- Hold
- How long a mark survives once nothing is re-lighting it. Hard right and the exposure never closes.
- Catch
- How bright something has to be before it leaves a mark. Low paints with the whole frame, high with the highlights only.
- Drift
- Travel of the held paint. At zero the marks stay where they were made; above it they slide and stretch into streaks.
- Heading
- Which way that travel goes, all the way round the clock.
- Bleed
- How much the paint spreads each pass. Low is a hard filament, high blooms every streak into a soft smear.
- Shift
- Hue turn per pass on the held paint, so a streak changes colour along its length as it ages. Centre holds the colour it was made in.
- Glow
- Weight of the painting over the live picture.