Backplate.

[raymondwganderson]

Hello folks, is there any way in Arnold Render to apply a different Backplate image from the HDRI that lights the model?  ie Scene / Model lit with a specific HDRI but using a backplate from a different HDRI. [ see attached model ] I want that lighting but a different backplate [ I have 1 in mind ]

[wernienst]

Yes, that's possible. Open Render Setup, Arnold Renderer tab, go down to Background (Backplate), change Source to Custom Map.

[raymondwganderson]

@wernienst  Many thanks for the info. Still having problems though. I have used a jpg as a backplate as I dont have it in png. [ not sure if that makes any difference though ] as you will see The floor of the hdri is still visible and the backplate seems too small and very faint  [washed out].  I used a bitmap node from the material editor and used it for the backplate. I am quite obviously going wrong somewhere. see attached.

[wernienst · Accepted solution]

For both Environment and Backplate map you should choose Spherical Environment as Mapping.

The file type doesn't matter (I think). You may add a Color Correct node to adjust brightness/contrast. However, if the Environment map is also used for illumination, it should be a real 32-bit HDR map. And you should add an Arnold Skydome Light and assign it to its Texture channel.

[raymondwganderson]

@wernienst , Apologies for the late reply , Thanks to your help I have now managed to sort out the backplate. Another aspect learned. Attached is the look that I want [ although I would like my render to be a wee bit sharper,  that will be for another topic though ] this is done using the default Arnold render settings.  Many thanks.