CinePerfect — test charts
=========================

Eight charts, 3840x2160, 16-bit PNG, encoded in V-Log code values.
They let you verify what CinePerfect does, on your own scopes, without
taking anyone's word for it.


HOW TO USE THEM
---------------

1. Import the PNG into Final Cut Pro.
2. In the Info inspector, set Camera LUT to None.
3. Apply CinePerfect. Set the preset to None and Source format to
   Panasonic V-Log.
4. Set your library to Wide Gamut HDR. In a Rec.709 library Final Cut
   delivers 8-bit, and gradients will show banding that does not come
   from the plug-in.


IMPORTANT — these files are pre-compensated for Final Cut Pro
-------------------------------------------------------------

Final Cut guesses the gamma of still image files and applies
code^1.1236 to them. On an ordinary display-referred picture that is
negligible. On a log curve it is not: in V-Log one stop is only 0.0727
in code, so a four-point error is 0.55 EV.

These charts are pre-distorted by the inverse, so they read correctly
inside Final Cut. Used anywhere else — a scope fed directly, a
compositing app that respects the file — they will be off by the same
amount in the other direction.

Camera footage is unaffected: real clips carry an explicit tag, so
nothing is guessed and nothing is corrected.


WHAT EACH CHART SHOWS
---------------------

01-exposure-stops
    Eleven patches, exactly one stop apart around 18% grey, plus a 0.18
    reference band. With the None preset at 0 EV, the 0.18 band reads
    47% on the waveform. Push exposure +1 EV and every step lands
    exactly where its neighbour was: the waveform translates by one
    notch, whole, without deforming.

02-highlight-recovery
    A continuous ramp from 0.02 to 24 linear, and five blocks of fine
    structure buried at +2.5, +3.5, +4.5, +5.5 and +6.5 stops. At 0 EV
    the top blocks look flat. Pull exposure down and the detail comes
    back, sharp — the point being that exposure re-exposes the image
    rather than brightening it.

03-skin-latitude
    Six skin tones across seven exposures. Watch the hue, not the
    lightness: on each row it should stay constant. On a vectorscope
    the cluster moves in radius, not in angle.

04-film-density
    Six rows built to isolate what must move from what must not. The
    neutral row is a strict control: film density must not touch it.
    Measured, it does not move by one hundredth at any dose.

05-source-formats
    18% grey and 90% white encoded in all eleven log curves, side by
    side. Select one format in CinePerfect: only its patch should read
    47%. Note that F-Log2 and LogC3 encode 18% grey at the same code
    (0.3910) — that is a real coincidence of the two curves, not an
    error, and the 90% row separates them.

06-halation-bloom
    Bright sources on a dark field, for setting halation and bloom.

07-grain
    Flat fields at several densities, for judging grain without image
    detail interfering.

08-sharpness-olpf
    Fine detail including cells at the four corners, for the optical
    low-pass filter and lens softness. The corners matter: they show
    the effect follows the frame, not the render tiles.


https://cineperfect.app
