What is a polarising filter:
Who hasn’t experienced this standing on the most beautiful beaches in the world? The sea shimmers from blue to turquoise in all shades. Almost surreal and you want to capture this image in a photo. Yes, these are the classic postcard motifs. You pull out your camera and take the photo. But what is this ?
None of this colourfulness is to be seen in our picture. Instead, the sky is white, the sea grey with many small reflections of light.
Here we recommend a polarising filter, called a polarising filter for short. It ensures that certain light waves are filtered out of the picture and reflections disappear. In addition, the colours appear stronger. However, a polarising filter also darkens the subject by one f-stop.
The effect of a polarising filter can perhaps be explained using a comb. If you hold a comb horizontally in your hand, the teeth point downwards and let the vertical light rays through. If you hold it vertically, however, the teeth point to the right or left and the horizontal light waves are let through. It is similar with the polarising filter. Once it is screwed onto the lens, you can turn it and filter out vertical or horizontal light waves. The effect can be seen very well through the viewfinder.
There are also considerable differences in the price of polarising filters. The mode of action is not very different in the various price classes. However, cheap polarising filters can impair the sharpness of an image. Especially at long focal lengths. I personally use the Hoya Pro1 Digital Pol Cirkular 77mm.
Besides a beautiful picture of the turquoise-blue sea, the use of polarising filters is also recommended when photographing other reflecting or mirroring objects. Especially in architectural photography, with large glass facades, it often happens that you get a completely different image expression with and without reflection. Or with rainbows, you can use a polarising filter to make them disappear or intensify them, depending on the rotation of the polarising filter.