HDR stands for High-Dynamic-Range. Many phone cameras have it and it can come in handy depending on the picture you want to take. Instead of taking one photo at a set exposure, it takes three at separate exposures then merges them together to make a great overall photo.
Why is it useful?
In pictures where the sun is being shown, it can allow you to see the sky as well as the subject, not just either or. Overall it can even out the light distribution to create a better picture that shows all parts. Some pictures where it is mainly composed of mid-tones, using HDR might not come in handy or work at all.
How do I use it?
On your phone camera, you just need to look for "HDR" if it is present on your phone. It is usually optional or auto depending on the phone brand. It is not the most common but with point-and-shoots and DSLRs it possibly can be found. For those you will need to check your camera for but it is possible that it might not be present.
To the left is a more professional example of HDR in use. (Click on it for original Link) The three pictures below it ate the ones that were used to create the larger picture. You can see the separate tones that were taken to create the visually stunning picture you see in the end.
I know Jordan both on a personal and professional level, in both cases a wonderful guy. While acting as one of his models he was incredibly pleasant to work with. He has a vision and will try to fulfill it, while always taking the opinions and visions of others in equal regard. He has an amazing eye for great shots and is extremely talented.."
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