Used for photography with infrared films.
R72 passes only infrared rays above 720nm.
RM90 passes only that above 900nm.
Often used in crime detection, medical photography, detection of distribution of vegetation, etc.
Reviewed by 1 customers
Not a lot to say. Usual high Hoya quality. Does what it's supposed to do. I use it with Ilford SFX and Rollei IR film. Only problem and this is NOT the fault of design or build is that R72 filter are so dark that you have to compose & focus and then put the filter on. You will REALLY surprised how dark this filter is. Doing a series of shot starting with a filter factor of 16 (4 stops) is a good idea