# Check a depth map before relief engraving

> Compare bit depth, usable grey levels and engraving passes, then adjust levels if needed.

A depth map uses pixel values to describe height. In this tool, black is deepest and white is the untouched surface. The inspector shows the values in the file and a relief preview; it does not calculate laser power, speed or the depth your material will actually reach.

## What you need

- A depth-map image, or one of the built-in samples. PNG, PGM and PPM preserve the stored values for exact inspection in this tool.

## 1. Open a sample or your depth map



Choose a sample first, or use **Choose a depth map**. You can also paste an image with Ctrl+V. The image is processed in your browser. Use a PNG, PGM or PPM when checking the original bit precision; JPEG, WebP and BMP are read through the browser at 8 bits per channel.

## 2. Read the report



Compare the reported bit depth with the distinct levels actually present. An 8-bit channel can hold up to 256 values; a 16-bit channel can hold up to 65,536. Saving an 8-bit image in a 16-bit file does not recover missing height detail. A simple design may legitimately use only a few levels.

## 3. Preview your engraving passes



Set **Passes** to the count you plan to use and turn on **Show the passes**. Compare the terraced preview with the smooth view. Change the exaggeration to inspect small steps, then check the report for passes that add shape versus passes that only deepen a flat recess.

The width and engraving depth set the preview dimensions. Confirm the image’s depth direction and job settings again in your laser software, and test on the intended material.

## 4. Adjust levels only when needed



If the map uses only part of the available range, open **Fix levels**. Choose the values that should become full depth and untouched surface, inspect the result and download the 16-bit greyscale PNG. Keep the original file. Stretching or clipping levels changes the relief and cannot recreate detail that was absent.

## Troubleshooting



What the preview or report is telling you

| What you see | What to check |
| --- | --- |
| A 16-bit file with only 256 levels | Compare it with the original export. A larger file format alone does not add more height detail. |
| Terraces in the pass preview | Compare the pass count and the distinct levels in the source. Raising the pass count cannot create missing source detail. |
| The entire surface is recessed | Check whether the lightest pixels reach white. Only expand the range if those pixels should represent untouched material. |

## Make it yours

Compare the Genuine 16-bit sample with the byte-copied 16-bit sample at the same pass count. Explain why a similar-looking image can produce a different set of height steps.

---

Open the Depth Map Inspector: https://www.mylasertools.com/depth-map-inspector
Read online: https://www.mylasertools.com/learn/guides/depth-map-inspector