Tiled Deferred lighting producing different results from Standard Deferred lighting

Development Rendering
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I am seeing a difference in lighting results between the Tiled Deferred Lighting path and the Standard Deferred path

The following RenderDoc images are from the DirectLighting events of two consecutive captures. The only difference is forcing the Tiled Deferred path in one (and capturing), and then forcing the Standard Deferred path in the other (and capturing again)

Tiled Deferred Lighting

292808-deferred-tiled-lighting.png
292808-deferred-tiled-lighting.png1279×382 72.6 KB

Standard Deferred Lighting

292809-standard-deferred-lighting.png
292809-standard-deferred-lighting.png1290×381 69 KB

There are two spotlights in the image

  1. Red spotlight: 255, 0, 90 and 75000.0 cd

  2. Blue spotlight: 0, 0, 255 and 20000.0 cd

The output from the Standard Deferred path is ~5-5.5x brighter in red and blue (when pixel sampling in RenderDoc)

The issue is that we have surrounding particle effects that spawn “Simple Lights”. The light count often fluctuates above and below 80 (GNumLightsBeforeUsingTiledDeferred), which causes the renderer to toggle between Tiled and Standard lighting. This leads to significant flicker/changes in values as the renderer uses the different paths

Is there a known difference in shading between the two paths? Is there a suggested range of lighting values for the two paths? Has anyone else experienced this?

Thanks