Also, the specification page says the latest device can measure "leaf angle and leaf direction" but how does it do this? I thought the sensor only clamps down on a small portion of the leaf?

Hey Saket - thanks for the good questions -->

1. No leaf thickness on the beta or v1.0 MultispeQs :( . We do have a device which measures leaf thickness, but we weren't able to translate it into the new MultispeQ because there's so much stuff packed into the clamp (leds, detectors, IR sensor, etc.). The issue was actually with identifying a spring mechanism for keeping constant tension on the bottom of the leaf, which proved too difficult to source. It's a real bummer because the sensor works extremely well, and I really wanted to include it. It's still possible that by some stroke of luck we find the right part in the next 2 seeks we can make it work, but it's unlikely. Sorry about that.

2. The leaf angle and direction sensors are measured using a magnetometer and accelerometer located in the MultispeQ itself. So when you clamp the leaf with the device, if you clamp it consistently at 90 degrees from the leaf's main axis and you don't move the leaf from it's native position (ie leave it in it's normal position on the plant), the magnetometer will measure the cardinal direction of the leaf and the accelerometer will measure the tilt relative to the ground plane. Of course if you take the leaf and move it from it's native position, those values will not be correct, so getting good direction/tilt values depends on proper clamping. Does that make sense? It's much easier to show than explain, but I hope that helps.

3. There are many many protocols, most of which are for testing, or for users with modified devices (lots of ones for algae MultispeQs or CoralspeQ for example). There's really only a few which get used most of the time - that's The One v3.0 and Chlorophyll Content (SPAD) III . Those are the workhorse protocols of the MultispeQ and I'd suggest using them IN THAT ORDER (order does impact the quality of the measurement). When we release the MultispeQ V1.0 we're going to really clean up the protocol list so it's not so confusing, and so users see the protocols which are actually relevant to them. So I apologize for the confusion during the beta, but appreciate the feedback as it helps our development process make things better!

It is unfortunate, that there is no measurement of the thickness of the leaves. Informative indicators.

Agreed, it sucks, but we do actually have a pretty sweet little tool for measuring thickness. I included a picture just so you could see it. I hope one day to get this integrated into the MultispeQ, but alas Spring came up too fast. Sorry guys, we're in a race against time -