[Leica] leica swing out polarizer

["delia" <louzan@worldnet.att.net>]

In the last few months there has been a lot of talk about Leica swing out
polarizing filters.  They are great, though expensive and inconvenient if
you need to use them on several M lenses at the same time.  There was an
article in the now defunct Camera and Darkroom - June 93 issue, titled "Two
for One Deal, Viewfinder and Polarizer in One" by Frank Herzog (p 59). 
 
Imagine you need to use a polarizer on a 50mm f2 Summicron-M.  Buy a
39-52mm step-up ring (Tiffen, B+W, etc).  Screw it on the lens and mark the
area blocked by the step-up ring, while looking through the viewfinder. 
Take it off and drill a hole, then use a file to enlarge it.  It should
resemble one of the vented hoods invented by Bob Schwalberg.  Screw on a
52mm polarizing filter, and you're all set to go.  

If you want to use this adaptor with other lenses that have a 39mm filter
size, you may need to make additional holes.  The great thing about this
system is that it is inexpensive (about $12), and it allows you to use any
brand of linear, circular, or warming polarizers.  (Most polarizers tend to
shift toward green, so compare them by placing the samples side by side on
a light table and choose the most neutral.)

Regards to all,
Robert