Set up your scene using shaders which aren't too reflective or shiny. This one uses the default shader with the colour changed to almost white and the shininess reduced to zero. Delete all lights from your scene and reduce ambient light to zero. You don't want any other lights if you're using HDRI. Load an hdr file. Choose one which is close to or all greyscale - bright colour will effectively light your scene with coloured light. I used the mono snowfield one that came free with C3 for this image. Flip to the Render room and turn on Full Raytracing, Sky Light and Indirect Light. Turn off Interpolation and Transparency. Set the various quality setting as high as you like; this image used Anti aliasing: Good; Object & Shadow Accuracy: 1 pixel; Lighting Quality: Good & Accuracy: 2 pixels. Do a test render. If the scene is too dark or too light flip back to the Assembly room and adjust the HDRI intensity. This image used a setting of 175%. HTH Mark