Re: Which Polarizer?


"AaronW" <bj286@xxxxxxx> wrote in message
news:1154220216.398429.202810@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Roger wrote:
I have a Canon XT with a Sigma DC 18-200mm 1:3.5-6.3 lens, so obviously
I'm not a Pro!
However I'm trying to decide on a circular polarizer filter

A linear polarizer is better.

for enhancing sky colors and minimizing reflections.

What I like most about polarizer is to enhance the color of grass,
flowers, and trees, ...

I hear that circular filters can knock 2 f-stops off a lens. Since I
already have a slow lens,

This can be a problem.

would a more expensive filter take less of a
toll than a cheap one?

No.

What are the considerations? Any recommendations?

Just get a cheap polarizer, to see whether you like the effect. If you
want a better one later, maybe with a better lens, get a multicoated
linear polarizer.

http://digitcamera.tripod.com/#slr

Anyone else posted to say that a linear polariser is a bad idea with an
autofocus / TTL metering body?

AFAIK, such bodies use beam splitters and so have to be used with circular
polarisers.
To cope with the loss of light, load the camera with a faster film than
usual (or set a higher ISO than usual if you're using a difital body).

Note also that the effect of the filter will depend on the relative position
of sun, camera and subject. I found, taking the "classic" photo of boats in
a small harbour on a sunny day, that in one position the filter had very
little effect whereas in another position the effect was mich more
noticeable.


Regards, Ian.


.

Relevant Pages

  • Re: Playing with polarisers- color effects
    ... quarter-wave plate is only a quarter-wave plate at one wavelength, ... as you depart from that wavelength, ... In the visual wavelengths, the polarizer is extremely good, effectively 100%, so crossing them gets rid of all that light. ... But at the shortest wavelengths the filter is less than 100% effective, so that crossing two of them will still transmit a bit of unpolarized purple light. ...
    (rec.photo.digital)
  • Re: polariser filter
    ... Filter is defective. ... It's always been a pot-shot buying polarizers by brand name. ... and with luck you'll get a polarizer worth 2x's what that Hoya cost ... purchased filter materials. ...
    (rec.photo.digital)
  • Re: Rotating polarizing filters
    ... in a position the filter is transparent and after a rotation, ... The difference is due to the 'circular polarizer' not actually passing circularly polarized light. ... Left and right circular turn into two orthogonal linear polarizations, and one of these is selected by a bit of linear polarizer film. ... However, since this makes very little difference to images, nobody ever does this, so circular polarizers that you buy actually turn circular to linear and pass the linear. ...
    (sci.optics)
  • Re: "Sports" Polarizer
    ... You can get two basic types: one just is a simple linear polarizer, and the other first does the linear polarization for the effect that you want and then converts that linearally-polarized light into circularly-polarized light. ... The circular filter is used for cameras with internatl reflections that could potentially interact with linerally polarized light and perhaps throw off light metering. ...
    (rec.photo.digital)
  • Re: "Sports" Polarizer
    ... It was is NOT to be confused with the current circular ... filter was circular. ... Since most scenes are illuminated from above on average, the linear polarization present in reflected light will be tend be horizontal in direction. ... A cilcular polarizer consists of a linear polarizer, which does the required filtering, followed by a quarter-wave retarder, which converts the linearly-polarized light to circularly-polarized light, which behaves better inside a camera with internal reflections. ...
    (rec.photo.digital)