MVLscope

TINY WORLD / A PERCEPTION PUZZLE

Bump or Pit?

A hill or a hole? Your first impression might change.

Surface 1 / 3
First impressionsSame shape. Different contrast.
SIMULATED
Move the detector

Watch the bright and dark sides swap. The surface does not move.

Which way does each go?

Bump = raised · Pit = sunken

Check your choices first, then inspect the known surface and its cross-sections.

No timer. Explore the shading before revealing the shapes.

Loading puzzle…

FROM CONTRAST TO SHAPE

Same surface. A different view.

Inspect feature

Known surface

Camera can turn

Model cross-section

The dashed line is the surrounding surface.

Known game geometry · dimensionless · not reconstructed from an SEM image.

Drag or use arrow keys to turn.

Fixed lighting makes the 3D shape visible. Moving the detector changes the paired contrast image, not this lighting.

SEM-inspired contrast

Top view stays fixed
Move the detector

Try the opposite detector. Which slope changes brightness? The bumps and pits keep the same heights.

Compare the model cross-section

The dashed line marks the surrounding surface.

A LITTLE SCIENCE

Brightness is a clue, not height

These invented surfaces use simplified SEM-inspired contrast. Moving the detector changes the bright and dark slopes. It never turns a bump into a pit.

Real SEM detectors collect electrons; they are not lamps. Real contrast also depends on the specimen and imaging conditions. A bright patch alone does not tell you its height.

After checking, you can rotate the same known surface in 3D and reveal its cross-section. Neither is reconstructed from the image. The 3D surface uses the same dimensionless heights and lateral coordinates, without vertical exaggeration. Its fixed lighting helps show shape; the detector marker is a collector, not a lamp. The surfaces have no physical scale. This is a perception puzzle, not an instrument simulation or a test of microscopy skill.

You can change your choices until you check them. Checking reveals every answer and ends that round. Each link recreates the same three surfaces. Answers are not saved, and there is no leaderboard.

Optional scientific references