The Hoya R72
High quality, but little use.
I have included this filter (among others) so that people do not waste their money. In particular, this filter could well set you back several hundred. Unfortunately it would be wasted money.
The filter begins transmission at around 720nm which is far too short a wavelength. In fact, you can see through this filter with the naked eye. Any filter you are considering should appear totally black and you should not be able to see through it (unless you look at the sun - NOT recommended!).
Filming with this filter will give you no results whatsoever. Please note that there is some confusion about the model number. Some people have in the past referred to this filter as the 'RM72' (possibly because of the RM90) but it is actually 'R72'.