do Polarizers make a difference? - Page 2 at DVinfo.net

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Old December 2nd, 2002, 05:27 PM   #16
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Polarize it !

To add some non-technical stuff here...........

I've mentioned a few times before that in our films & footage, we use nothing but Hoya Circular Polarized filters on the XL1s.

Big blue skies, and what a way to film fish in their natural habitat. It suppresses a huge portion of the reflection of light from the surface of the water.

On accident (wasn’t trying for the effect) I filmed an almost surreal shot where the sun was off to the left of the lens view about 30 degrees, spotty but thick clouds, water moving down river, my partner fly fishing in the center of the frame………

It was one of those things you will never recreate until you figure out how to control Mother Nature.
After panning another 30 or 40 degrees to the right on the tripod, the effect was gone……..

In my neck of the woods……circular polarized filters on the XL1s are a “must have” in your bag of tricks.
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Old December 2nd, 2002, 08:14 PM   #17
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Let's put this in a context that everyone understands, money.
Buy a $20 linear and try it, if it doesn't work exchange it for a $40 circular. N'uff said?

(prices bases on a 58mm tiffen from B&H)
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Old December 2nd, 2002, 09:09 PM   #18
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Sure, lets put it in context. Someone spends $3500 USD for an XL1. He goes on a once in a lifetime trip or shots a project for a client that can't be reshot. Then finds out if he had spent $20 more he could have gotten better shots. That's 1/2 of 1% of the cost of the camera. The $20 all of a sudden seems insignificant in comparison with the cost of the camera, a major trip or impressing a major client. Risk any or all that for a measly $20. Not after what I've already invested.

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Old December 2nd, 2002, 09:43 PM   #19
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I have a B+W Circ Pol, It uses the newer F-Pro format B+W has adopted, slimmer than the older style. It has an adjustment ring Adrian spoke of, but I haven't seen any noticeable difference when using the ring...
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Old December 2nd, 2002, 09:57 PM   #20
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filters

<<<-- Originally posted by SyneticDV : It has an adjustment ring Adrian spoke of, but I haven't seen any noticeable difference when using the ring... -->>>

Same here....no visible difference (to me anyway)
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Old December 2nd, 2002, 10:14 PM   #21
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Circular and linear polarizers are manufactured to rotate in a circular manner. This enables you to rotate the filter in relationship to the angle of reflectance. When looking at the blue sky through a polarizer (either circular or linear) you will see the sky darken and lighten as you rotate the filter. The rotating mounting ring (not the threads) is how you adjust the degree of polarization. References to circular or linear relate to the manner in which the light is polarized, not the rotating mount that both types share.

Complete details on polarizing filters can be found by using the search function as this topic has been discussed in length before.

Jeff
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Old December 2nd, 2002, 10:17 PM   #22
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I have a Heliopan linear polarizer. When I hold it up to the sky and rotate the front of it, there is a very visible difference. The difference is easily noticable through the viewfinder as well.
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Old December 9th, 2002, 09:05 PM   #23
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Regarding circular polarizers:

Be sure to have the right side of the filter facing the lens. The Lee circular polarizing filter is packaged with a slip of paper that's easily overlooked. It says, "Circular Polarisers will only work correctly in one direction. Please ensure that the filter is positioned in the holder so that the printed surface faces away from the lens."

If you keep the proper side away from the lens the difference is easily noticed. If the wrong side faces the lens the difference is almost non-existent. This mistake is easily made with square filters that are slipped into matte boxes.

Other than that, circular and linear polarizers do function the same way. They both have to be rotated or oriented properly to block out unwanted reflections and/or make the sky more dramatic.

Dean Sensui
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Old December 10th, 2002, 12:23 AM   #24
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Greg Vaughn, or anyone else who might know!

you stated:

((( ....I own the 3 piece Canon filter kit for each lens I own and don't shoot outside without the polarizer. I shoot a lot of aircraft and can get a nice medium blue sky if I want it. One thing I've found is that I have to do a white balance after each adjustment of the filter or I get a purple sky,)))


Lets say you were using your filters and were using a monitor with it, like a flat Nebtek monitor on the XL1s, would you be able to see the effect on the monitor? Or would you be shooting blind (considering you have a B&W viewfinder)

thanks
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Old December 10th, 2002, 01:14 AM   #25
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The effects of a polarizer, being primarily a luminance issue (the sky is not so much getting bluer as darker when the pola is applied), can be viewed with a black and white viewfinder. If you have zebras enabled, you can actually see the zebras diminish as you rotate the pola.
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Old December 10th, 2002, 02:08 AM   #26
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Charles,

But can the effects be seen on a monitor? Lets say you use a different filter, or maybe use several at once and get a weird hazzy effect, will it show up on the monitor?

thanks
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Old December 10th, 2002, 03:45 AM   #27
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Indeed Charles, the sky gets darker because part of the scattered (and polarized under certain viewing angles) blue light gets absorbed by the polar. The cloudless sky looks bleu because of the scattering of sunlight on different molecules in the atmosphere (air, dust,.. ). If this scattering would not exist, the sky would look perfectly black (like it is for the astronautes)
Of couse Gateway, the effect can be seen on a monitor.
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Old December 10th, 2002, 04:12 AM   #28
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For what it's worth, Panasonic Tech says either circular or linear polarizers will work with their DV cams.
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Old December 10th, 2002, 06:15 AM   #29
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Cheap filters can cause a color shift. It was discussed a little here http://www.dvinfo.net/conf/showthrea...D+color+Tiffen I think the word purple is a bit strong, but I have seen colors change with the use of poloraizers. I used a poloraizer on a very cold (-20F) day, very clear (little pollution) and it turned the sky very, very dark blue.

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Old February 17th, 2003, 11:02 AM   #30
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Just a thought on why some folks are not seeing a difference with polarizer use.

If the camera is in a fully Auto mode, it will adjust exposure and white balance as the filter is being rotated. In Auto mode it can be difficult to discern when the polarizer is affecting the scene.

Shooting in manual will best show the polarizer's effects.

Ron Johnson
Portland, OR
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