Polarizing Filter Question

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jessh
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Post by jessh »

S8 Booster wrote: If found some info on the WEB that sort of confirms my impression that linear Polarizers do a better job than the CIR ones so go for a linear at least.
could you please point me towards this info?

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S8 Booster
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Post by S8 Booster »

http://www.kelvin.net/Hasselblad/hasselbladV1n1685.txt

You have to scroll down the page to find this:

Why's the circular polarizer the way to go? If you're using it on a
Hasselblad it doesn't make any difference what type of polarizer you get.
-- Unless the 205 uses some semi-transparent mirror for the spot meter.
Linear (top) polarizers are more effective than their circular counterparts so you get a more pronounced effect of the polarization. This effect is obviously adjustable by turning the filter ring.

You will need a circular polarizer in the following situations:
1) If you're using auto focus.
2) If the metering system in your camera requires it (typically only spot
meters require circ. pol., CW and partial meters are fine with the lin. pol.)


Some more about CIR vs POL;

http://www.pechorin.com/messages/95552.html

Scroll to find:
Re: Circular True-Pol Polarizing OR True-Pol Polarizer- beaser - 25th Sep 2002 8:04
You'll have to retype your reply, I don't fully understand it.
I've been through this particular escapade before and I get angry with the lemming philosphy. I get the "safe" answers every day on a multitude of topics. I'm a tech and it's my job to solve problems and to sweep away the BS. The safe answers usually cost people a lot of money. No picture on your TV? We'll just change all the parts , just to be sure.
I had actually called tiffin and asked a tech support type the question. The answer was use circular. I asked to speak to someone senior. I asked why I had gotten that answer when the following is posted on the Tiffen site under polarizers
http://www.tiffen.com/ultrapol.htm
Some camera-related optics,like a video tap, employ a
partially silvered mirror, or beamsplitter. This may require the use of a Circular UltraPol, which places a clear, quarter-wave retarder on the camera side of the filter,effectively de-polarizing the light being recorded, after the image enhancement is done. Circular UltraPol filters are suitable for virtually all situations; Linear
UltraPol filters excel in traditional applications.
Since canon or Sony don't use a video tap or a beamsplitter the boss man figured it was OK. I asked him why they recomended the circular and the answer was it was easier to just recomend it accross the board in case you wanted to use your polarizer on yoyr SLR too. I personally consider that a technical cop out.
Instead of arguing, buy one and try it, it's half the price. I use a linear on both my cams and I'm a bloody purist. I won't own crap.
Try it, you can't loose. If it doesn't work , not only will I kiss your butt but I'll give you an hour to draw a crowd. You can return it and pay the extra and still have your circular.
Note: most of the people on the help desks shouldn't be there. They're reading safe answers out of a book.
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R
..tnx for reminding me Michael Lehnert.... or Santo or.... cinematography.com super8 - the forum of Rednex, Wannabees and Pretenders...
Guest

Post by Guest »

Hi, NIck.
Sorry for the delay.
According to my check, I confirm you what someone else has already said: you should be able to use both a linear and a circular polarizer on the Canon 1014 XLS. But with the former you should be prepared to accept some degree of loss in brightness inside the viewfinder, which will make operations less comfortable (about 35%). This should not affect exposure though. With the latter polarizer, instead, you will not experience such a problem, just some sort of yellowish hue when rotating the filter to a certain angle, but no decrease in brightness in the vew finder.

Hope this helps.

Ciao

Maurizio
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