"Process Background and Environmet Maps" not working?

[Anonymous]

I want to try render model with photo background using perspective match. 

My photo has correct exposure so I don't want scene lighting to affect background photo. To achieve this, I untick option "Process Background and Environmet Maps" in:

Rendering > Environment > Expossure Control rollup

When I click "Render Preview" in same location (next to the option itself) everything looks good. When "Process Background and Environment" is ticked background photo is affected by scene lighting and camera exposure settings. When the option is unticked background on preview is not processed and has default exposure.

However, when I render scene with Production or ActiveShade Mode the background image is affected by scene lighting and camera exposure regardless of whether the option is on or off.

I'm getting same behaviour with Arnold CPU/GPU and ART renderers.

Have I missed some important option or it is a bug?

To recreate this in new project:

1. Add bitmap to Material Editor. I tried to use 16bit TIFFs and 8bit JPGs - no difference:

2. Press "8" to open "Environment and Effects" option tab and drag bitmap output to "Environment Map" button and choose Instance Method:

3. After last step Mapping of our bitmap will change to Spherical Environment, so change it to Screen in order to use it as normal background photo:

4. Make Perspective view active by clicking in it and press Alt+B to open Viewport Configuration > Background tab. In there select "Use Environment Background" and then click "Apply to Active View" and then "OK":

5. Now back to Rendering > Environment... tab (press 8 for shortcut) and click "Render Preview" with "Process Background and Environment Maps" option ticked. Then untick the option and repeat with render preview. I get two different background exposure which I believe is correct behavior:

6. Finally click "Render production" with the option turned on and off and get no difference in background exposure - the background photo is always processed. Looks like the option is not working. 😕

Like I mentioned before it is no different if I setup camera/lighting and/or choose different renderer.

Any ideas what I'm doing wrong?

[irishman_team_kilber]

exposure control is only meant for the daylight system, https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2018/ENU/3DSMa...

[Anonymous]

I don't think that is the case. I was using it successfully without daylight system.

Anyone can at least confirm or deny same strange behaviour?

[irishman_team_kilber]

You can tell your image is over exposed when you turn on the exposure control, Create a daylight system Once your geometry has been properly imported for example into 3ds Max, you have to create a so-called “Daylight System” object. A Daylight System models the orientation and celestial hemisphere under which your scene geometry is placed (i.e. the intensity of the Sunlight and the Skylight).

https://www.architectsjournal.co.uk/journals/1/files/2009/2/22/3ds_max_design_2009_daylight_simulati...