Wanting to use a polarising (polarizing for some) filter on a rangefinder camera may seem a strange idea. Let's list the main objections to its sanity :

• There is a type of camera called the single lens reflex which makes the use of polarising filters easy with almost any kind of lens.
• The polarising filter is overused and leads to a lot of pictures with excessive color saturation.
• Finally, the polariser (polarizer if you are really hooked on Zs) is one of the thickest filters one can put in front of his lens, has a complex structure and is generally not multicoated, making it one of the most efficient ways to reduce the optical quality of the whole optical system.

However, I just like taking pictures with a rangefinder camera and the polariser does have some uses (reducing reflexions, color saturation when needed, ...). With all this in mind, I should like to be able to :

• Mount the same standard size polarising filter on all my M lenses, present or future,
• Be able to easily judge the effect in the viewfinder in real time while shooting.
• Additional constraints are that :
• The viewfinder should be obstructed as little as possible by the filter holder
• Yet one should be able to judge easily the effect
• I should prefer a system that does not require special attention from the photographer while composing and shooting
• It would be nice if it worked :
• With any filter
• With any M mountable lens even if not produced by Leica/Leitz
• With any rangefinder body, made by Leica/Leitz or any other (Cosina/Voigtländer, Fuji, Hasselblad, Konica, etc.)
• With accessory finders
• Cost is of course a consideration, even though one cannot expect a system made in very small quantities to be dirt cheap.

Messages posted on different newsgroups or forums on the internet seem to indicate that I am not alone in this quest.

There are some available products or solutions that more or less meet these requirements (see section 1 below for a description). I have had a look at them, tried the ones I could lay my hands on and tried to understand the others. I found most wanting (this is an opinion you may not share...).

Hence the idea of trying to design a better filter holder or at least one that would fit my requirements. These pages are here to share ideas as the design process progresses.

Rules of the game

I intend to have one such device made for my personal use but have no intention of making this item commercially available. If and when the design process ends - hopefully with a viable drawing - it will be made available to all for any commercial or non-commercial purpose. If you make a commercial use of the following ideas or drawings, you should share any improvement with everybody by making amended drawings or improvement descriptions available to all on this site with the same "free for all" right of use.

Suggestions on how to improve the design or these rules are most welcome.

Contact

My mail address is : barnoud@1839.org

Disclaimer

This is only an ongoing reflexion posted here as a basis for discussion. There is no warranty whatsoever that these ideas or their implementation will fit your needs or expectations.