Project 35: using a polariser

I actually took the photographs for this assignment before I completed project 33 on using a tripod.  As I was out hill walking I fell into the trap of being lazy as I explain in the blog for Project 33.  It is all too easy to decide to leave it in the car when I am carrying a heavy rucksack anyway.  I feel even more humbled when I think of the heavy loads carried by Ansel Adams and Joe Cornish.  I must get into the habit of using my walking pole which has a tripod bush in the handle.  All I would need to carry then would be my lightweight tripod head.

For the first part of the project I took pictures when I was out walking with my brother in Derbyshire on Derwent Edge above Ladybower and Derwent Reservoirs.  It was during a cold spell and we had had snow but this morning dawned bright and bitterly cold.  Kinder Scout was on the horizon at right angles to the sun with a bank of cloud just above the horizon so perfect for using a polariser.

For the second part I was out walking in the Lincolnshire Wolds and came across a trout lake which fitted the bill perfectly even down to the rocks under the water.

I images are shown below:

85mm lens setting

As we climbed up onto Lost Lad I noticed that there was a lovely bank of cloud hanging above Kinder Scout on the horizon and at right angles to the sun.  For this picture the polariser was rotated so it had no effect.

The difference in this second image is amazing.  Here I rotated the polariser through 90 degrees to get the full effect.  The sky is darkened and the clouds stand out beautifully.

17mm lens setting

Using the same view I set the lens to its 17mm setting and rotated the polariser so it had no effect.

Here the polariser was rotated to give the full effect and this is very noticeable.  The clouds stand out and the sky is very much darkened to the right of the shot on the side furthest away from the sun.  At this wide angle setting the lens covers more of the sky, including areas closer to the sun where the light is not polarised.

Photographing water with a polariser.

In this shot of a local trout lake in the Lincolnshire Wolds I rotated the filter so it had no effect.

In this shot, where the filter has been rotated to maximum effect it can be seen that many of the surface reflections have been removed and the rocks and detail on the bottom of the lake can now be seen more clearly, particularly in the foreground.

What Have I Learned
A polarising filter can be used judiciously to darken a blue sky, bring out detail in the clouds and increase saturation in the image.  It can also reduce reflections on water.  It can, however, be overused, especially with a wide angle lens where the effect is uneven.  It works best with standard focal lengths to medium teleohoto.  The best effect is seen when facing at right angles to the sun and there is litte effect when in line with the sun.  To my knowledge it is one of the few, if not the only filter, whose effect cannot be duplicated in today's processing software packages.