Camera electronics can suffer heat damage.  Digital cameras may suffer electronic damage if temperatures rise too high.

Heat can also cause greater image noise with Digital cameras.  This is like adding fog to an image.  Keep equipment protected from excessive heat.  Image quality is at stake.  Click Here for more about Digital Image Quality and Noise.

Film also suffers in hot conditions.  Prolonged exposure to high heat can deteriorate film emulsions resulting in film fogging (slight overall film exposure) which will diminish contrast and color quality.  The plastic material used as the base for the emulsion suffers in high heat just as any plastic.

A little care in protecting cameras, lenses and film from heat extremes will save disappointment and potential damage.  Simple shade can make a big difference.  Allowing a little ventilation to the space where your photographic equipment and supplies are stored can help moderate temperature extremes.  If possible, insulate your gear and film to hold heat at bay.  If nothing else, avoid direct exposure to sun light under windows.  Remember, even on relatively cool days, cars can get very hot, very quickly when parked in full sun.  The green house effect of closed windows rules!

Light
Almost like the bright white snow of winter, bright surfaces under summer sun can 'fool' light meters and automatic cameras.  The can be subjects looking too dark. Camera exposure systems, and light meters “see” the bright scenes as medium gray. Light readings directly from bright scenes result in underexposing the scene. Compensating for this potential exposure error simple requires a wider lens opening or longer shutter speed.  Manual cameras can be set to the wider opening of between 1 and 2 f-stops. This range usually suffices. Most automatic cameras have an exposure compensation feature +/- that can be set to accomplish a similar result.  Refer to your user's guide to see if your particular model has this setting, and where to find it.  Look for this symbol , and set the exposure compensation lower, to counter extremely bright light.

Outdoor Photos in Bright Light
On bright days, extra light enters your camera and can produce odd light patterns such as hexagonal shapes over your image or a loss of image contrast. This occurrence, known as flare, can happen even if you are not shooting directly into the sun. To help prevent flare, find some way to block the stray light. Try shielding the camera with your hand or hat, or moving your position so a tree branch obstructs the direct sun.

Landscape Shots - Shadows
During summer, mid-day sun shines high in the sky.  This causes hard shadows very close to subjects.  Morning and late afternoon light cases longer shadows with slightly softer light ratios between light and shadow. 

Generally, the softer, longer shadows of early and late day lighting produce more pleasing results than mid-day conditions.  The effect of morning and late day out-door lighting creates greater color and texture contrast much like the softer quality of Autumn and Spring-time natural light.  By comparison, the strong down-light of a mid-summer day produces a stark look to the scene.

Create intriguing, contrasting images by using natural shading in part of the scene.
Use shadows caused by trees, large bushes, cliffs or boulders.

When the sun is lower, as in early morning or late afternoon, shadows are longer and easier to find.

Clouds provide great shading, especially on sunny days where even a single cloud can cast an interesting shadow on part of a bright landscape scene.

Be careful that the shadows don't cause your camera's metering system to overexpose your photos, particularly when using a digital camera.