The acceptance angle of the LISST-100X / LISST-STX transmission measurement differs between instruments:

IN AIR, the LISST-100X type C has an acceptance angle of 0.0177 degrees while a type B has an acceptance angle of 0.0353 degrees.

The discontinued LISST-FLOC had an acceptance angle of 0.0058 degrees.

The IN WATER values goes as 1/n, where n is the refractive index of seawater at 670nm (1.34). The IN WATER acceptance angle is therefore 0.0132 degrees for a type C. The IN WATER acceptance angles are 0.0263 degrees for a type B and 0.0043 degrees for the discontinued LISST-FLOC. The scattering angles for the 32 rings that are published in the LISST manual are the IN AIR values. They should be divided by the refractive index in order to obtain the IN WATER values.

For an updated list of acceptance angles of Sequoia’s sensors, see our article published here.