HDR skydome in .hdr format to use as a spherical environment in 3d scenes. The HDR has a very high dynamic range for great looking realistic shadows from the sun, and great cloud details.
6000px wide, it is great to use as the actual background. When you import in your 3d package use a liniar color profile for a more even light, or use a sRGB profile to get a dramatic sunset look.
Hope you enjoy and please rate.