Nice HDR sky envmaps can be found here and P.Debevec also gives access to some light probe images which can be used as sources once converted into OpenEXR. These images must be re-arranged into cubemaps to be handled by HQR, which can be done by hand, or using HDRShop.
Additional envmaps are provided here as OpenEXR cubemaps:
| PRV Gravir | Classical uffizi | Classical Saint Peter's |
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