Video scopes: Waveform / Vectorscope
Watch as an animation →Show brightness and color as graphs, so you set exposure and color without being fooled by your eyes or your monitor. The waveform shows the brightness distribution, and the vectorscope shows hue and saturation.
Before and after color grading, shot color matching, and applying a LUT, or when brightness looks different on a phone and a PC.
Exposure and color differ from cut to cut, so matching by eye alone quickly gets confusing. Look at the height of the darkest and brightest points on the reference cut's waveform and the shape of its vectorscope, and match the other cuts to that. When a person is in the frame, check that skin tones gather near the vectorscope's skin tone line (between red and yellow, at about the 11 o'clock position). To check a single frame with ffmpeg, use ffmpeg -ss 1 -i cut.mp4 -frames:v 1 -vf "split[a][b];[a]waveform=display=parade:scale=ire,scale=640:360[w];[b]vectorscope=mode=color2:graticule=green,scale=360:360[v];[w][v]hstack" scope.png. In Resolve, turn on the Scopes window on the Color page.
Check exposure and color on one frame by drawing its waveform and vectorscope side by side before you grade: ffmpeg -ss 1 -i clip.mp4 -frames:v 1 -vf 'split[a][b];[a]waveform=display=parade:scale=ire,scale=640:360[w];[b]vectorscope=mode=color2:graticule=green,scale=360:360[v];[w][v]hstack' scope.png. Match every cut to your reference frame and keep skin tones near the skin line.
Not verified