A polarizing filter will be capable of its maximum effect when one's line of sight in red below is perpendicular to the direction of the sun:. The red disks represent the directions of maximum polarizing capability. A good way to visualize this is to aim your pointer finger at the sun while holding your thumb straight up. Everywhere your thumb points when you rotate your hand while still pointing at the sun is where the polarizer is capable of the strongest impact.
However, just because the filter is capable of its maximum effect in the above directions, this doesn't necessarily mean this is where the image will appear most effected. Rotating your filter will toggle the angle relative to the sun that appears most polarized. The best way to get a feel for this is to rotate the filter while looking through the camera's viewfinder or rear LCD , but you can also consult the box below for specifics on how this process works.
Notes on Filter Rotation Angle. At one extreme, you can rotate your filter so that the direction of maximum polarization will be perpendicular to the direction of the sun as shown in the above examples. In that case, the polarizing effect will be as pronounced as possible. As this angle gets progressively closer to the direction into or away from the sun, the polarizing effect will appear progressively less pronounced.
Any more rotation than this and the polarizing effect increases again and the cycle repeats. Since a polarizer's effect varies with angle, results can appear uneven when using a wide angle lens. Some portions of the scene might be in a direction which is directly into the sun, whereas others might be at a right angle to the sun.
In that case, one side of the photo would have a strong polarizer effect, whereas the other side would not. In the example to the left, the sun was near the horizon, so the strip of sky directly overhead was most influenced by the polarizer causing it to appear darker , whereas the upper left and lower right regions nearer the horizon were much less impacted. If a telephoto lens had been used to photograph just the tower, then the sky would have appeared much more even.
Although wide angle lenses certainly aren't ideal, rotating the polarizing filter can sometimes make the effect appear more realistic.
One approach is to ensure that the most pronounced polarization coincides with the image's edge or corner. This way the change in polarization will look more like a natural gradient across the sky such as how the sky might appear during twilight.
One of the first characteristics that you're likely to notice with polarizers is how they increase color saturation :. When direct reflections are reduced, a greater fraction of the subject's light is of the diffuse variety — resulting in a more colorful representation. Foliage will be rendered with a brighter green, skies will have a deeper blue and flowers will appear more intense.
The average is slightly different between linear polarizers and circular polarizers. You can learn more about the difference between linear polarizers and circular polarizers here. When you rotate linear polarizing filters, you also adjust how much of the light reflected you can block out. The maximum polarization effect is achieved when the lens is pointed at 90 degrees to the sun or light source, and can sometimes be affected by your depth of field.
To achieve this, make an L shape with your first finger and thumb, pointing the thumb at the sun or light source. Where your pointer finger rests will indicate where the polarizer has the optimum impact. Share this story Facebook Twitter Copy link. Everything you need to know about exposure compensation when using a polarizing filter.
So, once the filter is secured to the lens, the front part of the filter will rotate freely. It is this rotation that will allow you control the polarization effect. By looking through your viewfinder or at your screen begin rotating the filter until you get the amount of reflection removal you need. Depending on the lighting conditions the effect may be dramatic or subtle so really pay attention to the details and the areas that are most important to you to control.
Below are examples of common subject where a circular polarizer is used. A circular polarizer darkens blue skies and helps bring out clouds. This helps during both blue sky days as well as cloudy sunsets and sunrises. A polarizer helps reduce the glare so that you can see the true color of the water, as well as see through to some of the rocks or other details below the surface of the water. Leaves from trees and bushes hold glare, especially when wet.
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