Kappa Sigma clipping

Median Kappa Sigma clipping

Auto adaptive weighted average.

 

If you use the Kappa sigma clipping it should automatically remove the plane trails for you 

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If that doesn't work then I seem to remember (and its been a while since I last used DSS) that after you have loaded in all your frames and clicked 

Check All

If you then click on any of your lights which ever one you click on will become the reference frame.

You then register checked frames and stack as normal.

Edited by Graham
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Thanks @Graham,took out a plane but left a satellite trail from one sub  omitted subs for now only two lost subs well three one has oval stars so deleted that one .

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58 minutes ago, Graham said:

If that doesn't work then I seem to remember (and its been a while since I last used DSS) that after you have loaded in all your frames and clicked 

Check All

If you then click on any of your lights which ever one you click on will become the reference frame.

You then register checked frames and stack as normal.

Hi Dave - picking up on Graham's point, if you register your images but don't stack them automatically, your lights should be ordered in terms of quality. DSS assigns a score in the frame list window - the higher the score, the better the quality of the data. You can then right-click your best frame and you'll get a pop-up menu where you can tag the frame as a reference frame. This frame will then be used by DSS as the goto reference during the stacking process - which you can then run as the next process in your workflow. The clipping method selected determines the removal of satellite or plane trails more than a reference frame choice. I never throw a good frame away with a satellite trail because Sigma Clipping is so effective. Hope that helps

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5 hours ago, Chris P. said:

Hi Dave - picking up on Graham's point, if you register your images but don't stack them automatically, your lights should be ordered in terms of quality. DSS assigns a score in the frame list window - the higher the score, the better the quality of the data. You can then right-click your best frame and you'll get a pop-up menu where you can tag the frame as a reference frame. This frame will then be used by DSS as the goto reference during the stacking process - which you can then run as the next process in your workflow. The clipping method selected determines the removal of satellite or plane trails more than a reference frame choice. I never throw a good frame away with a satellite trail because Sigma Clipping is so effective. Hope that helps

Thanks Chris that was the answers I was looking for ? I will have a restack,and see how it comes out 

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Chris is spot on, also do quality darks, flats and bias frames, ideally taking darks take the camera off the scope and stick it somewhere really dark i.e. a box, it can be amazing how much light can get in if your taking darks on a scope, flats are another one, don`t go too bright with them and take them for all filters, i find a ADU value of around 20,000 - 23,000 works well with DSS

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Thanks rob , I use dithering instead of darks , and then take bias frames and load into dark calibration in DSS  as that’s the preferred option when dithering, seems to work well and images looking less noisy , I will do the bias in the house though ,

how do you measure the adu of flats  

2 hours ago, red dwalf said:

Chris is spot on, also do quality darks, flats and bias frames, ideally taking darks take the camera off the scope and stick it somewhere really dark i.e. a box, it can be amazing how much light can get in if your taking darks on a scope, flats are another one, don`t go too bright with them and take them for all filters, i find a ADU value of around 20,000 - 23,000 works well with DSS

 

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Do a flat in your program of choice, then usually if you put the mouse pointer on the image it should give you a reading somewhere, in nebulosity it shows the reading in the bottom right hand side

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2 hours ago, Bottletopburly said:

Thanks rob , I use dithering instead of darks , and then take bias frames and load into dark calibration in DSS  as that’s the preferred option when dithering, seems to work well and images looking less noisy , I will do the bias in the house though ,

how do you measure the adu of flats  

 

Just tried that and it is a lot less noisy!!

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On 01/03/2019 at 21:44, Graham said:

When you stack what spec do you use.

 

You have the options of 

 

Average

Median

Kappa Sigma clipping

Median Kappa Sigma clipping

Auto adaptive weighted average.

 

If you use the Kappa sigma clipping it should automatically remove the plane trails for you 

 

On 01/03/2019 at 23:07, Chris P. said:

Hi Dave - picking up on Graham's point, if you register your images but don't stack them automatically, your lights should be ordered in terms of quality. DSS assigns a score in the frame list window - the higher the score, the better the quality of the data. You can then right-click your best frame and you'll get a pop-up menu where you can tag the frame as a reference frame. This frame will then be used by DSS as the goto reference during the stacking process - which you can then run as the next process in your workflow. The clipping method selected determines the removal of satellite or plane trails more than a reference frame choice. I never throw a good frame away with a satellite trail because Sigma Clipping is so effective. Hope that helps

Well i found the reference tab thanks chris ,and i use Kappa sigma method  ,now it removes the trail  red and green but find it not good at removing white trail ,but when i stretch the the data ,startools finds it so i just didn't use those subs turned into too much trouble .

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