HDRI environments for D5 Render

Load an HDRI in D5 Render 3.1

1. Open the Sky Light settings panel.
2. Select the HDRI option to expand the HDRI parameters.
3. Open the HDRI dropdown, choose "+Customize HDR" and select the .hdr or .exr file. D5 saves custom files into the "customhdr" folder under the D5 installation path, reachable from the folder icon in the panel; keep the path free of special characters, otherwise D5 reports "Failed to load HDRI".
4. Set Rotate to align the sun and reflections with your model, and use Flip Horizontal if the scene reads mirrored.
5. Adjust the Light slider for overall HDRI brightness, and set Skylight and Background separately if you want a brighter interior fill than the visible sky.
6. Turn on Custom Sun only if the HDRI has no clear sun disc; an unclipped sky HDRI does not need it.

Try before you buy: the free HDRI samples need no account and carry the same licence as the paid files, so you can check the setup above with a real file before buying.

D5 Render accepts .hdr and .exr files as spherical (equirectangular) panoramas with a 2:1 aspect ratio and the horizon at the middle of the frame.

Which resolution

D5's documentation does not state a fixed pixel limit for imported HDRIs, only that the render resolution itself can be set to 2K, 4K, 8K or Actual Resolution in Preferences > Rendering. For lighting only, a 4096x2048 to 8192x4096 HDRI is enough; for a sky the camera sees directly, use 16000x8000 to 20000x10000. Because D5 is a real-time GPU renderer, keep files at 8192x4096 or 10240x5120 for typical walkthroughs rather than the full 20000x10000 set.

Sun and shadows

Use one of HDRI Hub's 34 unclipped skies so the sun disc is intact and casts a defined shadow instead of a soft, clipped one. With Skylight and Background brightness balanced, the HDRI is the only light source needed; leave Custom Sun off.

Frequently asked questions

Does D5 support .exr HDRIs?

Yes. D5 documents both .hdr and .exr for custom HDRIs, so every HDRI Hub sky loads without conversion.

Why is the sky blurry in the viewport?

D5 compresses the HDRI for viewport speed. The output resolution follows the HDRI Resolution setting under Preferences > Rendering (2K, 4K, 8K or Actual), so the blur is not a defect of the file.

Skylight or Background?

Skylight sets the diffuse lighting the HDRI contributes, Background sets how bright the visible sky and reflections are. Lower Background to recover sky colour, raise Skylight for a brighter interior.

Should I enable Custom Sun?

Only when the HDRI has no clear sun. With an unclipped HDRI Hub sky the map's own sun casts the shadow; a Custom Sun on top produces a second, mismatched shadow.

More background: which HDRI resolution you need and .hdr or .exr.