effective polarizer usage?

Question

i just got a polarizer filter and i read somewhere you have to up the exposure by one or two notches. what does this mean? my last roll of film looks unaffected by the polarizer.

Answer 1

Hoping to not hurt tigerrrgrrl's feelings I must say she is wrong on several points.

First, a circular polarizer is used by film and digital cameras. Why not a linear polarizer? Because a linear one will interfere with through the lens metering and auto focus. The linear polarizer is recommended for cameras without AF or through lens metering although a circular polarizer will work equally well.

Second, to get maximum benefit from a polarizer you want the sun on your shoulder. Pretend you're standing on the face of a clock facing 12. With the sun at between 8 & 10 or 2 & 4 but especially at 9 or 3 you'll get maximum darkening of the sky for a dramatic deep blue. You may have to turn slightly one way or the other to fully achieve maximum polarization. Simply turn it until the sky darkens in your viewfinder.

The polarizer is also useful for eliminating glare/reflections from water, sand, snow, glass and painted metal - but not polished metal. It can also enhance colors in flowers.

Using a polarizer on extreme wide angle lenses is problematic. Part of the sky may remain lighter than the rest.

Answer 2

With almost all filters there is a bit of light loss (ie, the filter blocks a small amount of light). If you have an SLR, it should meter through the lens so you really don't need to worry too much about that. You're shooting film, so I must ask, are you using a circular polarizer or a linear polarizer? Circular is mainly for digital where as linear is for film. Results are most apparent when shooting a bright blue sky or green grass. Try putting your polarizer on your camera and pointing it at a blue sky. Then take the polarizer off and look at the same sky. You should see a difference through the viewfinder. To get the most effect in the sky, make sure the sun is behind you.

Answer 3

If you want all the bla bla bla, visit:

http://en.wikipedia.org/wiki/Filter_(photography)

Pola filters are great tools for many things.. if you want to capture a face inside a car.. if you want to avoid sun rays, if you need to emphasize clouds.... is endless...

Tip: just place the filter, and slowly rotate it looking towards a windowed subject..... or just take the filter for a walk into a parking lot and stare at the car windows moving 45 degrees the filter... then you will know!