You can use the iPhone 4's HDR (High Dynamic Range) capability to take pictures under sub-par conditions (too much or too little light). When you turn HDR on, your iPhone will take three pictures in quick succession with different exposures and then blend them together to produce the best image. Here's how to use it:
- Open the Camera app.
- Tap on HDR at the top center of the screen to turn it on (tap again to turn it off).
- Tap on the bottom-center camera icon to take a picture. Stay as still as you can while your iPhone takes three consecutive images.
By default, the Camera app saves two versions of the image on the photo roll: a regular version and an HDR version. If you want to only save the HDR version, open Settings>Photos, and slide Keep Normal Photo to the OFF position.
Turn on the HDR feature even if you're unsure you need it
If you notice the lighting could be a little too dark or too bright for a picture, turn on the HDR feature. Since this feature saves two versions of the photo in your Camera Roll, you'll get to choose which image looks the best and use it.