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INDI Library v1.7.9 Released (23 Jun 2019)

INDI Library v1.7.9 is mostly a maintenance release to fix a few bugs in several drivers.

Tempereature in DSLR subs?

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Tempereature in DSLR subs? was created by mlarsson

Hi!

I'm curious about the temperature data in DSLR subs. When I download subs from my Canon 1000D, there is a FITS keyword CCD-temp, filled in with a temperature. WHen I download CR2-files, the raw files, I cannot find any information about temperature in the EXIF-tags of the images.

So where does the FITS-keyword information on temperature come from? My belief was that the fits-files were converted form the cr2-files - and if the cr2-files do not contain information about temperature, where then does it come from? Or do the CR2-files contain this information, but I just cannot find it?

Magnus

C8, Losmandy G11, Canon 1000D astromodified.
5 months 2 weeks ago #33566

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Replied by Copello on topic Tempereature in DSLR subs?

Hi Magnus,

the (sensor) temperature is embedded in the raw DSLR format. Try e.g.
>exiftool IMG_8327.CR2 | grep Tem
Camera Temperature              : 28 C
Color Temperature               : 5200
Color Temp As Shot              : 5200
Color Temp Auto                 : 5200
Color Temp Measured             : 5200
Color Temp Daylight             : 5200
Color Temp Shade                : 7000
Color Temp Cloudy               : 6000
Color Temp Tungsten             : 3200
Color Temp Fluorescent          : 3720
Color Temp Kelvin               : 5200
Color Temp Flash                : 6277

The gphoto2 driver uses LibRaw to unpack the raw DSLR and uses exactly these EXIF information to read out the temperatures:
if (lib_raw.imgdata.other.SensorTemperature > -273.15f)
                gphoto->last_sensor_temp = lib_raw.imgdata.other.SensorTemperature;
            else if (lib_raw.imgdata.other.CameraTemperature > -273.15f)
                gphoto->last_sensor_temp = lib_raw.imgdata.other.CameraTemperature;
The following user(s) said Thank You: mlarsson
5 months 2 weeks ago #33568

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Replied by mlarsson on topic Tempereature in DSLR subs?

Ah, wow, great!! Thanks!

Magnus

C8, Losmandy G11, Canon 1000D astromodified.
5 months 2 weeks ago #33569

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