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Quick Calibration Question - Thoughts Please

For discussion of DIY weather equipment - sensors, accessories, improvements to existing kit etc
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baylisj
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Quick Calibration Question - Thoughts Please

Post by baylisj »

I currently have a VP2 on the roof and a Vue in the garden.

I have been monitoring their readings for a week now (rainfall has been spot on, exactly the same even in very windy conditions and the Vue is sheltered). The Vue is 2m off the ground.

There is about 0.6'C difference (Vue lower) between the temps during the day and night and if the skies are clear there's about 1.2'C between them.

We all know that you shouldn't really be taking the temp above the roof and the 2m location is more accurate. So, since the Vue is going soon, off to my parents' house do I

a) Leave the VP2 alone
b) Calibrate the VP2 temp so it's more accurate. Probably by -0.8'C.

I used to have the Vue on the roof for 2 years so have weather records since then. Just thinking if I calibrate then the records are off straight away if you know what I mean.

Would welcome your thoughts/comments.

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Jon
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beteljuice
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Re: Quick Calibration Question - Thoughts Please

Post by beteljuice »

The old joke about the man with two thermometers ...

If that level of accuracy is important to you, then yes having now got a 'reference' tweak the roof mounted kit (or Cumulus offset) -0.8 deg.

If you are happy with all your historic data being held in Cumulus, then get hacking with a spreadsheet, but I personally would probably leave the 'old' readings high.
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mcrossley
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Re: Quick Calibration Question - Thoughts Please

Post by mcrossley »

Except an offset is probably only valid if there is no or little wind? How do you know the Vue is right and the VP2 wrong?
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