In the AOV tools rollup of the AOV Scene Settings dialog, you can find the Light mixer tool.
This create an AOV output usable in the render
It scans all the objects of the scene, and list the light Ids actually used.
This include all Octane lights, as well as all objects using an Emission texture in their material.
The Light mixer dialog has several options to customize the creation of the layers:
-Include passes: Choose witch type of light passes to include, as well as some other specific passes (Post processing, Background for background image)
-Light IDs from scene: get the light IDs to include by parsing all objects of the scene.
This will add the corresponding passes for objects that are currently visible.
Use Refresh button when you change objects visibility, or add/delete light objects.
-Light IDs : if 'Light IDs from scene' is disabled, you can choose the light IDs to include manually.
-Light passes: You can also include the Direct and Indirect light passes.
-As layer : create a single AOV output with layers for each light pass ID / special pass
-As Outputs : create one AOV output for each of the light pass ID / special pass
Pass list :
Show the passes that will be included in the created AOV output.
Note that the Background is not a regular 'pass', so it doesn't appear in this list.
You can use the context menu to highlight the corresponding objects in the Light object list, or select them in the scene.
Light object list:
This is the result of the scan of all the scene objects.
All visible objects using light emission will appear here.
Use the Refresh button to re-scan the scene.
You can use the context menu to select objects in the scene.
The 'Create AOV light passes button will create or update an AOV output named 'LightMixLayers' (when 'As Layers' is selected).
Note if you change the light list and press the 'Create' button when a 'LightMixLayers' output already exist, this will automatically update the output with new layers,
but unused layers will not be deleted. You may prefer to Remove or rename the 'LightMixLayers' output.
When rendering with the Octane Viewport, you can now choose the 'AOV xx (LightMixLayers)' as a render pass, and enable / disable each layer to examine your lights settings.
Note the context menu (right click) on the Enable check box for the layers, with options to enable only one, all except one or all layers.
---- Background layer -----
An Image AOV output is used to add a Background layer, matching 3dsmax viewport background image.
The 'Use Viewport background' check box should be enabled, to get the image from the viewport setting, instead of the filename button.
The 'Resize type' should be set to 'Auto fit' to use the 'Aspect Ratio' from the viewport setting (match Viewport, Bitmap or Rendering output)
The 'Unfiltered' checkbox should be disabled, unless you are using an EXR image, that may fail to be resized in some cases.
The 'Save scaled image to file' should be disabled, unless you want to re-assign the image / animated images once your output size is fixed, to avoid further rescalling.
Animated background images are supported with the .ifl format (list of images).
The default setting when using the Light mixer with a background image will use the bottom layer (Layer 1) as an AOV image,
and the next Layer (Layer2 ) will be set to use 'Normal' blend mode, instead of the default 'Add' blend mode.
If you re-order or change the next layer, remember to set it as Normal blend mode.
The Alpha channel should be enabled in the Kernel / Kernel type setting of the Render setup dialog.
Note that the previous way to display the 3dsmax background should be disabled ('Use viewport background' in the Kernel / Render view Settings of the Render setup dialog).
This is limited to a full view scaling, witch didn't match 3dsmax viewport, and is not exported to orbx.
The new AOV image has a correct scaling, and is exportable to orbx.
Here is a sample with several lights and a background image.
You can remove the current AOV output, and try the different options to re-create it.