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|ID||Project||Category||View Status||Date Submitted||Last Update|
|0002141||CCdciel||[All Projects] General||public||19-06-12 14:11||19-06-15 08:45|
|Reporter||han||Assigned To||Patrick Chevalley|
|Priority||low||Severity||tweak||Reproducibility||have not tried|
|Target Version||1.0||Fixed in Version|
|Summary||0002141: Fits header comments for GAIN and default camera settings.|
|Description||1) The camera gain is recorded in the FITS header as follows:|
GAIN = 139 / Video gain
is it not better to change the comments in something like:
GAIN = 139 / Camera gain
I noted that Diffraction limited is using EGAIN and at the INDI forum found that "Nebulosity uses GAIN whereas Ekos is using EPERADU". So no standard again.
2) I like the new camera option "Gain from camera driver" since I always use unity gain. Is it not better to have this option default checked?. Simplifies the menu for new users and prevents wrong inconsistent gain setting.
|Tags||No tags attached.|
1) I voluntarily use "video gain" to avoid confusion with the gain of the camera in photoelectrons per ADU.
Sure the video gain setting is related to the "electrons per ADU" but is given in arbitrary unit unique to every camera model.
For the ASI1660 "video gain"=139 is equivalent to "electrons per ADU"=1 but this is different for other camera.
But I can add a header for EGAIN if available from the driver, this is the ASCOM property ElectronsPerADU. I not see an INDI equivalent in the documentation but I will look at the different driver source code.
EGAIN is the standard keyword defined in the SBIG Fits Extension everyone is using now.
2) It is set by default for a new installation of the program or if you create a new device profile (not copy).
But for existing profile I prefer to not change the old behavior, to not break some user setting that rely on changing the gain.
After a quick look in the INDI code the keyword EPERADU is only implemented for QSI camera.
The ASI driver define a variable ElecPerADU but it is not used anywhere.
So I will probably implement that only for ASCOM.
I would not add any new keyword. GAIN is fine for me
SBIG is now owned by Diffraction Limited (Maxim DL) and they publish their keywords at:
and they specify:
EGAIN – electronic gain in photoelectrons per ADU.
That doesn't match with the ZWO 0.1 db specification so my 139=unity gain.
I personally would stick with "GAIN" like Nebulosity. I assume it is only read by Humans. Maybe you should write at the comments something like
GAIN = 139 / Camera gain setting in units as specified by manufacturer.
OK I keep only this Gain keyword and updated the comment with your text that give a better description. I only have to shorten the text to "Camera gain setting in manufacturer units" to fit the 80 column header.
|19-06-12 14:11||han||New Issue|
|19-06-14 21:44||Patrick Chevalley||Assigned To||=> Patrick Chevalley|
|19-06-14 21:44||Patrick Chevalley||Status||new => assigned|
|19-06-14 21:44||Patrick Chevalley||Description Updated||View Revisions|
|19-06-14 21:44||Patrick Chevalley||Steps to Reproduce Updated||View Revisions|
|19-06-14 21:45||Patrick Chevalley||Steps to Reproduce Updated||View Revisions|
|19-06-14 21:45||Patrick Chevalley||Note Added: 0005691|
|19-06-14 21:58||Patrick Chevalley||Note Added: 0005692|
|19-06-14 22:14||han||Note Added: 0005693|
|19-06-15 08:45||Patrick Chevalley||Status||assigned => resolved|
|19-06-15 08:45||Patrick Chevalley||Resolution||open => fixed|
|19-06-15 08:45||Patrick Chevalley||Target Version||=> 1.0|
|19-06-15 08:45||Patrick Chevalley||Note Added: 0005695|