Summer can be hot here in Australia, and today it is supposed to reach 41°C and trying to get a decent photo during much the day just results in a totally bleached out sky. There are basically three solutions-
- Only Photograph during the golden hours in summer.
- Take separate photo just of the sky and using blending, masking and compositing insert a sky during post processing.
- Use a Polarizing Filter
The first option is a bit restrictive, and the second can be a lot of work. I have an old circular polarizing filter it is designed to rotated when screwed onto the front of your lens. I find it pretty much indispensable for any daytime outdoor photos in summer. The polaroid sunglasses use the same principal of filtering sunlight and other strong light source which have reflected off a surface (including the earth atmosphere) and only the light with a particular direction of vibration is reflected so the light is polarized. A suitable filter can reduce this light when place at right angles to this preferred direction (its fairly technical physics) but is easily exploited. Those sunglasses have the polarised direction set to cancel out reflected light off water or surface. The circular polarizer is more flexible on a typical DSLR as you can rotate it to any angle and see the result in the viewfinder. The results are most noticeable at right angles to the sun. There is a good tutorial on using a polarizing filter by Cambridge in Colour.
Because the polarizer is removing light (in specific directions) it acts a lot like a neutral density filter making the exposure longer, diffusing the harsh contrast a little and frequently enhancing the colours a little.
A circular polarizing filter is almost a necessity in an Australian summer