Hi, I recently bought some Singh-Ray ND grads in P size, and got both the wide-angle and standard Cokin P holders, for use with my 5D mk II and 17-40 lens. I was intending to use a screw-in polarizer (Marumi Super DHG) on the lens and then screw the filter holder w/ grads onto that, but turning the polarizer while keeping the holder stationary proved to be a real pain in the arse, perhaps due to the CPL being so slim (4-5mm).
I'm now contemplating on purchasing a Singh-Ray warming polarizer or Colorcombo in P sprocket size for use in combination with the grads/holders, but have a couple of questions I've not had much luck finding answers to elsewhere.
Firstly, I've already confirmed the wide holder doesn't vignette at 17mm, but if I were to use a sprocket polarizer with this holder, would the corners of the filter (not the holder) be visible at this focal length? I realize I wouldn't be able to mount a grad onto the wide holder as well in this case, but that's not a problem, I'd just handhold it.
Secondly, with the regular P holder, is it possible to mount a sprocket polarizer and two ND grads, or just one? Not sure about the thickness of the sprocket polarizers.
Cheers
