# Boring Thickness Parameters

> [!note] Esta página ainda não foi traduzida e é apresentada em inglês.


The Boring Thickness module exposes three measurement parameters in the right-hand properties panel. They control how Appearance Elements interprets the imaged crater and converts pixel radii into layer thicknesses in micrometers. Presets can also be created and saved.

![](../_images/20260611094523-TBD-Measure-Params.png)

### Drill Angle

The cone angle of the Säberg drill bit used to prepare the sample, in degrees.

- **Default:** 5.7°
- **Allowed range:** 0° – 90°
- **Typical values:** 5.7°, 8.5°, 14°, 26.6°, 45° (depending on the bit physically used)

> [!warning] The Drill Angle is the single most important parameter for accuracy. The calculated layer thicknesses are directly proportional to `tan(Drill Angle)`. Entering the wrong angle does **not** produce a warning — the module will return plausible but incorrect µm values. Always verify the engraved angle on the drill bit before measuring.

#### When to Adjust

Whenever the drill bit physically used to prepare the crater is replaced with a different angle. The default of 5.7° matches the most common Säberg bit but is not universal.

See also: [Drill Angle](glossary-of-measurement-parameters-drill-angle.md) in the glossary.

### Marker Color

A toggle that inverts the captured image before ring detection runs.

- **Options:** Dark or Light

The setting determines where the Auto mode finds the outer edge of the formed crater.

### Center Mode

A toggle that forces all rings to share a single common centre point.

- **Options:** Free or Locked (per-user preference; the last setting is restored when AE is launched).
- **Effect when Locked:**
    - Any new ring you draw inherits the centre of the **first** ring in the list.
    - When you drag the centre node of any ring, **all** rings move together as a group.
    - When you set to Locked with rings already present, all existing rings are immediately recentred onto the centre of ring #1.

#### When to Use

Set Center Mode to Locked for any **correctly drilled** Säberg crater — by geometry the rings are truly concentric, and locking the centre prevents subpixel detection noise from producing slightly offset circles, improving the consistency of layer radii.

Use Free Center Mode only when the crater itself is visibly asymmetric (for example, the drill was held at a slight angle) and you need to follow the actual ring positions rather than enforce a perfect cone.

### Presets

The default preset uses the 5.7° Drill Angle and the Dark Marker Color, default presets are not editable. To create presets:
- Press the plus button to open the Preset Creation Wizard
- Enter a name for your preset and press OK

![](../_images/20260611105342-TBD-Preset-name.png)

- Enter a description if required, this can be left blank
- The parameters are now editable, set the desired parameters and Press the save button to save the changes
- Presets can be deleted by opening a preset using the drop down and pressing the delete icon