How to color grade HLG footage from Sony Xperia Cinematography Pro

6 Dec

Sometimes I use my smartphone (currently a Sony Xperia 5 III) for shooting video, especially some B-roll clips. However, in the beginning, I found it difficult to achieve good colors and properly exposed video. Then I did some systematic tests and found out how to best use this great smartphone camera for shooting beautiful video.

In Cinema Pro I use the Style "--". So I shoot without any predefined color grading. The MP4 file I get by this method has color primaries BT.2020 with transfer characteristics HLG, chroma subsampling 4:2:0 with 10 bits depth.

Correct Exposure

I typically use the built-in Sony Photography Pro app in "P" mode with Spot-metering to determine the intended exposure. Therefore I point to an area I want to be equivalent to neutral grey and read shutter speed and ISO. If there is no neutral grey equivalent then I take surfaces like grass or sky and I know that these should be overexposed by 1 or 2 stops. The exposure determined that way I correct by -2/3 EV and transfer it to the Cinema Pro app. Important is to check the white balance. The exposure scale included in Cinema Pro I don't use at all.

Editing in Davinci Resolve

After importing into Davinci Resolve the Xperia HLG videos look faded with a slight color cast. The scopes should show good exposure without highlight clipping:

Davinci Resolve Scopes for the Xperia HLG Clip showing correct exposure straight out of camera.

Finally I apply one of my LUTs for initial color grading. The example below shows the original HLG footage compared to the graded image. In that case my Sony Xperia HLG_Standard LUT was used, which mimics the colors of a JPEG image shot in Creative Style "Standard" with my Sony Alpha A7R III.