iccery-v2-mac/docs/07-stage0-calibration.md

07 — Stage 0: printer calibration (printcal / applycal) (#224)

Optional dashboard opened by Calibrate Printer (#btnCalibratePrinter). The 1–5 wizard is unchanged when skipped.

Why CAL_ prefix

Calibration charts use basename CAL_<run> so they never collide with profiling .ti1/.ti2/.ti3. printtarg -K file.cal is applied only to profiling layouts, never to the calibration chart itself.

Flow

1. Generate Calibration Target → targen via build_calibration_targen_args
2. Create Layout & Print → existing Stage 2 printtarg + native print (same unmanaged path)
3. Measure Chart → existing Stage 3 chartread
4. Compute Curves → printcal (captured, not streamed)
5. Toggle Apply Calibration → subsequent profiling printtarg -K and post-colprof applycal -a

targen for calibration wedges

-v -d {2|4} -s {steps} -g {steps} [-n {steps}] -e {white|4} [-l {tac}] -f 0 CAL_<basename>

• RGB: -d 2; CMYK: -d 4
• Steps clamped 11–51, default 21 (#calSteps)
• Neutral emphasis: -n same as steps
• CMYK ink-limit exploration: -l 200–400 (#calInkExplore, default 320)
• -f 0 — no full-spread patches (wedges only)
• Default 4 white patches if unspecified

printcal

-v -e [-I] [-z] [-a previous.cal] [-m TAC] [-xC pct]… -o out.cal CAL_basename

Flag	Meaning
-e	even (always passed)
-I	no ink limit
-z	verify
-a	previous .cal
-m	total ink limit
-xC / -xM / …	per-channel limit
-o	output .cal

.cal overwrite requires Overwrite / Rename / Cancel (#calCollisionDialog). Never silently clobber.

applycal (after Stage 4)

-v -a <cal> <input.icc> [output]

JS never sends -u (unapply). Fork -u on applycal is not JSON.

Staleness

Warn if loaded .cal is older than calibration_stale_days (default 30) or stored printer name differs. CMYK Stage 1 shows "No calibration applied" reminder.

UI

Channel-response SVG (#calCurveSvg): solid = post-linearization, dashed = identity. TAC card + per-channel limit editors. Recommended power shown for targen -p.