Filter size of my Voigtlander 35/2.5 MC Color-Skopar lens?

[brian steinberger]

I have this lens on my Voigtlander Bessa R that I bought a few months ago, and

I'd like to purchase a circular polarizer for it. But the filter size is not

marked on the lens. The lens is the 39mm Leica screw-in type. I measured the

front of the barrel and come up with what looks like excatly 40mm. But they

don't make 40mm filters, just 39mm and 40.5mm. I thought that maybe since the

rear threads are 39mm that they made it easy and made the front filter threads

39mm. Anyone have this lens that can help me out? Thanks

[vivek iyer]

39mm.

 

http://cameraquest.com/voigtlen.htm

[leicaglow]

Okay, here's a really dumb question: I've never used a circular polarizer on a rangefinder camera. How the heck do you set it since you can't see through it in the finder?

[vivek iyer]

Same principle as discussed here:

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00H266&tag=

[jose_angel]

Screw the filter on the lens. Draw an alignment mark on the filter barrel at the same point of the distance reference mark of the lens. Unscrew the filter and look throught it turning the front ring until the polarized effect is as desired. The filter must be with the drawn mark uptairs, like when attached to the lens. Then screw the filter as it is to the lens and shot.

[graham_line]

Why do you need a circular polarizer for a Bessa R? Standard linear polarizer will work perfectly and cost less.

 

B and H lists step-up rings that let you match the thread on the lens to the thread on your accessory -- I have a 39>40.5 step-up for my VC 28/3.5.

[david_l3]

You probably don't need a circular polarizer with a rangefinder. A linear polarizer is a bit less expensive and will work the same. Circular polarizers are needed in SLRs that have semi-silvered mirrors and other types of beam splitters for their TTL light meter systems. Leica RF cameras will work fine with linear polarizers. I'm not familiar with the design details of Bessa camera meters to know if a linear polarizer will work.

[dan flanders]

Someone once convinced me that I needed a circular polarizer

on my M6. I had a Leica swing-out polarizer that had separated

so removed the glass and replaced it with a circular polarizer

of appropriate size. It worked quite well but I eventually was

apprised of the fact that I didn't need the circular version

anyway. One of these days when I trade for a plain polarizer I

will change it back but for the time being the circular is

adequate to my needs.

 

Chances are that the outside diameter of your lens flange is 42mm

if the threaded recess is E39. Some lenses with 40mm recesses are

also 42mm O.D.

[jose_angel]

"... Standard linear polarizer will work perfectly and cost less". Absolutely. In my experience, linear polarizers works better than circular ones; as David says, unless you are using an AF or mirrored system there is no need of a circular polarizer.

 

I understand that Leica metering system is based on the reading of the ammount of light reflected by the white dot (21mm diameter?) painted over the shutter curtain. I don`t see the need of a circular polarizer filter for such big area of measurement. Don`t know about Bessa systems.

[brian steinberger]

So a linear polarizer gives the effect of a circular one on full polarization? You cannot acheieve in between effects?

[lee_shively]

Don't complicate things. It takes a 39mm polarizer--linear or circular doesn't matter. To use it on a rangefinder, just look through the filter as you rotate it, note the position of the ring at the level of polarization you want to achieve, screw the filter into the lens and reposition the ring to that same postion you noted.

[graham_line]

"So a linear polarizer gives the effect of a circular one on full polarization? You cannot acheieve in between effects?"

 

Screw-in polarizers all come in rotating mounts. You rotate the polarizer to change the degree of polarization.

 

There's anecdotal evidence that linear polarizers can achieve a more dramatic effect than the circular versions that are required for some applications. I'm not aware of any direct comparisons. But as Lee points out, the question is pretty much immaterial for current rangefinders. Linear pols are generally less expensive.