Linear vs. Circular polarising

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I've read the earlier discussion on this matter, and the explanation of the effect on metering makes sense. It seems (please correct me if I'm wrong) that, depending on the type of metering in the camera, the linear polariser may or may not be ok.

So far so good. Now my question. I have an Autoreflex T, TCX, and FS-1. Are any of these units ok with the linear polariser? I guess the question should be - are any of them not ok - in that case I should go with the circular polariser.

Mark Webster

-- Anonymous, August 01, 2000

Answers

polarizers

hi mark,

linear polarizers will work fine with your konicas. If you haven't bought a polarizer yet though, get a circular one so you can use it with cameras that use a beam splitting mirror or prism to meter light. Hope this helps.

cheers, glenn

-- Anonymous, August 01, 2000


Circular v. linear polarizers

The principle behind polarizers, as I understand them, is that light reflected from flat surfaces (i.e., glare from the surface of a lake) is polarized orthogonally to the surfaces (or is it parallel?). Anyway, a linear polarizer oriented 90 degrees to the reflected polarization will, in theory, cut out all the reflected light. A circular polarizer will cut out all light that is circularly polarized with the opposite sense. Linearly polarized light, polarized in any direction, should pass through a circular polarizer, but with some fixed loss.

So, I don't think circular and linear polarizers do the same job. However, I should admit, that, although I own a linear polarizer, I have never used a polarizer on a camera. So, this explanation could be all wet. Can someone with experience confirm or deny this?

-- Anonymous, August 01, 2000


Polarisers - also 80-200 f3.5 zoom

Thanks william and Glenn for your help

As a result I went out yesterday looking for a circular polariser, but when offerred a used linear for $10.00 I thought what the hell!!

The same shop had a Hexanon zoom 80-200 f3.5 at $95.00 (Aus) in great condition that I couldn't resist. Big and heavy, and with 'EE' rather than 'AE' on the aperture ring, is clearly pretty old. (see - I've done my research thru the old postings !!!) Does anyone have any experience or comments on this lens? The Wulff site doesn't say much - '...generally decent performance for the time...' , which isn't exactly glowing. I've been using a 200mm Soligor for some time, could I expect this zoom to produce sharper images?

TIA

Mark Webster

-- Anonymous, August 02, 2000


Circular vs. linear polarizers

I have always wondered about circular polarizers in photography. As you suggest, a true circular polarizer won't pass circularly polarized light (for a correct definition, light in which the electric vector rotates). Also as you say, it doesn't do the same job as a linear polarizer, which would seem to be better suited to filter out reflected light, darken the sky (skylight is naturally polarized) etc.

I recently read an explanation which said that a circular polarizer as used in photography is a linear polarizer followed by a depolarizer. I don't know for a fact that this is true, but it makes a lot of sense. It does mean that it's not a true circular polarizer like you read about in optics textbooks.

Such a filter would let you cut out reflections by rotating the filter and then depolarize the light out, so it wouldn't affect the autofocus gizmo.

A warning...I use Konica equipment, obviously, and no autofocus. So I do use a linear polarizer occasionally, but I've never used a circular polarizer.

Best, Steve

-- Anonymous, August 07, 2000


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