The Curve module is the heart of the calibration workflow. You load an image, the app reads it, proposes a correction strategy adapted to its intent, and lets you adjust three simple parameters — black point, white point, midtone gamma. The result is a correction curve that you export to the standard

.acv

format of Adobe Photoshop to apply it in your usual printing workflow.

The approach is deliberately simple. No curve to draw freehand with a mouse, no complex interface to learn. Three sliders that cover 95% of cases, plus a continuous visual reading of what your correction does to the image — the histogram, the resulting curve, the corrected preview, updated in real time.

#What you'll find here

Eight pages covering the full cycle of a calibration, from reading to export:

Tonal analysis — the first step. The app reads the tonal distribution in L* CIELAB luminance, displays the histogram, and the Smart Analyzer proposes a correction strategy adapted to the mood of the image.
Understanding the curve — learning to read the correction graph: axes, typical shapes, twenty-five reference points that help reading without acting as parameters.
Manual adjustment — three sliders and a reset button. The whole correction fits in these four controls, updated in real time.
The 25-point curve — what's under the hood: a table of 256 values built by linear interpolation between the thresholds you set, smoothed to avoid angular breaks. The 25 points visible on screen are reading landmarks, not editable parameters.
ACV export for Photoshop — the standard
```
.acv
```
format, read natively by Photoshop. Loads in two clicks into the Curves palette, as a non-destructive adjustment layer.
Lightroom and other tools — Lightroom does not read
```
.acv
```
directly. Three workarounds depending on your workflow.
Presets library — saving a finished calibration to reuse later, without redoing the measurement.
Multi-zone correction — applying a different curve per region of the print (2 or 4 zones). For UV sources that don't light the surface evenly, and for large formats.

#Getting started

You've just imported a target or an image. Start with Tonal analysis — the first step of the module. Five minutes of reading to understand what you see on screen before touching the sliders.

You want to understand how the app computes the correction. Read The 25-point curve. It's not essential for using the module, but it's useful for interpreting the graph.

You've already finished a calibration and you want to apply it in Photoshop. Go straight to ACV export for Photoshop. Five minutes for the full procedure.

You work in Lightroom and you don't have Photoshop. Lightroom and other tools documents the three possible workarounds, with their limits.

You calibrate regularly and you want to save time. Presets library — saving a calibration to reapply it the following month without redoing the work.