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  #11  
Old 9th February 2021, 09:58 PM
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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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Old 10th February 2021, 12:42 PM
Mike O'Pray Mike O'Pray is offline
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Bob, is this what you are referring to: " how does one make sure they are metering exactly the spot they want though? With an optical meter, of course you just place the dot on the spot you like, but this meter doesn't have optics, so is there a possibility than the meter's axis would be misaligned with respect to one's sightline, resulting in metering the wrong spot? Basically, if I am metering for a tree trunk, can I be sure that I am metering for the tree trunk and not the grass next to it?"

The above quote was from one of the questions/comments on the Todd Korol video review of the Reveni spot. This was addressed directly to Matt Bechberger the inventor but as yet he hasn't answered that one

He did answer another question that may or may not be related to your concern which was along the lines of what stops you eye wandering over the scene and thus the brain tries to impose the spot over the bit of the scene your eye last wandered over rather than the actual spot chosen.

The answer to this from Matt Bechberger appears to be that your eye has only the spot as its target and remains on this while the other eye looks at the whole scene but the brain obeys the aimed eye and transposes the whole scene to align the spot with the area in the scene that the brain has already fixed upon

Todd Korol the reviewer said that he had no problem with the "wandering eye " syndrome so it wasn't a problem for him

Anyway I agree that this superimposing action of a person's vision into an otherwise black non optical screen is a sufficiently novel concept that I'd have expected more of these kind of questions to be asked and Matt Bechberger to have asked himself the question of what part of his invention is likely to draw the most concern so that a full explanation would have been available

Mike
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Old 10th February 2021, 12:53 PM
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Quote:
Originally Posted by Mike O'Pray View Post
Bob, is this what you are referring to: " how does one make sure they are metering exactly the spot they want though? With an optical meter, of course you just place the dot on the spot you like, but this meter doesn't have optics, so is there a possibility than the meter's axis would be misaligned with respect to one's sightline, resulting in metering the wrong spot? Basically, if I am metering for a tree trunk, can I be sure that I am metering for the tree trunk and not the grass next to it?"
...
Mike
Yep - your quote exactly reflects my concern. It will be interesting to see if the query gets an answer.

The wondering eye thing I can sort of see being OK - when playing with my mock-up if seemed that you do indeed adjust the "meter" to be over the same spot as your other eye is looking. But again, I'm not sure if that is accurate enough to keep a 1 degree angle aligned and even if so, is the meter axis aligned as per the first quote?

I suspect the only answer is to either try it oneself or see a more detailed review that takes these potential issues into consideration. If it does indeed work, it's a great idea.
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Old 10th February 2021, 03:02 PM
Mike O'Pray Mike O'Pray is offline
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Quote:
Originally Posted by Bob View Post
Yep - your quote exactly reflects my concern. It will be interesting to see if the query gets an answer.

I suspect the only answer is to either try it oneself or see a more detailed review that takes these potential issues into consideration. If it does indeed work, it's a great idea.
That about sums up my sentiments as well, Bob

Mike
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