The worst that can happen, is a strong backlight, rendering the front subjects in dark shadows, and everything else in the background overexposed and burned out in highlights. This is especially true in street photography, you cannot relocate your subjects (I advice not to do so, but if you must, feel free to practice your own style), you cannot change the available light situations. Yet, some subjects are worth shooting despite the crappy light: interesting character in a portrait, which I have encountered so often.
Therefore, I would like to share how I deal with difficult lighting conditions when I am out doing my street shooting, especially when it comes to strong backlight. Kindly take note that these are my own shooting preferences that fit my personal photography style, they may not work for every one.
1) Expose Your Subject. Ignore The Rest
In uneven, challenging lighting conditions, you must be very clear of what your main subject of the image is. I always emphasized on that particular subject and made sure that the metering on that subject is correctly exposed. I basically tuned the exposure compensation, and worked with the WYSIWYG (What You See Is What You Get) live view, or through electronic viewfinder to judge the exposure. I can forgive an overexposed background, as long as my main subject, usually a portrait of a stranger, is in neutral and balanced exposure.
2) In Extreme Backlight, Play With Silhouette Effect
There are times the backlight is so strong that all you get is shadow figure in the foreground, which is not necessarily a bad thing. Creative play of highlight and shadow can bring interesting results. Using the extreme backlight to your advantage, you can purposely throw your main subject into dark shadow, creating a silhouette output which can yield desirable outcomes too. Not everything needs to appear perfectly balanced.
3) Black And White Works Well With Uneven Lighting
Converting an unevenly lit image into black and white can often change the overall presentation of the image altogether. High contrast black and white images work well with images having strong light sources, and the burned highlights and deep shadows added much needed grittiness to the images, especially when it comes to street photography. I am in no way implying that you can salvage a badly exposed image by turning it into black and white, no, if the image is bad, it will be bad regardless the color or monochrome presentation. In some harsh light, black and white can provide an alternative look that could prove more exciting than full color reproduction.
Silhouette Works With Strong Backlight
Black And White Complements Harsh Light And High Contrast Scenarios.
4) Shoot in RAW and Use Highlight/Shadow Recovery
If you are a RAW shooter, you should know how much details you can actually recover from the burned out highlights, or from the deep shadows during post processing. If you are a JPEG user, when you encounter such extremely difficult lighting, you may want to start to consider the advantages of shooting RAW. I am not asking you to ditch JPEG. In difficult circumstances, RAW can actually save lives, and it would be foolish to ignore the full potential of your camera. Any modern camera these days come with RAW shooting capabilities, which record and store far more information in the image file, that can be pushed and pulled during post processing. Simple sliding of highlight and shadow sliders in post-processing software of your choice can make a huge difference.
JPEG image, with overblown overexposed background
RAW image, same shot from previous JPEG, but processed, with simple highlight recovery
I acknowledge that there are numerous methods out there, some rather effective to counter backlight, or uneven lighting. Using large reflectors can balance the subject against harsh background. Also, a popular use of fill in flash can also mitigate faces in deep shadows. Alternatively, there is the ever-frowned upon HDR technique, which, honestly, if done correctly and tastefully, can give you some impressive results.
For some of you newcomers to photography, I sure you found some of the tips here helpful!