Originally posted by lkjr Docwrm- Do you screw in the CPL and then mount the Pentax hood?
The hood I have is the plastic Pentax PH-RBG model. The CPL I just bought is BW slim 58 mm. Once I screw on the CPL it looks like I can't screw on the hood anymore. That is kinda of a bummer. Is this combination incompatible? If so I wish I had known so in advance...
As I had mentioned in my original post, the only way I can mount both is to screw on the hood, then carefully plop the CPL in, take the door off the hood and then screw the CPL in. The problem is getting the CPL back out. It is easy to screw in through the window but if you screwed it in tight it is really hard to unscrew it via the door because you can't grab the ring from opposite sides.... and I can just see it getting stuck and not being able to comfortably back it out.
The Pentax PH-RBG hood is a bayonet hood that you put on then twist-lock into position (i.e. bayonet, not screw). A screw-in hood would have threads like a filter and would screw in on top of a filter, or perhaps would have a second set of threads to take a filter (not as common).
While I don't have a PH-RBG or B&W CPL, I have bayonet hoods and Hoya polarizers and haven't had any trouble slipping a bayonet hood over my polarizers while they're mounted on a lens. Sometimes polarizers have a bit of extra diameter to them because the part they design into the polarizer to be rotated has some extra grip to it, but it doesn't typically add much to the diameter. When your polarizer is mounted on the lens, does it protrude significantly, i.e. does it make the front of the lens much wider than normal?