Question about Drop in filters

[bob williams]

Since I rec

[neuroanatomist]

Hi Bob,


As far as I know, there aren't any 3rd party alternatives to Canon's drop-in PL C-52. That CPL includes a geared mechanism that allows you to rotate the CPL via a knurled knob on the outside of the holder. So if you want that feature, I think you're stuck waiting until Canon produces another batch of them, or until you can find one on eBay or FredMiranda.


One possible alternative would be to use a standard 52mm CPL with Canon'sDrop-In Filter Holder for 52mm Screw-In Filters - except that the holder is also out of stock everywhere (likely, Canon produces them in parallel with the drop-in CPL).


I don't think there's a resin CPL large enough to go in front of the front element - the Cokin Z-Pro series is 4x6", and I think the 500L's front element diamater is larger than 4". I know there are larger CPL's outside of the photography realm (they're used in 3D/holography applications, too) - I ran across an 8" square glass CPL that is large enough for your lens, but at $1500 it's probably not a viable option...


The drop-in holder that came with your 500L is for gelatin filters only. So, that brings me to the last alternative - a sheet of circular polarizing film inserted in the gel holder. This would probably be the least convenient option, because to change the orientation of the polarizer, you'd have to remove the cartridge, open the gel holder, rotate the gel (without getting fingerprints on it), and then close and re-insert it. Circular polarizing film is not easy to find, but there's at least one online source(the material is 0.3mm thick, similar to a Lee gelatin filter, so it would fit in the holder).


Hope that helps...


--John

[bob williams]

John, Thanks for the detailed response. You have educated me "again". I didn