DJI Mavic 3 Cine – Exposing, Noise and Image quality

20. November 2021

The test tries to find out how to expose with the Mavic 3 Cine 4/3 camera and getting the best results in terms of image quality and noise. The lower 18% reflective grey card in the image is our reference as it catches softened 5600K fill light like we would have outside on a cloudy day. The camera settings are 5,1K ProRes D-LOG. All measurements are made in DLOG Mode.

We exposed in both ISO 400 and ISO 800 three times:

  • Middle Grey to 40 IRE, which meant a 1.3 under-exposure on the DJI MM indicator
  • Middle Grey to 50 IRE, which meant a correct +- 0 exposure on the DJI MM indicator
  • Middle Grey to 60 IRE, which meant a 1.3 over-exposure on the DJI MM indicator

After that we imported the footage to Davinci Resolve Studio 17, analyzed the material on a Flanders Scientific DM240 reference monitor and corrected the over and under exposed shots to match with the “correct” exposed ones. We used the official DJI “Mavic D-Log to Rec709” LUT.

Results.

Pushing the under exposed shots by 1.3 stops of course results in an increased amount of noise. Doing this with ISO 400 still leads to a usable image (without any Noise Reduction). The pushed ISO 800 on the other side results in an image which could not compare to any high sensitivity pictures we are used from modern cameras.

In terms of image quality it turns out that both push corrections (ISO 400 and ISO 800) will result in a notable red shift as well as in a loss of dynamic in the darks. The darks appear muddy and lose information.

Pulling the over exposed shots by 1.3 stops of course results in a decreased amount of noise.

The image looks super clean and pleasant. It may also be a matter of taste but we like the pulled version better in terms of noise.

Noting that our test setup is more a low light scene we could not determine too much loss of dynamic range in the highlights though the brightest part (lightbulb on the right) definitely clipped the signal and information got lost there. The DLOG curve may not be too forgivable here but some high key tests should figure out more in this term.

Disregarding under and over exposure our general impression about the two ISOs is:

ISO 400 definitely is the sweet spot of the sensor and if possible you should stick to this value especially as ISO 800 (even without pushing or pulling) also results in a notable red shift in the darks!!! The amount of noise may not be too pleasant but acceptable in situations where you just do not have enough light around. Be prepared of using a noise reduction afterwards.

Conclusion in short.

  • Try to not under expose
  • Expose by using a middle grey value of 50 IRE or use the MM indicator within the DJI Fly App (+-0.0)
  • Over exposing by around 1 stop is a chance to result in a pleasant and clean image but be careful of not clipping any highlights (as the DJI Fly histogram may not be displayed detailed enough to tell and the over exposure warning only affects in normal mode a second monitor with waveform option connected to the RC via HDMI could be an option to determine clipping)

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