The short answer
Check in this order. Is the light part of your image truly white, or is it a very light grey that the laser still marks? Do the mid tones still separate, or has the face become one flat area? Is the dot pattern fine enough to merge on this material? Is the power higher than the material needs? The first three are image preparation and cost nothing to test; only the fourth needs a new test piece.
Truly white, or light grey that still burns?
Do the mid tones still separate?
Does the dot pattern merge on this material?
Is the power higher than needed?
The most common cause: near-white that still burns
Camera images, scans and exported files rarely contain pure white. A background at 96 percent brightness looks white on screen, but a dither pattern still places a small share of dots there — and across a large area that reads as an even grey haze. We measured this on our own engine in September 2026: an image area at brightness 248 out of 255 produced roughly 2.6 percent burned dots, at 242 roughly 4.9 percent, and a tonal curve that pulled pure white down to 212 produced 10 to 14 percent — enough to veil an entire background. It is the single most common reason an engraving looks dull without any obvious defect, and the fix is in preparation: areas that should remain untouched material must be forced to true white before the dot pattern is applied.
Screen white is often 240-250, not 255
Measured: brightness 248 gave ~2.6% dots, 242 gave ~4.9%
A few percent of dots across a large area reads as haze
Fix it before the dot pattern, not after
The other three, and how to tell them apart
If the light areas are clean but faces look flat, the mid tones are over-compressed: the preparation has pushed too much of the range into one band. If the picture looks dark and closed rather than flat, the dots are probably merging — use a coarser pattern before you reduce power, because reducing power on a merged pattern usually just makes everything weaker. And if edges look swollen and the material is discoloured around the engraving, the power is too high for that material regardless of the image.
Flat faces: mid tones compressed
Dark and closed: dots merging, use a coarser pattern
Swollen edges and discolouration: too much power
How Vextrify helps
Vextrify treats white as untouched material: areas that are white in your source image are not engraved at all, so they cannot collect the faint dot pattern that causes the grey veil. The tonal work happens per material with goals such as a softer photographic look or a deeper, harder marking, and you see the prepared image at engraving size before committing a workpiece. If the result still needs adjusting, the recipe keeps what worked. The browser version is free and needs no account.
White in the source stays untouched material
Per-material goals instead of generic filters
Preview at engraving size before you burn