----- Original Message -----
From: Brian P. Huber <bphuber@xxxxxxxxxx>
To: 'olympus@xxxxxxxxxxxxxxx' <olympus@xxxxxxxxxxxxxxx>
Sent: Sunday, April 18, 1999 12:42 PM
Subject: RE: [OM] ** FILTERS **
> John,
> I think you are addressing two different things here: polarizers and UV
> filters.
> I haven't seen comments about B+W, but some companies do make two versions
> of filters. Some filters (more expensive) are made thinner so as not to
> interfere with wide angle lenses. That's one nice thing about OM filters,
> notice how thin they are!
> Some Tiffen filters for example are quite thick (the metal mount), some
> Hoya's are too, but some special Hoya's are quite thin. My guess is that
> B+W has used some of the same manufacturing techniques. Maybe they're
just
> following the lead of Olympus.
> Use of a UV or Skylight is rather a personal matter, there are camps both
> ways.
> Brian Huber
I was not referring to UV or skylight filters. One of the two polarizing
filters was half the thickness of the other. Both of them had two rotating
filter elements. Either the elements themselves in the thinner of the two
filters were only half the thickness of the elements of the other, or the
distance between the two elements in the thinner filter was half distance
between the elements in the other filter. The front to back thickness of the
mounting ring in both filters was almost identical. Whichever is the case,
the distance between the outer surfaces of the rotating elements of one
polarizer was about half the distance between the rotating elements in the
other. I would have to conclude that all others being equal the thinner of
the two polarizers would be preferable to the other.
John Hudson
ps: I recall visiting Pilkington Glass Co in St Helens, Lancashire in the
late 1960s. Among the products on display was a cylinder of glass mounted on
a tripod. The cyclinder was about 1.5" in diameter and 48" long and was
pointed towards an illuminated chart of letters on the wall about 10' away.
Looking through the cylinder the letters were as clear and crystal sharp as
looking through my prescription glasses alone!
>
> -----Original Message-----
> From: jahudson [SMTP:jahudson@xxxxxxxxx]
> Sent: Sunday, April 18, 1999 12:15 PM
> To: LIST - Olympus
> Subject: Re: [OM] ** FILTERS *
>
> I wonder if someone could comment on something I heard yesterday in one of
> our mainline camera stores about UV filters. The store person mentioned
> that
> B+W makes two types of polarizing filters; one with the distance between
> the
> two rotating filter pieces the same as that of other manufacturers, and
> another where the distance between the two rotating filter pieces is much
> smaller. The store person opined that the latter type of polarizing filter
> could be used with wide and very angle lenses without any negative
> consequences. My experience with UV filters is limited having only
> acquired
> an SLR earlier this year. As a long time rangefinder camera user I never
> used a UV filter so have no experience in that field.
>
> John Hudson
>
>
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