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Old 9th February 2021, 09:58 PM
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Bob Bob is offline
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Hold something roughly the size of the meter in front of one eye - the plastic canister from a 35mm film or similar. Tape a piece of paper on the end facing your eye with a dot in the centre to represent the screen. Now hold it up to your eye (it will be out of focus but that does not matter) and put the dot at a desired point on the wall or something out the window, overlaying the view from your other eye. This is the intended mode of operation of the meter.

You now have to ensure that the canister's long axis is also pointing at the same place or the light measuring sensor will not be pointing at it. How? - you have no reference to do that. You can put the dot where you are looking but you don't know if the canister itself is pointing at the same place. You can easily deliberately point the canister so that the far end is pointing many degrees away from the place you selected on the wall or tree trunk outside and still have the dot over the place you first selected but clearly, the "meter" will be pointing somewhere quite different.

Now, I think normal eye/hand coordination will get you close - you can sense if it is fairly straight, but I can't see that working down to under 1 degree. Now, I may be wrong - there may be something about it that makes you adjust your hand to make it all line up, but I can't replicate that using a mock-up like the above.

Last edited by Bob; 9th February 2021 at 10:16 PM.
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