What is the temperature range for work device? I want to make the study of photosynthesis in winter.
You should be able to collect photosynthesis data in the winter. However, in the cooler weather the LED's will cool down more than at normal temperature ranges. This may have an impact on light intensities. This might be a problem for the actinic light, but maybe not. The best way to check would be too look at the Fs portions of the flouresence curves. If the Fs curve is sloped, then the actinic light is probably not accurately reflecting the actual light conditions. If Fs is flat, then you should have no problem.
The temperature sensor is working incorrectly. Measurements carried out on the street 2-4 degrees. The device showed 17-20 degrees. Maybe the reason is the transition from warm to cold room. It takes time to normalize the indicators?
Hey Andriy - yes we know the temp sensor is notoriously off... it heats up in your hand a lot, and heats up from solar radiation because the case itself is black. In addition, the case and circuit board will take several minutes to adjust temperature from going inside to outside. Finally, the circuit board power supply is quite inefficient so there's lots of heat generated inside the case.
The next version we're trying to address lots of these issues - making the case white, improving the heat transfer away from your case from your hand, and putting the temperature sensor further out on the circuit board where it will adjust to the actual outdoor temp faster. In addition, the power supply is waaaaay more efficient, so hopefully the board itself will generate less heat.
You can test if the calibrated sensor is truly off by placing the device outside for 10 - 15 minutes (without holding it) and take a measurement. See if that's closer -