Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

PixInsight - Warning Message WBPP Scrip - No master dark matching the exposure has been found

astrophotography dslr
  • Please log in to reply
5 replies to this topic

#1 Jim Waters

Jim Waters

    Gemini

  • *****
  • topic starter
  • Posts: 3,207
  • Joined: 21 Oct 2007
  • Loc: Phoenix, AZ USA

Posted 17 November 2019 - 12:59 PM

What's the significance of this warning message?  Are Darks used to process the integrated subs?  I take my Darks after I am done with my Lights.

 

This is part of the log file from the new Weighted Batch PreProcessing (WBPP) script.

 

------------

 

*** Warning: Flat frames will be calibrated only with master bias -- no master dark matching the exposure has been found
[Calibration data]
Master bias: C:/Users/JTWaters/Desktop/master/masterBias-BINNING_1.xisf
Master dark: none
Master flat: none
*** Warning: Flat frames will be calibrated only with master bias -- no master dark matching the exposure has been found
[Calibration data]
Master bias: C:/Users/JTWaters/Desktop/master/masterBias-BINNING_1.xisf
Master dark: none
Master flat: none



#2 pfile

pfile

    Fly Me to the Moon

  • -----
  • Posts: 5,296
  • Joined: 14 Jun 2009

Posted 17 November 2019 - 02:17 PM

well it's saying that it could not find a good match between whatever darks are loaded and the flats. so it's telling you it's going to calibrate the flats with the master bias. depending on the camera and the length of the flat exposures, this is fine. for instance with my 8300M and light panel, my flats are no more than 5s long, and so calibrating the flats with a master bias is OK.

 

rob



#3 Jim Waters

Jim Waters

    Gemini

  • *****
  • topic starter
  • Posts: 3,207
  • Joined: 21 Oct 2007
  • Loc: Phoenix, AZ USA

Posted 17 November 2019 - 02:24 PM

Thanks Rob.  I am using a Canon 6D.  Light and Dark subs range from 60 to 420 seconds.  Flats are usually 1/10 of a second.

 

Is there a way to override this or force Darks to be used? 



#4 Charlie B

Charlie B

    Apollo

  • -----
  • Posts: 1,461
  • Joined: 22 Mar 2008
  • Loc: Sterling, Virginia

Posted 17 November 2019 - 06:55 PM

Thanks Rob.  I am using a Canon 6D.  Light and Dark subs range from 60 to 420 seconds.  Flats are usually 1/10 of a second.

 

Is there a way to override this or force Darks to be used? 

Flat darks are not too far  (1/1000) from your 1/10s flat darks.  However,  take flat darks and the process should create a master of the correct exposure,  if exptime can differentiate that fine.

Regards 

Charlie  B



#5 sharkmelley

sharkmelley

    Mercury-Atlas

  • *****
  • Posts: 2,530
  • Joined: 19 Feb 2013

Posted 18 November 2019 - 02:23 AM

Thanks Rob.  I am using a Canon 6D.  Light and Dark subs range from 60 to 420 seconds.  Flats are usually 1/10 of a second.

 

Is there a way to override this or force Darks to be used? 

You don't want the flats to be calibrated with your darks because the exposure times of the darks you have are nowhere near matching your flats, creating a dark current mismatch.  The software has done the right thing by using bias instead.

 

Note that the darks will still be used for your lights (unless of course you see similar messages during the calibration of your lights).

 

Mark


Edited by sharkmelley, 18 November 2019 - 04:49 AM.

  • pfile and bobzeq25 like this

#6 maxmir

maxmir

    Ranger 4

  • ***--
  • Posts: 318
  • Joined: 03 Oct 2005

Posted 18 November 2019 - 03:44 AM

I always use bias for flats.  I can't see how less than a electron of dark current is going to have an impact.

If my NB flats were taking over 20-30sec I might think about it


  • pfile and sharkmelley like this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: astrophotography, dslr



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics