Linear or circular polarizer? Need help

[Shawn Nelson]

I need to get me a polarizer that will be used on my RPPs, Red 300mm & the occasional odd lens (such as my old Angeneiux 25-250mm T3.9).

My matte box is usually the RedRock for which I obtained a 5.65x5.65 filter tray, and sometimes I use a smaller light-weight 2-stage Chrosziel 4x5.65.

Two part question:
1. Do I get linear or circular? I've long though of circular as superior, but recently I heard that circular is only needed if being used on a CCD system. Really? Don't you still need to be able to rotate? I'm confused. I also read David Mullen talking about Circ Pols sometimes causing artifacts in the sky on a pan. Whoa! Can Linears do this too?

2. Size: 4x5.65 or 5.65x5.65? I supposed this is related to part 1. If I get linear then I might as well only get 4x5.65 since I won't be rotating it.

It's odd to be coming into this problem now. I had previously solved this by having a 72mm screw-on circ pol that I used on my Red 18-50mm, nice and light, but now have different lenses.

[George A.]

Hi Shawn!

Look more into the differences between circular and linear polarizers. You can rotate a linear polarizer, no problems. Circular polarizer means something else.

Check this for a start:

http://reviews.ebay.com/Circular-vs-...00000002144386

[Liam Hall]

You only need a linear polar but you still need to rotate. Circular polar filters are for autofocus cameras.

[Shawn Nelson]

Okay, so my Red doesnt autofocus, but Epic/Scarlet might and i'll probably get both of those. A 5.65x5.65 circ pol is the same price as the linear.

What's the disadvantages of going circ?

[Matthew Rogers]

You only need a linear polar but you still need to rotate. Circular polar filters are for autofocus cameras.

Close, but not quite. I believe circular polas are for any camera that has a prism in it. So a film camera that has a video tap needs one and so does any 3CCD camera (which are most pro broadcast cameras.)

I may be wrong about that, but I know you are supposed to use a circular pola if you have a video tap on a film camera.

Matthew

[Stacey Spears]

Shawn,

I have a pola frame if you are interested. I originally paid $1100, but am willing to sale it for $500. It uses a Schneider linear pola inside. It fits in the RedRock mattebox. It is what I used when I had the mattebox. I now have an MMB1 and had to get a smaller filter.

Here is a picture of the filter. http://www.filtergallery.com/Non-Chromatic_Filters.html

[Jamesl169]

"A Circular Polarizer has the same effect as a Polarizer and is used on cameras with beam splitting metering systems commonly found on auto focus SLR's (for most 35mm auto-focus cameras see your camera manual). "

Direct from Tiffen filters.

"Beam splitters send light in two directions: to an eye-piece and to a video tap. Light in a camera’s viewing system can become polarized, and when a standard (linear) polarizing filter is attached to the lens, the light becomes cross polarized. This hinders visibility and may create total black-out of the viewing image and/or the video tap."

Direct from Schneider Optics B&W filters.


Hope this answers your question.

Regards,
James

[Rich Schaefer]

Be safe and get the circular, it will work with all cameras.

Liner will work on most cameras, but it there is a beam splitter like on my Moviecam Compact or many Arris the video or eyepeice will go black as you rotate the filter. Its a pola vs/ beamsplitter coating issue....

Prost,
Rich

[Sanjin Jukic]

"Circular Vs. Linear Polarizers

There are two types of polarizing filters available — linear or circular.

Linear polarizers are more effective and less expensive than circular ones.

But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens.

If that light is linearly polarized it renders either the metering or the autofocus ineffective.

This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera."

More>>>

To conclude is to say if you use a linear polarizer (for manual focus camera)...

[Jeff Kilgroe]

Linear is fine for RED now... But I would get the circular. It may future-proof you if upcoming Epic S35 or future cameras offer autofocus ability with the RED mount electronic lenses... Circular isn't really any more expensive these days. 4x5.65" size covers the RPPs fine, but you'll want a 5.65x5.65 for pola or grads you rotate.

I like the Formatt 5.65x5.65 one and it's around $260 from AbelCine or FilmTools. The Tiffen and Schneider ones are good too.