Author Topic: Unofficial documentation for ImageCalibration  (Read 3893 times)

Offline bitli

  • PTeam Member
  • PixInsight Guru
  • ****
  • Posts: 508
    • View Profile
Unofficial documentation for ImageCalibration
« on: 2014 May 31 12:42:57 »
Tired of waiting for documentation I attempted to write one for ImageCalibration. It is attached here in two formats: The original pidoc and the generated html. You can regenerate the documentation from the pidoc sources or simply unzip the html in the directory C:\Program Files\PixInsight\doc\tools or equivalent (this may require administrator privilege).

BEWARE: I copied and adapted some text from other documents and from the tooltips (the copyright is assigned to Pleiades Astrophoto, so I hope they do not mind). I also wrote some parts myself and inserted information I found in the source file.  I hope that it is correct, but it may contains errors.  Also I am at an astronomical distance of having the talent of Juan for documentation, however I hope that it is better than nothing.

You can post suggestions or corrections in this thread, I will update the attached files as time permits.  Is somebody is willing to correct the English in the pidoc source, I would be very grateful.

-- bitli


Offline georg.viehoever

  • PTeam Member
  • PixInsight Jedi Master
  • ******
  • Posts: 2131
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #1 on: 2014 June 02 03:19:22 »
I love that you are trying to do this :) .

At the same time, against all experience, I am still hoping to get decent documentation from the development team... :'(

Georg
Georg (6 inch Newton, unmodified Canon EOS40D+80D, unguided EQ5 mount)

Offline Philippe B.

  • PixInsight Old Hand
  • ****
  • Posts: 388
    • View Profile
    • CIEL AUSTRAL
Re: Unofficial documentation for ImageCalibration
« Reply #2 on: 2014 June 03 00:21:55 »
Hi Jean-Marc


Very nice job  8)


You are now ready to make all Pixinsight documentation !!!!  >:D
Juan could hire you for this  :tongue:




Offline Juan Conejero

  • PTeam Member
  • PixInsight Jedi Grand Master
  • ********
  • Posts: 6795
    • View Profile
    • http://pixinsight.com/
Re: Unofficial documentation for ImageCalibration
« Reply #3 on: 2014 June 03 01:38:20 »
Jean-Marc,

Great job. Let me "digest" this before answering. You're taking a serious risk with this initiative...  >:D
Juan Conejero
PixInsight Development Team
http://pixinsight.com/

Offline bitli

  • PTeam Member
  • PixInsight Guru
  • ****
  • Posts: 508
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #4 on: 2014 June 03 02:15:47 »
From georg:
Quote
I am still hoping to get decent documentation from the development team.
The problem is they do not do decent documentation, only outstanding documentation - or none at all.  I just think that half decent may be good enough some times... We'll see

From Philippe:
Quote
You are now ready to make all Pixinsight documentation !!!!
well, I retire in a few years, maybe if the doc is not finished by that time  ;)

From Juan
Quote
You're taking a serious risk with this initiative...
You are taking serious risk in trying to digest it  ;)

-- bitli

Offline jerryyyyy

  • PixInsight Old Hand
  • ****
  • Posts: 419
    • View Profile
    • Astrobin Images
Re: Unofficial documentation for ImageCalibration
« Reply #5 on: 2014 June 03 08:21:21 »
Thanks, this is great stuff to read on a plane.  I wonder if you can help lazy novices like me with one question.  In the BatchPreprocessing Script if you start with raw bias darks and flats etc, BPP will create masters.  I sorta discovered this by chance and it seems to cut down a lot of effort.... but am I missing something and getting less than optimal results? 
Takahashi 180ED
Astrophysics Mach1
SBIG STT-8300M and Nikon D800
PixInsight Maxim DL 6 CCDComander TheSkyX FocusMax

Offline georg.viehoever

  • PTeam Member
  • PixInsight Jedi Master
  • ******
  • Posts: 2131
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #6 on: 2014 June 03 10:29:53 »
...
From Philippe:
Quote
You are now ready to make all Pixinsight documentation !!!!
well, I retire in a few years, maybe if the doc is not finished by that time  ;)
...

You probably just created a retirement employment opportunity for yourself  ;)
Georg (6 inch Newton, unmodified Canon EOS40D+80D, unguided EQ5 mount)

Offline Geoff

  • PixInsight Padawan
  • ****
  • Posts: 883
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #7 on: 2014 June 17 18:09:49 »
Very nice Jean-Marc.  Only another 61 to go.
Geoff
Don't panic! (Douglas Adams)
Astrobin page at http://www.astrobin.com/users/Geoff/
Webpage (under construction) http://geoffsastro.smugmug.com/

Offline mads0100

  • PixInsight Addict
  • ***
  • Posts: 116
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #8 on: 2014 June 22 17:34:10 »
Jerome,

    I found that using the BPP is giving me poorer results than doing it manually.  Specifically with my flats.

Offline bitli

  • PTeam Member
  • PixInsight Guru
  • ****
  • Posts: 508
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #9 on: 2014 June 23 04:11:01 »
BPP tends to "calibrate" the flat with the image darks (at least it did a couple of weeks ago).

You may want to look at the process of BPP (using the log) and try to apply exactly the same manually.  It should give exactly the same result (pixel to pixel) at least as far as calibration is concerned (SA has some statistic in the algorithm).  Try on a small set of images, this is just to understand what happens.

If it doesn't give the same result, then you did not yet found what BPP is doing.

There is no magic in BPP and no image related intelligence, it is "just" a pretty clever way to sequence a set of standard PI operations.  Clever but sometime surprising.

-- bitli

Offline mads0100

  • PixInsight Addict
  • ***
  • Posts: 116
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #10 on: 2014 June 23 06:39:36 »
I found that I couldn't use the same settings in BPP as I could manually, specifically for integration.  For instance, you can't set 'equalize fluxes' for your flats.  Unless that's behind the scenes?

Offline jkmorse

  • PixInsight Padawan
  • ****
  • Posts: 916
  • Two questions, Mitch . .
    • View Profile
    • Jim Morse Astronomy
Re: Unofficial documentation for ImageCalibration
« Reply #11 on: 2014 June 23 15:06:51 »
Bitli,

Great stuff!!  I can't wait to dig into your suggestions and play with this since ImageCalibration is one of the most important but least documented parts of PI. 

Thanks for a great effort.

Jim
Really, are clear skies, low wind and no moon that much to ask for? 

New Mexico Skies Observatory
FLI Microline 16803
Planewave CDK17 - Paramount MEII
Planewave IFR90 - Astrodon LRGB & NB filters
SkyX - MaximDL - ACP

http://www.jimmorse-astronomy.com
http://www.astrobin.com/users/JimMors

Offline bitli

  • PTeam Member
  • PixInsight Guru
  • ****
  • Posts: 508
    • View Profile
Re: Unofficial documentation for ImageCalibration
« Reply #12 on: 2014 June 24 03:28:17 »
mads0100, your are right, the BPP script does not allow you to set all options that you can set manually.  The other way is always possible (you can do manually what was done with BPP).
Unfortunately the only (but instructive) way to find what BPP is doing is to read the sources, although the logs provide good information too.
-- bitli