circular vs standard polarizing filter

Started Dec 11, 2003 | Discussions thread
toughluck Senior Member • Posts: 2,951
Re: circular vs standard polarizing filter

Unless you plan to buy a (d)SLR camera with a beam splitter (semi-transparent mirror), don't bother buying the circular polariser.

Linear polarisers give much more possibility of creative work. Circular polarisers image change varies very little between various degrees.

Why a linear polariser won't 'hurt' your exposure, AF, nor final picture? Because a sensor actually records what it sees through the lens without any beam splitter, or anything similar. AF, light metering, et al, are done with the actual recorded image off the sensor instead of specialised sensors. The talk that 'circular polarisers work with digital cameras, and linear work with film ones' is absolute rubbish. A linear polariser won't work with a film camera that:

  • has AF and AE;

  • has a lens attached that turns its front element for focusing;

  • does not have TTL viewfinder.

The only thing that has been overcome so far is using circular polarisers with rangefinders, by adding a simple device that swings the polariser up and down to see its effect in the viewfinder. Even though it is much better than actual RF unpredictability, it's still not great.

That's wy for all those cameras, circular polarisers have been recommended over and over.

Actually, linear polarisers suffered when automatic SLRs became dominant enough to render lin-pols next to obsolete, or at least uneconomical to make in large quantities, and it was until digital era that linears had their renaissance, thanks to their lower price, higher creative value, (usually) better image quality, and the unnecessity of cir-pols. There is a multitude of sellers that push out "circular polarisers designed specifically for digital cameras" - there's no such thing. Light polarised parallel (through a linear polariser) is better received and perceived by the sensor than circularly polarised (which may hit sensor at high angles of incidence).
I do hope you understand what I've written here.
OzRay wrote

Can anyone recommend which polarizing filter is best for the A1 -
circular or standard and why? Thanks

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