Almost every disappointing terrain print comes down to one number, and almost nobody sets it deliberately. Here is the whole thing in about four hundred words.
The sum
Everything else follows from it. Note what is not in there: altitude above sea level. A mountain 8,000 m high in a frame where the lowest point is 7,500 m gives you 500 m of range, and that is all the printer ever sees.
Three worked cases
All at 150 mm print width.
| Place | Width | Range | At 1× | Use |
|---|---|---|---|---|
| Everest | 8 km | 3,238 m | 60.7 mm | 1× |
| Lake District fell | 6 km | 700 m | 17.5 mm | 1.5× |
| Norfolk Broads | 10 km | 25 m | 0.4 mm | 15× |
Everest needs nothing. The fell is fine as it is but gains a little from a nudge. The Broads are invisible without serious help.
Rules of thumb
- Range over 1,500 m: use 1×. Real mountains are already dramatic. Exaggerating them makes spiky nonsense that prints badly, shows layer banding on every face, and looks fake to anyone who has seen the place.
- 100 to 1,500 m: 1.5× to 3×. Hills, coastlines, river valleys.
- Under 100 m: 5× to 20×. Lowlands, deltas, cities, anywhere flat. This is not cheating; it is what every physical relief globe ever made has done.
The mistake that is not about exaggeration
When a mountain prints flat, the instinct is to raise the exaggeration. Usually the real problem is the frame being too wide.
Measured on the same summit at the same print width and 1×: a 4 km box around Everest stands 90.4 mm tall, and a 20 km box stands 36.2 mm — despite containing almost twice the vertical range. Widening the frame adds relief in metres and removes it in millimetres, because the scale shrinks faster than the range grows.
So before reaching for the slider, try halving the area. You will nearly always prefer the result. The Everest numbers in full are here.
What too much looks like
Three tells, in order of how quickly people notice:
- Slopes go past about 60 degrees and start showing hard layer banding, because every layer steps sideways by a visible amount.
- Valleys turn into slots too narrow for a nozzle, so they print as solid filled ridges.
- It stops looking like the place. This is the real one. Terrain has a shape people recognise even if they cannot name it.
Just let it choose
In the map maker, "Choose a good height for me" reads the height range of whatever you have framed and picks a figure, then tells you what it picked. On Everest it lands on 1×. On flat ground it climbs on its own.
Start there, then nudge by eye. The formula gives you the ballpark; your eye tells you when it is right.