Author Topic: dolby vision improves challenging video footage  (Read 705 times)

70MM13

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dolby vision improves challenging video footage
« on: March 18, 2022, 05:12:06 PM »
timbytheriver came up with a method for hybrid HDR-REC709 processing with Dolby Vision, and it made a dramatic improvement to this example video I shot a few years ago on my 5d3 (3072*1308 14 bit)

I previously had serious difficulties with the more extreme dynamic range shots, particularly the closeup of the oscilloscope.  It formerly required trickery such as spot exposure reduction on the LED to get the right saturation without losing all the contrast in the rest of the shot.  Now it was straightforward and looks great with no trickery!

This workflow also revealed details that were previously absent, such as the sky through the (filthy) windows in dimly lit interior scenes.  Incredible colour!

On another note, I was so pleased with the new grade that I re-rendered the blender animations, and in the process I found that the "eevee" realtime raytracer is now very close to production ready, so I used it, and it was a real game changer.  What a treat to see lighting adjustments on the fly...


whysodifficult

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Re: dolby vision improves challenging video footage
« Reply #1 on: March 18, 2022, 11:58:01 PM »
Nice, how can we try it?

timbytheriver

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Re: dolby vision improves challenging video footage
« Reply #2 on: March 19, 2022, 11:58:07 AM »
The overview (in DaVinci Resolve) is to grade in HDR Rec.2020, ST.2084(PQ), Analyse using Dolby to produce an SDR 100nit version, and finally export as SDR Rec.709.

I've no idea precisely what's going on in the 'black-box' of Dolby, (and unless you have the annual ££$$ license from Dolby, you can't access the trim controls) but tests have shown that in shots containing extreme dynamic range (see the Android Pop video posted above) something good happens to the treatment of highlights versus simply just grading all the way along in SDR Rec.709.

Basic flow:

1) Set your Resolve project up as above, with mastering and scopes set to 1000nits
2) Grade in HDR – push your extreme highlights [only] up to the 1000nit mark, pay attention to saturation
3) Use the Dolby controls to 'Analyse clip(s)' at the selected SDR level from the drop-down e.g. SDR 1886 Rec.709 100nits
4) Check the results with the 'tone mapping preview' ON
5) If the Dolby Gods have willed it, there will be enhanced 'detail' and colour in the highlight roll-off
6) Export the clip in the Delivery tab as Rec.709/2.4 or Rec.709-A if on Apple device, and select the Dolby tone-mapping preview from the bottom of the Advanced controls.

Your mileage may vary…!

5D3 1.1.3
5D2 2.1.2

shankar101

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Re: dolby vision improves challenging video footage
« Reply #3 on: April 07, 2022, 07:46:54 AM »
quiet confusing . in which mode should i record in lantern ?