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• Ptex may break on Loop subdivision meshes that are visible in render and are destroyed by a plugin using the Subdiv API

• Rendering an alembic file with any instances will only render the original geometry. The procedural does not call ObjectBegin/ObjectEnd or ObjectInstance so all instances are ignored.
• Full LPE support is only available with the PxrPathTracer and PxrVCM integrators.
• Cryptomatte
• Crop renders write the whole image with black padding. These will still be correctly aligned with the main render.
• Single-scatter volumes show as an opaque volume envelope. Multi-scatter volumes work correctly.
• Checkpointing is not currently supported.
• Cannot be used with another sample filter such as the implementation of Maya's Image plane.
• Light Filters in the PxrVCM integrator do not affect or shape photon emission.
• The Cone Angle parameter for lights is incorrect, it does not match the input angle, this will be fixed in a future version.
• The PxrAovLight does not work properly with PxrUPBP.
• Analytical lights placed inside volumes may yield artifacts when made visible to the camera. As a workaround, the light camera visibility should be turned off, and a geometry with a similar shape should be used (visible to the camera, invisible to transmission and indirect rays), with the proper emissive bxdf.
• Using the '.' character in the handle for an OSL shader could cause unpredictable results during re-rendering.
• Instances are not supported for baking.
• 3d baking: no direct bake-to-ptex support.
• PxrBakePointCloud cannot directly render ptex.
• No RixPTC/pointcloud API (so PxrBakePointCloud cannot read ptc files).
• Sample/Display filter plug-ins do not have access to lighting services for light dependent effects, e.g. lens flare.
• Adding new mesh light on existing geometry during IPR results in double geometry.
• Camera visibility changes are not respected during Live Rendering.
• For PxrUPBP, If the light source is inside a volume, that volume needs to be defined as Volume “box”, RiVolume
• For PxrUPBP, To get a volume caustic, the object casting the caustic needs to have higher intersectpriority than the volume.
• For PxrUPBP, Overlapping heterogeneous volumes are not working yet. (However, overlapping homogeneous volumes do work.) This will be resolved in the future.
• When attempting to access an array primvar, you must first check the size of the array primvar and allocate the appropriate space. Not doing so may lead to a crash.
• Points and curves cannot have mesh lights attached to them.
• Deformation motion blurred volumes don't currently work with densityFloatPrimVaror densityColorPrimVar. You will need to use a PxrPrimVar node connected to densityFloat and densityColor instead.