This Cokin Polarizing B 160 filter—and its clever case—showed up in a bargain bin for a $1. At that price how can anyone refuse?
The case is also labelled on the end. Those who use the Cokin filters often acquire quite a few filters. So Cokin used to make boxes that would take the cases in slots so you could read the ends to figure out how to find the one you were looking for. Notice you are also told what the exposure correction would be needed if the filter was used. The “COEF. X 3.5” was how much you needed to increase the exposure to compensate for the filter density. You need more exposure, but explaining it as “X 3.5” has it’s problems. If increasing the exposure 2X is one stop, then increasing 3.5X is slightly less than opening two stops.
Those with some through-the-lens exposure systems can get fouled up with linear polarizers. If the camera uses a half-silvered mirror to tap off the meter reading, then a linear filter almost completely closes off the light, resulting in completely fouled up readings. To fix that problem they developed circular polarizers. Neither linear or circular refers to the shape of the filter, but rather to the way the filter’s “slats” are orientated. A linear polarizing filter has fine slats like a venetian blind. The circular filter has the slats as a circular pattern like a really fine bull’s eye target.
Those with some through-the-lens exposure systems can get fouled up with linear polarizers. If the camera uses a half-silvered mirror to tap off the meter reading, then a linear filter almost completely closes off the light, resulting in completely fouled up readings. To fix that problem they developed circular polarizers. Neither linear or circular refers to the shape of the filter, but rather to the way the filter’s “slats” are orientated. A linear polarizing filter has fine slats like a venetian blind. The circular filter has the slats as a circular pattern like a really fine bull’s eye target.
The Cokin polarizers were available as “A” (linear) and “B” (circular) versions, in at least two major series. There was an amateur size and a much larger “Pro” size. This is an amateur size filter, meant to slide into the smaller Cokin filter holder. The toothed rim allows you to rotate the polarizer as you view the scene through your lens.
The filter rotates on that smooth rim just below the toothed edge. It is surprisingly smooth and frictionless. Although setting yourself up with Cokin filters requires buying the filter holder, an adapter for your lens, and finally a filter, it is fun once you get set up!
Finally we are going to explain how important a polarizer is. But first a personal insight. When I was very young, and my family realized how important photography was in my life, my mother took us to a public show in a huge auditorium (it was Eaton’s or Simpson’s and so large it had a balcony) presented by Kodak. One of the many fine images we saw was a Fall scene showing Fall leaves, clouds in a blue sky and a river flowing in the foreground. The “without” a polarizer shot was dead and filled with pure white highlights obscuring the leaves colours. The clouds against the blue sky were largely overexposed. In contrast the “Polarized” shot was saturated with colour in the leaves and with fluffy clouds against a rich blue sky. I have had a real affection for polarizers ever since.
Polarizers can also remove reflections from glass at the correct angle, take the highlights from the copy lights away, suppress highlights on painted surfaces… One caveat is polarizers can’t change spectral reflections—reflections from metal for example—because those reflections are at all angles.
Here are two shots taken with a point-and-shoot with the Cokin B160 held in front of the lens. The FujiFilm Z10 FinePix digital camera used has a built inside zoom, so holding the filter against the camera is easier than some cameras. Nothing else was done to compensate for the X 3.5 filter factor mentioned earlier, the camera handled it all.
Finally we are going to explain how important a polarizer is. But first a personal insight. When I was very young, and my family realized how important photography was in my life, my mother took us to a public show in a huge auditorium (it was Eaton’s or Simpson’s and so large it had a balcony) presented by Kodak. One of the many fine images we saw was a Fall scene showing Fall leaves, clouds in a blue sky and a river flowing in the foreground. The “without” a polarizer shot was dead and filled with pure white highlights obscuring the leaves colours. The clouds against the blue sky were largely overexposed. In contrast the “Polarized” shot was saturated with colour in the leaves and with fluffy clouds against a rich blue sky. I have had a real affection for polarizers ever since.
Polarizers can also remove reflections from glass at the correct angle, take the highlights from the copy lights away, suppress highlights on painted surfaces… One caveat is polarizers can’t change spectral reflections—reflections from metal for example—because those reflections are at all angles.
Here are two shots taken with a point-and-shoot with the Cokin B160 held in front of the lens. The FujiFilm Z10 FinePix digital camera used has a built inside zoom, so holding the filter against the camera is easier than some cameras. Nothing else was done to compensate for the X 3.5 filter factor mentioned earlier, the camera handled it all.
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| STRAIGHT |
WITH COKIN B160
Generally, to see where the polarizer’s effect is greatest, you need to shoot in the direction at right angles to the sun. Holding your closed fist up, pointing towards the sun with your fingers and thumb forming a pistol—fingers the grip, pointer finger the barrel and the thumb up at right angles for the pistol’s hammer—with your arm straight and rotating your “pistol” aiming at the sun—the thumb will be pointing where the polarizer with darken the sky the most.
While playing around I tried looking at my LED television screen and rotating the filter. At a very exact angle almost all light is filtered out and you are facing a black screen.
Two polarizers can be rotated to cut off almost all the light getting through. Nobody I know has ever done this double polarizer trick (except for high speed shots of Nuclear bomb tests). Purists would use neutral density filters instead, partially because few people travel with two polarizers (they are more expensive than the average filter).
There is a lot more you can do with a polarizer in combination with other coloured filters shooting Black and White film. For example a green coloured filter might lighten the green foliage while the polarizer would darken the blue sky for a false infrared result.
Years ago I met a lady who had a Canon AE-1. I noticed it had a polarizer mounted on its normal lens. It turned out she had put it on when she bought the camera—almost twenty years before—and taken all her photographs since with it still mounted! Of course this has its drawbacks in loss of light for viewing, focusing and exposure, but it does increase her chances of having stunning results!
While playing around I tried looking at my LED television screen and rotating the filter. At a very exact angle almost all light is filtered out and you are facing a black screen.
Two polarizers can be rotated to cut off almost all the light getting through. Nobody I know has ever done this double polarizer trick (except for high speed shots of Nuclear bomb tests). Purists would use neutral density filters instead, partially because few people travel with two polarizers (they are more expensive than the average filter).
There is a lot more you can do with a polarizer in combination with other coloured filters shooting Black and White film. For example a green coloured filter might lighten the green foliage while the polarizer would darken the blue sky for a false infrared result.
Years ago I met a lady who had a Canon AE-1. I noticed it had a polarizer mounted on its normal lens. It turned out she had put it on when she bought the camera—almost twenty years before—and taken all her photographs since with it still mounted! Of course this has its drawbacks in loss of light for viewing, focusing and exposure, but it does increase her chances of having stunning results!
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