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-   -   F3 require circular polarizer? (https://www.dvinfo.net/forum/sony-xdcam-pmw-f3-cinealta/493855-f3-require-circular-polarizer.html)

Leonard Levy March 31st, 2011 02:33 AM

F3 require circular polarizer?
 
Do you need a circular polarizer on this Cam?

Dennis Dillon March 31st, 2011 08:06 AM

Re: F3 require circular polarizer?
 
No there is ND built in. Slide position 1=1/8
Slide position 2=1/64

Iam not a fan of using Circ Pol to reduce light. I find they tend to color shift skin tones. But I do love a polarizer for landscape work.

Leonard Levy March 31st, 2011 08:47 AM

Re: F3 require circular polarizer?
 
I'm not talking about equating a polarizer with ND, I understand the difference. Wondering if this camera requires a circular rather than a standard polarizer like some other cameras - the EX-1 for example.

Dennis Dillon March 31st, 2011 09:44 AM

Re: F3 require circular polarizer?
 
Leonard,
Sorry, I had that circular ND thing in my head. Not sure by what you mean by "requires".? I believe any camera would benefit from a circular polarizer. It gives more choices on your angle of subject. I have always used a matt box with a rotating frame.

Leonard Levy March 31st, 2011 01:19 PM

Re: F3 require circular polarizer?
 
There are regular non-circular polarizers and i can get a good 4x4 used locally cheap - And there are "circular polarizers" that are needed for some kinds of cameras depending on the chip type and the method of doing auto-exposure. I would need to buy new. My question could also have been phrased - can I use a standard pola.


Sorry, Perhaps that would have been clearer.

Nate Weaver March 31st, 2011 02:38 PM

Re: F3 require circular polarizer?
 
Quote:

Originally Posted by Leonard Levy (Post 1633757)
There are regular non-circular polarizers and i can get a good 4x4 used locally cheap - And there are "circular polarizers" that are needed for some kinds of cameras depending on the chip type and the method of doing auto-exposure. I would need to buy new. My question could also have been phrased - can I use a standard pola.


Sorry, Perhaps that would have been clearer.

Circular polas are for cameras that meter or have AF sensors behind the mirror (SLRs)

No such thing on this cam. Standard cine linear polas will work fine. I'm using my 138.

Leonard Levy March 31st, 2011 03:05 PM

Re: F3 require circular polarizer?
 
"Circular polas are for cameras that meter or have AF sensors behind the mirror (SLRs)"

Not limited to those situations. EX-1's need a circular polarizer .
However if you're using one that sounds good enough for me. Thanks Nate.

Chris Medico April 1st, 2011 05:49 AM

Re: F3 require circular polarizer?
 
Once I have mine and work out the lens adapter I'll be able to check it out. I've got both types.

I am interested to see if there is any color shift with a LIN like there is on the EX1.

Brian Lai April 1st, 2011 06:05 AM

Re: F3 require circular polarizer?
 
Even though we don't meter through the F3 camera, I do check the brightness level indicator and histogram against my exposure, and if light reaching these two indicators is compromised by a linear polarizer in the same way it compromise an auto meter system, then in theory the readings of the level indicators and historgram are compromised too. Please correct me if I'm wrong, but I've been using a circular polarizer even though it's less effective and more expensive for the reasons above.

Also get the thinnest pola you can find. B&W makes a good one.

Nate Weaver April 1st, 2011 11:16 AM

Re: F3 require circular polarizer?
 
Quote:

Originally Posted by Brian Lai (Post 1634036)
and if light reaching these two indicators is compromised by a linear polarizer in the same way it compromise an auto meter system

It's not compromised in the same way. An SLR has light meters and AF sensors in half-silvered areas behind the mirror. Linear polas mess how light reaches those sensors, in conjunction with the mirror. Completely different system.

In the F3, the exposure meters are based off the entire video image created from the sensor.

Leonard Levy April 1st, 2011 12:55 PM

Re: F3 require circular polarizer?
 
I asked this because unexpected issues can affect polarization
On the Ex-1 you get unexpected color shifts from linear polas that probably have to do with the beam splitter. But obviously not all 3 chip cameras needed a circular polarizer.

http://www.dvinfo.net/forum/sony-xdc...olarizers.html

So I'm looking for hands on observations, not theoretical stuff that may or may not be relevant. Nate said he is using a linear. That was useful information.

Nate - Do you mean a 138mm pola - what brand ?

Chris Medico April 1st, 2011 01:00 PM

Re: F3 require circular polarizer?
 
I am guessing it won't be a problem on the F3 since there is no prizm setup. I will be testing it as soon as I get a lens adapter.

The F3 camera body arrived today.

Chuck Fishbein April 1st, 2011 01:25 PM

Re: F3 require circular polarizer?
 
Lenny,
I've used my F3 with both Tiffen and Formatt linear and circular polarizers and both without issue.
I have all of my filters in both 4x4 and series 9

Charles Papert April 2nd, 2011 04:08 AM

Re: F3 require circular polarizer?
 
It's been a few years since I've seen this one come up but it never ceases to confuse people. Hopefully everyone reading this understands at this point that circular polas have nothing to do with either the shape or the rotation of the actual filter.

I myself use a Schneider True-Pol 138. It's linear. I've never in my entire career needed to use a circular pola. Not to say there aren't a few cameras out there that require it; I just haven't used those, I guess.

Chuck Fishbein April 2nd, 2011 11:08 AM

Re: F3 require circular polarizer?
 
I believe that is well understood her Charles, yet, in recent years, several video cameras and certainly many DSLR cameras have required circular polarizers to function properly. These cameras used some form of polarization in their metering system and I believe in some cases, auto focus systems. In some cameras it was obvious, like the viewfinder going dark or looking a bit posterized, other times, it shifted the color.
I think either my Z1 or PD-150 suffered from this.


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