EOS1000D EXIF temperature never registers 17, 19, 22 or 23C!

[BrendanC]

I'm building up a library of darks, flat darks and bias calibration frames, so that I have a set for each temperature. It gives me an enormous sense of well-being.

I've just been through them all and noticed something strange.

Of the hundreds of frames I must have taken over the past few days, none of them have been at 17, 19, 22 or 23C!

Not a single one.

I've noticed that the EXIF temperature can seem to skip a degree or two from time to time, but didn't realise it was always skipping the same temperatures.

So I just checked the many thousands of raw files I have in the archive. Again, none at 17, 19, 22 or 23C!

Is this... normal? It's beyond coincidence or a fluke, at that many frames.

I guess it doesn't matter, I can still match calibration frames to light frames. I just seems a bit oddddddddd.

[almcl]

Using a different Canon (700d) I just checked my dark library for ISO 1600, 180 seconds and found every temperature from 1°C to 32°C, no gaps, although this may not be very helpful as it's a different sensor and processor.

What software are you using to extract the EXIF data?  Might this have a bearing on the figures?

[BrendanC]

I guess it might. I'm using Astrophotography Tool, APT.

[almcl]

Interesting. 

The figures in my list above are the APT reported temperatures, I've just checked to see whether Exiflog gives the same answer and, perhaps not surprisingly, it does, which doesn't get us any further forward, sorry!

 

[michael8554]

2 hours ago, BrendanC said:

It gives me an enormous sense of well-being.

Park Life  ? "It gives me a sense of enormous well-being"

Michael

Edited June 9, 2020 by michael8554

[JamesF]

4 minutes ago, michael8554 said:

Park Life  ? "It gives me a sense of enormous well-being"

Michael

Been feeding the pigeons and sparrows again? :)

James

[BrendanC]

Yep, Park Life. I never really liked Blur but I do like that line...! 

[Adam J]

On 09/06/2020 at 20:54, BrendanC said:

I'm building up a library of darks, flat darks and bias calibration frames, so that I have a set for each temperature. It gives me an enormous sense of well-being.

I've just been through them all and noticed something strange.

Of the hundreds of frames I must have taken over the past few days, none of them have been at 17, 19, 22 or 23C!

Not a single one.

I've noticed that the EXIF temperature can seem to skip a degree or two from time to time, but didn't realise it was always skipping the same temperatures.

So I just checked the many thousands of raw files I have in the archive. Again, none at 17, 19, 22 or 23C!

Is this... normal? It's beyond coincidence or a fluke, at that many frames.

I guess it doesn't matter, I can still match calibration frames to light frames. I just seems a bit oddddddddd.

Relax the 1000D temperature sensor is not as accurate as the more recent models and the A/D is not able to produce all values, hence sometimes it skips a little.

Mine used to do it too.

Adam

[BrendanC]

Thanks. I figured it wasn't a real problem. Just oddddddddddd.