Liam,

The RIDES protocol begins as soon as you clamp the leaf.

The protocol uses the open/close start feature, which uses a magnet and hall effect sensor in the upper and lower parts of the jaw to sense when the clamp opens and closes. For RIDES the protocol goes like this:

1. Hit Take Measurement in the mobile app
2. As soon as the clamp opens, the protocol will measure the ambient light and shine a corresponding actinic light in the measurement chamber.
3. As soon as the clamp closes again (hopefully over a leaf), the protocol begins.

If everything is working properly, the measurement will take ~15 seconds, from when you closed the clamp on the leaf.

Great, thank you!

Hey Dan,

My RIDES measurement seem to be taking around 35 seconds to complete for some reason. Any cause for concern?

Thanks, Liam

Liam,

If the measurement is taking longer than 20 seconds, that is usually a sign that the MultispeQ is not properly recognizing when the clamp is either opened or closed. It is easy to test if the MultispeQ is reading that clamp is open, if a red actinic light turns on in the chamber when you open the clamp (after hitting Take Measurement) then it is reading the open position properly. Hold the clamp open for a second or two to see if the light is turning on. If the light is turning on, then your measurement quality will be good, despite the delay, because the leaf conditions are not changing (i.e. no dark period between hitting Take Measurement and the measurement running).

If you think the MultispeQ is not properly recognizing the open or closed, you can reset the "Open" and "Closed" positions using the console in the desktop app. To do this, go to the Settings tab in the desktop app. Select the Console. Enter the command "set_open_closed_positions" and hit enter. Then, following the instructions, hold the clamp open to the position that you want set as the closed position (this should be a little bit wider than the thickest leaf you will measure, so that the MultispeQ will recognize that the clamp is closed even if you have a thick leaf). Then follow the same procedure for the "Open" position.

Important note the "set_open_closed_positions" command only works for Firmware versions 1.23 and later.

Hi Dan,

Thank you. That really seems to have helped. Now measurement times are around 15 seconds. I guess this means that all of the data that I have collected so far may not be very trustworthy. Even still, I'm glad that I asked! Thanks, as always for your help.

Liam

Hi Dan,

I actually seem to be having another issue. After doing the reset on the open and closed setting, I took a couple of measurements. While the speed of the measurement dropped significantly, it seems that some of the measurements may be off. Specifically, leaf temperature differential all of a sudden went from a typical reading of around -2 all the way to around -8, and in one case -10.

What do you think is going on here?

Liam

Hi Liam,

it is a bit hard to tell remotely what is going on. I checked one of your measurements (https://photosynq.org/projects/3772/explore/811446) and you can tell that the Leaf Temperature Differential is calculated correctly. If you want to check your instrument you can use the command all_sensors in the console, to get continuos readings from the sensors in your instrument. Look out for the word "contactless_temp". When you clamp your finger the temperature should be around 36. That should confirm the contactless sensor works. You can stop the output by using the command -1+.

Since there was no project description, I'm not able to tell what the measurement conditions are. Based on the title I assume, you are using a mask to look at smaller leaves. Make sure the leaf is actually covering the contactless temperature sensor and you are not measuring the temperature of the clamp/mask.

Hope this helps...