Quote Originally Posted by Brian C. Miller View Post
OK, it looks like you bought a 092. That's the correct filter, and it will work fine with all of the current IR films.

Filters cut off at a point, and let in light beyond that.
Films are sensitive up to a point.

So a film is sensitive up to 820nm. A filter at 900nm would be too much (80nm over), but a filter at 720nm would be fine, since it would let in light at 720nm and above.

The B+W 092 is what I use with Konica, Ilford, Efke, and Rollei.
The B+W 091 is what I used with Kodak, since I could still see through a SLR lens.
Thanks, and yes I got the right one few!!

The way some of the films read it seems they "start" at Xnm and give no indication of the cut off where they STOP, so it's a little confusing/deceiving, it also may be the distributors description being off. Either way glad I have APUG to clear it up