Distributing controls

Putting all controls in one column makes plate effects (edge evaporation, temperature or dispense gradients) look like biology. Distribute controls spreads them so every row and column gets a balanced share.

Option	Meaning
Field	Category field to write to (default: Control)
Controls	Each control value and how many wells it needs. ＋ add control for more
Place in	Empty, non-edge (recommended), Any empty, or the current Selection
Pattern	Balanced spread: even across rows/columns and far apart. Random: random placement with a seed
Seed	Same seed → same placement. 🎲 picks a new one

4 Positive, 4 Negative and 8 DMSO controls spread over the empty wells (badges in the well corners). The placed wells stay selected, so you can give them a compound or concentration right away.

How the balanced spread works

Controls are placed one at a time, alternating between control types. Each goes in the candidate well that:

1. sits in the row and column with the fewest controls so far, then
2. is farthest from controls of the same type, then
3. is farthest from any control.

The result is close to a Latin-square layout, which is what plate-normalization methods (per-plate z-scores, B-score, pycytominer normalize) work best with.

Tip

If there aren't enough candidate wells, the dialog tells you how many it needs. Free some wells or choose Any empty.