Press blank to take a dark and blank reading, press sample to take a sample reading. You can change the wavelength from the wavelength screen, see below.
There is also a USB logging function that will log each sample to a file called photometrics.csv on an USB memory stick. Makesure you insert a USB stick before turning on logging and that when you finish, you turn off logging and unmount the drive (see my earlier post about removing USB sticks).
The wavelength screen has been revamped, there are now 2 presets for the stray light test.
The alignment screen is similar to he 73's alignment screen and has been designed for a engineer to aligned the optics.
The CALIBRATE ENDSTOP button will find the 0nm (white band) and store it in the PCB.
See the release notes for further details