How to Use the Dolby Vision Trim Controls | DaVinci Resolve
Aug 24, 2023
How to Use the Dolby Vision Trim Controls | DaVinci Resolve
Get an overview of how to use the Dolby Vision Trim controls to artistically adjust the mapping to home and cinema targets.https://professionalsupport.dolby.com …https://professionalsupport.dolby.com …https://learning.dolby.com https://prostore.dolby.com/collection …https://prostore.dolby.com/collection …http://bit.ly/Subscribe_Dolby https://www.dolby.com https://www.facebook.com/Dolby/ https://twitter.com/Dolby https://www.instagram.com/dolbylabs/ https://www.linkedin.com/company/dolb …https://www.tiktok.com/@dolby
Content
6.3 -> In this video, we're going to demonstrate
how to use the Dolby Vision trim controls
10.23 -> in DaVinci Resolve Studio.
13.02 -> These trim controls are a set of
modifiers that lets you adjust
16.26 -> and refine the mapping to other HDR
targets, as well as an SDR target.
21.345 -> To unlock the trim controls,
you need a license from Dolby.
25.784 -> If you have a Dolby Vision trim
license loaded, you will notice
28.825 -> that additional trim controls become active
as soon as you perform the analysis.
34.17 -> Once the Dolby Vision analysis is done,
it is highly recommended that you check
38.22 -> the mapping beginning with the SDR target.
42.54 -> Start trimming the SDR mapped version
by selecting the "100-nit BT.709, BT.1886" target
49.14 -> from the "Target Display Output"
dropdown inside the Dolby Vision tab.
54.855 -> Make sure to select "100-nit
BT.709, BT.1886, FULL"
59.68 -> for both the "Target Display Output"
and the "Trim Controls For".
66.12 -> Ensure that your reference
display and scopes are set
68.61 -> to match these SDR settings as well.
72.75 -> The Dolby Vision trim controls in version 4
offer both primary and secondary
76.86 -> controls to adjust the mapping for
the selected target display output.
82.259 -> Dolby Vision version 4 allows
you to offset the initial analysis
85.875 -> using the "Mid Tone Offset" control.
89.43 -> This control is useful
for matching the overall exposure
92.28 -> of the mapped image to the HDR master.
95.37 -> It acts as an offset to the L1
mid values and adjusts the mid tones
98.94 -> of the image without affecting
the blacks and highlights.
102.24 -> It is important to note that this offset
is applied globally to the shot
105.78 -> and will affect the mapping
at all targets for the shot.
108.87 -> The mid tone offset is recorded
as Level 3 metadata.
113.22 -> It is recommended to first
trim the mapped output
115.58 -> with the "Mid Tone Offset" control,
and obtain a better starting point,
119.03 -> before adding additional
primary and secondary trims.
123.78 -> Let's now move over to the primary
trim controls and have a look
126.72 -> at the various trim options.
128.88 -> Do remember that the primary and secondary
trims apply only to a selected target,
133.079 -> unlike the global "Mid Tone Offset".
"Lift", "Gamma" and "Gain" are designed
138.1 -> to work like traditional lift, gamma,
and gain controls in the color corrector.
143.22 -> Due to the current implementation
of signal transmission over HDMI,
147.1 -> the Dolby Vision mapping on
some devices is not constrained
149.96 -> to the active image area, but instead
is applied to the entire image.
154.08 -> This can cause the letter box
or blanking area to have elevated
157.23 -> black levels during playback.
159.4 -> Consequently, avoid using positive lift
values over 0.025 on letterbox content.
167.685 -> Higher values can cause the letter
boxed area to have elevated black
171.075 -> levels during playback lift.
174.045 -> Values below 0.025 do
not cause this effect.
179.835 -> If the image aspect ratio
matches the canvas aspect ratio,
183.405 -> so there is no letter box,
184.815 -> positive lift can be
used without constraints.
189.795 -> "Saturation Gain" adjusts the
overall saturation of the mapped image.
194.37 -> "Chroma Weight" trim helps preserve
color saturation in the upper mid-tones
198.5 -> and highlight areas, especially
when mapping down from HDR to SDR.
203.34 -> "Tone Detail" trim restores
sharpness only in the highlight
206.13 -> areas of the mapped image.
208.65 -> "Mid Contrast Bias" compresses and stretches
the image around the mid tone region
212.67 -> and can increase or decrease contrast
in the mid tones of the mapped image.
217.47 -> The "Highlight Clipping" trim reduces
or limits details in the highlights
220.859 -> by clipping them as required.
224.46 -> The secondary 6-Vector saturation
and hue controls allow colorists
228.299 -> to adjust the saturation and the hue
of the mapped image individually.
232.68 -> These controls are especially useful
when trying to fit or shift
235.68 -> the wide color gamut
of P3 or Rec. 2020
238.26 -> into the limited color gamut
of Rec. 709 SDR.
242.685 -> Both primary and secondary trim
values are stored as Level 8
245.895 -> metadata in Dolby Vision version 4.0.
250.155 -> You may choose to create trims
for SDR only, but you could also
253.695 -> add additional trims for other
targets like 600 nits HDR.
259.065 -> However, as the trims interpolate across
all targets, it's advised to start
262.995 -> trimming the 100 nit SDR version first,
and then continue with other targets.
268.425 -> Trims made at 100 nit SDR
also affect higher luminance targets.
274.78 -> The Dolby Vision trim controls
offer you a creative option
277.745 -> that can be applied on
as many shots as needed.
280.844 -> Use the option menu in the Dolby Vision
palette to copy and paste trim metadata.
288.81 -> Resolve also lets you copy
and paste analysis metadata.
292.74 -> However, analysis metadata should be
calculated individually for each shot
297 -> and copied from one shot to another
only for very specific use cases.
301.59 -> In addition to adjusting the trim
controls via the user interface,
305.01 -> you can also use Resolve's
advanced control panel,
307.53 -> as well as third-party MIDI
controllers to modify the trims.
311.525 -> Once you have finished your
trims, review the mapped output.
319.29 -> If you have other targets,
select a new target display output
322.27 -> and the corresponding trim controls,
324.32 -> and review the mapped output
for each target and trim as needed.
Source: https://www.youtube.com/watch?v=AVZ7xcgeEAM
