IR IR IR

[Digital Matt]

Another question...how many stops do i "lose" using an R72 filter?

It's tough to say, because you are dealing with two filters. The one you put on the lens, and the one that is over your sensor, which partially blocks the infrared spectrum.

In total, the light loss between both filters is easily 10-12 stops.

 

[quad b]

atleast 10-12 is a good starting point for my exposures. i'll give it a go. thanks everyone