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View Full Version : Eliminating Glare and B&W Film: Polarizer vs Red Filter?



Michael Heald
11-Feb-2007, 14:39
Hello! I've read that a polarizer darkens the sky in B&W film much like a red filter. Recently, I shot a building with a polarizer and 4x5 100G and a #25 red filter and 4x5 TMax 400. I was surprised that the color film/polarizer combination seemed to show more texture in the building's concrete surface than the TMax/Red filter combination.
As I thought about this, it seemed to me that a red filter darkens the sky but doesn't eliminate the glare from surfaces (even minor glare such as from white concrete), since a red filter isn't designed to eliminate polarized light, but to transmit light within a given frequency range.
Would it be beneficial to shoot B&W film with a polarizer as well as a colored filter in order to minimize this minor glare and improve the reproduction of texture on B&W film? If so, is there a recommended order to place the filters - colored filter or polarizer first? Thank you and best regards.

Mike

Walter Calahan
11-Feb-2007, 16:10
The "glare" you are seeing is polarized light. No amount of red, orange, or yellow filters will affect this type of light.

If you want to stack filters, put the red on first, and then the polarizer on top. This will make it easier to turn the polarizer to get the effect you want.

Bottom line is experiment so you discover the answer to your question. That way you'll truly learn, not simply do what someone else is doing.

Glenn Thoreson
11-Feb-2007, 17:50
Unless you want really dark skies, the red filter is rather overkill. The polarizer will eliminate glare from surfaces other than metal abd deepen the sky, to. There is no practical way to eliminate glare and hot spots from metal surfaces, because it's not polarized light. You will see improved detail in some surfaces, even vegetation, with the polarizer. Red is good for getting detail in aged wood, stone and masonry, if it's side lighted.

Michael Heald
12-Feb-2007, 08:19
Hello! Thank you for the reply. I've been using yellow, red, and green filters to increase what I would call large scale contrast in B&W. I was surprised to see additional detail in the white concrete and stucco that I photographed with the polarizer. I would call this texture local contrast for no better term, unless others have a better term that is used for this.
Since the polarized light and and resulting glare rob high values of detail, I imagine a polarizer colored filter combo would be useful for a photograph that has important non-cloud/sky highlight areas. Best regards.

Mike

Ed Richards
12-Feb-2007, 09:58
The more narrow the field of view, the better the polarizer works. With wide lenses it can be uneven, so the red may work better. I had not thought about a yellow and a polarizer, so you get some reflection control plus some darkening.

Ken Lee
12-Feb-2007, 10:10
http://www.kenleegallery.com/images/gallery/cornfield2.jpg

Medium Yellow plus a polarizer works very nicely - especially when you are shooting at a right-angle from the Sun. (That is where the polarizer will give its maximum effect).

The yellow color (as opposed to red/orange) will actually lighten some of the vegetation, rather than darken it - which is nice if your subject contains vegetation. When the vegetation contains a variety of shades, this will bring out the texture.

The other nice thing about the polarizer, is that you can rotate it, and control the darkness of the sky, according to taste.

C. D. Keth
12-Feb-2007, 10:25
They do different things. You can't compare a filter that passes a narrow band of the spectrum with one that passes a certain polarity of total light.

Aaron van de Sande
12-Feb-2007, 10:53
Maybe this is true out west, but on the east coast it can be pretty hard to get a sky when it is humid out.


Unless you want really dark skies, the red filter is rather overkill. The polarizer will eliminate glare from surfaces other than metal abd deepen the sky, to. There is no practical way to eliminate glare and hot spots from metal surfaces, because it's not polarized light. You will see improved detail in some surfaces, even vegetation, with the polarizer. Red is good for getting detail in aged wood, stone and masonry, if it's side lighted.

Ed Richards
12-Feb-2007, 11:00
> Maybe this is true out west, but on the east coast it can be pretty hard to get a sky when it is humid out.

Same with the Gulf Coast. I have a 29 Red for those days. Costs 4 stops, but it can bring contrast even in an overcast sky, if there is any blue at all.