Share:

We have updated the forum software 🙂 ! We are now working on upgrading the whole site and the Forum to a dark theme...  so please refresh your internet browser twice to properly update the forum appearance AND functionality... Check your internet browser for the refresh function, on windows, this usually is the F5 button, but it depends on your internet browser.

Bad Pixel Map  

Page 2 / 2
  RSS

 Heno
(@heno)
White Dwarf Customer
Joined: 1 year ago
Posts: 17
October 22, 2017 17:45  

Hi Mabula.

No reason for apologies. I'm sure you are a busy man.
I'm just glad that it isn't me that's fishy. 🙂
Take your time. I have my BPM made from 3 darks. That will do fine for now I'm sure.

Helge.


ReplyQuote
(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2070
October 22, 2017 17:49  

Hi Helge,

thanks 😉

The problem is quite clear, I'll do a test with my Nikon D610 which is quite similar.. should know more later today...

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


ReplyQuote
(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2070
October 22, 2017 18:32  

Hi Helge,

I have found the problem.

I was using a noise calculation approach that was a problem with such a low amount of noise. A have changed the noise calculation to MSR gaussian noise and now it perfectly works with 6 darks.

So this will be fixed in the next APP version.

I do think that the BPM that you currently have based on only 2 darks should work pretty good.

But please check this BPM, this one is based on your 6 darks that you sent me with a hot pixel kappa of 2, nearly 1% hot pixels found now:

Thank you for sharing this problem 😉

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


ReplyQuote
(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2070
October 22, 2017 20:15  
Posted by: Heno

 

One suggestion: I would have liked to see the number of darks used (and flats if included) in the details of the PBM.  Now I have to remember which BPM was created from which (number of) files.

Best regards

Helge

Hi Helge,

I have added this the FITS metadata 😉

FITS HDUs: 1
HDU1 - SIMPLE  =                    T / Java FITS: Sun Oct 22 20:09:49 CEST 2017      
HDU1 - BITPIX  =                    8 / bits per data value                           
HDU1 - NAXIS   =                    2 / number of axes                                
HDU1 - NAXIS1  =                 6032 / size of the n'th axis                         
HDU1 - NAXIS2  =                 4032 / size of the n'th axis                         
HDU1 - EXTEND  =                    T / Extensions are permitted                      
HDU1 - DATE    = '2017-10-22T18:09:49' / creation date of bad pixel map               
HDU1 - SOFTWARE= 'Astro Pixel Processor by Aries Productions' / software              
HDU1 - VERSION = '1.054   '           / Astro Pixel Processor version                 
HDU1 - CALFRAME= 'bad pixel map'      / bad pixel map for instrument NIKON D750       
HDU1 - INSTRUME= 'NIKON D750'         / instrument name                               
HDU1 - CFAIMAGE= 'no      '           / Color Filter Array pattern                    
HDU1 - NPIX    =             24321024 / raw number of pixels                          
HDU1 - HOTKAPPA= '2,00    '           / kappa value used for hot pixel determination  
HDU1 - COLDFRAC= '0,50    '           / percentage used for cold pixel determination  
HDU1 - NBADPIX =               201827 / number of bad pixels                          
HDU1 - PBADPIX = '0,830   '           / percentage of bad pixels                      
HDU1 - NHOTPIX =               201827 / number of hot pixels                          
HDU1 - PHOTPIX = '0,830   '           / percentage of hot pixels                      
HDU1 - NCOLDPIX=                    0 / number of cold pixels                         
HDU1 - PCOLDPIX= '0,000   '           / percentage of cold pixels                     
HDU1 - NLINPIX =             24119197 / number of linear pixels                       
HDU1 - PLINPIX = '99,170  '           / percentage of linear pixels                   
HDU1 - NUMDARKS=                    6 / # of dark frames used in creation of the BPM  
HDU1 - NUMFLATS=                    0 / # of flat frames used in creation of the BPM  
HDU1 - END                                                                            

This is the BPM:

Kind regards,

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


xsnrg liked
ReplyQuote
 Heno
(@heno)
White Dwarf Customer
Joined: 1 year ago
Posts: 17
October 23, 2017 09:25  

Hi Mabula

Thanks for the BPM and thanks for solving the issue so quickly.
It is really cool to see ones proposal being adopted, even a small one like this. 😉

Clear skies

Helge

 


ReplyQuote
(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2070
October 25, 2017 23:27  

You're most welcome Helge 😉

Main developer of Astro Pixel Processor and owner of Aries Productions


ReplyQuote
Page 2 / 2
Share: