I recently received one of these meters, did some testing, corresponded with the guy to verify my observations, and sent it back.
While I appreciate anyone who is supporting the film community, this meter is simply not usable.
First the pros. The small size is perfect for mounting on an accessory shoe. The display is bright and easy to read, even in sunlight. The buttons are intuitive and user friendly. Best of all is the replaceable button cell, so you don't have to futz with a USB cable and recharging.
Now the cons, which make it unusable to anyone who needs an accurate meter. The meter locks in a single reading when turned on. Where ever it happens to be pointing when you hit the button is the reading you get. So if it is shoe mounted and you turn it on and bring the camera up to your eye to frame, you've got the wrong exposure. That wrong exposure stays in the display until you manage to find the tiny power button while still trying to keep the image framed, then turn the meter off and on again. I've never seen any other meter that works like this, and for good reason.
Worse than that is that it only reads in one stop increments. Being off a full stop will ruin any transparency, which is the primary application for a meter. In order to "compensate" for this screaming shortcoming, the meter can be set to flash an EV value in 1/10 stop increments. "Flash" is a bit of an overstatement. The value literally displays for about 1/4 second. During this time you need to read and remember the decimal value, then do the mental arithmetic to apply that correction to the full stop meter reading to get an accurate exposure.
And after spending a significant chunk of change in postage both ways, the most upsetting part is that these shortcomings could be easily fixed. A simple software change would allow the meter reading to be dynamic, like every other light meter in the world. The meter obviously has the sensitivity to measure in 1/3 stop increments, the guy just chose not to do so.. I made these recommendations to the manufacturer and he made it clear that he has no interest in making any changes (He "doesn't want to confuse beginners".) . Since he isn't up front about these shortcomings, I hope this posting is helpful to anyone contemplating a purchase.
P.S.: I have a V-201X meter from China, which does read dynamically so you get the actual exposure where ever it is pointed. It also reads in third stops for the aperture, third stops for the shutter speed and tenth stops for the EV. It's cheaper than the Reveni, to boot. It is a bit larger and has to be recharged via USB, but I'll take that for a meter that's actually useful.
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