How to avoid washed out highlights
The first rule or the golden rule should I say, is to always expose for the highlights.
Most of the time, when a shot is underexposed, you can recover details in the shadows in your editing programme while nothing can be done if the details are not there in the first place!
And that's what happens with washed out highlights! If your whites are burnt out, it's ruined!
There are a few basic things you can do to avoid that:
When shooting in bright light, and especially for landscapes, the use of a polarizing filter or a neutral density filter can help a great deal.
A polarizing filter will also give your skies beautiful vibrant colours while neutral density filters will give your shots a subtle and warm toning.
Using these kind of filters will set your exposure a few stops down which might prevent washed out highlights.
If you don't have a polarizing nor a neutral density filter, simply set your exposure a few stops down (underexpose) to avoid overexposure.
For other kind of photography, such as still life or portraits where the use of a polarizing filters is not recommended and quite useless, simply set your exposure a few stops down.
Underexposed: -1/2 stops
Overexposed: +1 % stops. (all details in the whites are lost)
If your subject is backlit, use your flash!
It will darken your background avoiding your main subject to be underexposed and your background to be overexposed.
It's better to underexpose than overexpose!
Underexposure can almost always be fixed when editing your images.
Overexposure rarely can.
And one of the most important and fantastic tool is the histogram!
If your camera has that option: USE IT!
It will tell you straight away if your highlights are washed out!
If the right end of your histogram is touching the wall, delete the shot and try again until you got it right!
The right end of the histogram represents the highlights. If the curves are against the wall, it
means that all the details in the whites have been lost.
Highlights. (clipped: no details in the whites)
The left end of the histogram represents the shadows, or the blacks.
If it touches the wall, it means that all details in the shadows have been lost but most of the time, some details in the shadows can be recovered by using the dodge tool or/and by adjusting the levels and contrasts.
Shadows (clipped: no details in the shadows)
The histogram is your best friend when it comes to exposure!
And remember, trials and errors are still the best way to learn!