This bundle contains 12 night HDRIs, 12 sunny HDRIs and 12 sunset HDRIs meant to bring beautiful skies to your Iray renders.  Each image was made at 8192x4096 resolution for plenty of detail and provides all in one lighting/backgrounds for your scenes.  Included are 18 maps high up inside the clouds as well as 18 maps with clouds high in the sky above.  Those "inside the cloud" presets are perfect for tall mountains or towers and flying aircraft or bird renders, while the others are better suited for cityscapes or landscapes.