Choosing grid width and color limits

Change one decision at a time

Grid width controls how much spatial detail the picture can hold. The color limit controls how many materials a conversion may use. Neither is a quality score. Compare the same source at 50, 100 and 150 cells wide, using limits of 8, 16 and 24 colors.

Inspect a conversion50 × 50 grid · 8-color limit · 6 actual colors50 × 50 grid · 16-color limit · 9 actual colors50 × 50 grid · 24-color limit · 13 actual colors100 × 100 grid · 8-color limit · 6 actual colors100 × 100 grid · 16-color limit · 9 actual colors100 × 100 grid · 24-color limit · 12 actual colors150 × 150 grid · 8-color limit · 4 actual colors150 × 150 grid · 16-color limit · 8 actual colors150 × 150 grid · 24-color limit · 11 actual colors

5,226 filled cells · 520 isolated cells · 616 cells in small regions

All conversions of the same source at 14 count

Grid	Color limit	Actual colors	Filled cells	Isolated	Small-region cells
50 × 50	8	6	1,304	129	189
50 × 50	16	9	1,304	279	375
50 × 50	24	13	1,304	301	401
100 × 100	8	6	5,226	368	444
100 × 100	16	9	5,226	520	616
100 × 100	24	12	5,226	572	658
150 × 150	8	4	11,747	321	439
150 × 150	16	8	11,747	761	925
150 × 150	24	11	11,747	837	953

PNG PDF JSON project

These are actual digital conversions using the same demonstration palette. A color limit is a maximum, not a promised number of colors. Different settings can produce identical results. Small-region cells belong to same-color groups of one or two cells connected horizontally or vertically. These counts describe the grid; they are not a difficulty score.

Read the picture as well as the numbers

Start at 100 cells and a 16-color limit in the comparison. Keep the width fixed and compare 8 with 24. Look at the eye, face boundary and larger color areas. Then hold the color limit fixed and change the width. More cells can preserve a contour while also increasing the amount of work represented by the grid.

Actual colors may be fewer than the limit. Isolated cells are single-cell regions; small-region counts include cells in small connected areas. An eye highlight can be intentionally isolated. Inspect these locations before treating a smaller count as an improvement.

Choose a usable starting point

Select the scheme whose important details remain readable to you. Use a few deliberate edits for a distracting cell or a broken outline. If the whole subject is hard to recognize, revisit the crop or grid size first.

Working with one bead board? See the fixed 29 × 29 comparison.