Voigtlander Filter Adapter for 12mm f/5.6 Heliar Lens (Allows use of 77mm Filters)

Comments about Voigtlander Filter Adapter for 12mm Lens (77mm Filter):

With the 12MM f5.6 being the widest wide-angle lens aver made for 35MM film (or "full frame, to you DSLR buffs) it would seem that any obstruction in the form of filter rings would cause noticeable vignetting. This adapter allows for the use of the 77MM size filters, and that is apparently a large enough diameter as to eliminate concerns of light fall-off in the corners.

Of course, 77MM filters are pricey as well as bulky, so if you were to take a few of them (say, a few different NDs to allow for slower shutter speeds or some orange or red if you shoot B/W) you need to allow for that added bulk to carry. I also used a circular polarizing filter - of course the results were not overly obvious since with the 121 degree angle of view it's impossible for the entire sky to get the effect. What I did do to ensure maximum polarizing effect was remove the entire filter/adapter (much quicker than unscrewing the filter itself), turn the assembly to get the desired effect, then return it to the lens in that orientation.
There is a "slot" along about 1/3 of the adapter flange, no doubt to allow for viewing through it (otherwise the flange would block the viewfinder altogether). However, I use a Bessa L which doesn't even have a built-in rangefinder/viewfinder, so for my purposes this was moot.
FOr those wide-anglers out there who want to use some filtration on the amazing 12MM lens, this is highly recommended.