I have spent some time photographing landscapes with blue sky and white clouds, but the clouds always come out overexposed. I have tried different settings and still have the same result. What should I do to get correct exposure?
If you are just pointing your camera at the sky and getting just sky and clouds in which are overexposed, you can increase your shutter speed to decrease the exposure, lower your fstop (make the aperture number bigger) or decrease your iso if it is too high to fix these problems. You will need to be in manual mode to control that properly.
If you are having problems where the sky is overexposed in relation to something in the foreground, the classic being a landscape photo. You have a couple of options:
- Graduated Neutral Density Filters: these have a dark section sort of like sunglasses that will allow you to balance the difference between the brightness in the sky to the land. http://www.flickr.com/photos/awfulsara/51300446/
- HDR - High Dynamic Range images when done properly allow you to get past the short comings of digital sensors and capture the whole range of bright and dark areas (dynamic range) of the image across multiple exposures. http://www.flickr.com/photos/farbspiel/4760195930/
- Don't expose for the foreground which will give you a dark foreground but will keep your clouds in check. http://www.flickr.com/photos/paslematin/3971343610/
- Watch the time of day you are shooting: A lot of landscape people talk about the "magic hour" which is the hour before and after sunset or sunrise which is when the sun being low to the horizon reduces its intensity, allowing more dynamic colours to show and removing the harsh sunlight from the sky. This still makes it very hard to evenly expose for the ground and the sky but is when it is easier to get a more pleasing photo. http://www.flickr.com/photos/thereal7/3498060183/
You can use a graduated neutral density filter, which will reduce the exposure of the sky without reducing the exposure of the foreground.
Lots of great options in other answers, so I'll just add one more.
If you're shooting in RAW and your sky is overexposed but the highlights aren't blown out, then you can replicate the effects of a GND filter to a certain degree digitally. In a tool like Lightroom, you would simple drag the filter from the top to the bottom and adjust the levels.
(@Francesco briefly mentions this, but I thought it deserved more.)
Even better is to use tone mapping to level off the differences in brightness. This is usually done to HDR images, however, because the dark areas tend to be noisy without extra exposures.
What is happening is that you are exposing for the foreground and overexposing the clouds in the process. If you expose for the clouds, the rest might come out underexposed. You can try two techniques:
- HDR: Take at least 2 pictures, one exposed for clouds, and another one exposed for the foregorund and then combine them. Can take multiple exposure between these two ones if the difference is a lot.
- GND: This will set the exposure of the clouds to be few notches below your foreground.
You could set the meter to Spot and evaluate the clouds. Then (in manual mode) recompose with those settings, without worring if now the meter is signaling under exposure (which will probably happen since the clouds are brighter than the earth). Obviously this assumes that you can accept this relative under exposure.
Or you could use a filter to reduce the amount of light coming from the upper region of your frame (this effect can be replicated in software like Lightroom, Photoshop or Gimp).