I really like work with a polarizing filter. It allows me to take very interesting photos that I can hardly get when postprocessing photos taken without this filter. When buying a polarizer for a digital camera, it is important to buy a circular polarizer because digital cameras may have problems with autofocus or setting exposition values if you use linear polarizer. But I did not tried it, because I don't have a linear one. But the most important is what polarizing filter can do for us:

• remove reflections from non-metallic objects
• darker sky with highlited clouds
• more saturated colours

Remove reflections

Polarizer is used to remove reflections from a non-metallic objects like water, leafs or glass. Sometimes there is a problem with glass, because most modern windows are coated with metal foil. Effect of removing reflections from water is shown on pictures below.

Photo of water
taken without a polarizer

Photo of water
taken with a polarizer

Darker blue sky, hightlited clouds and brighter colours

Polarizer eliminates reflections on small water parts in atmosphere which results in darker blue sky with nice white clouds on it and brighter colours of distant places. There is one very important thing - orientation to the sun. The effect is better when you turn 90 degrees from the sun, when you have sun in front or behind you, this effect will be nearly invisible. Both effects are shown on photos below. Both photos was taken from nearly same place.

Photo of scenery taken
with polarizer

Photo of scenery taken
without polarizer