Configuration

Everything an operator tunes lives in the measurement config (config/*.yaml, frozen into the plan — a resumed run refuses a changed configuration).

Per-experiment parameters

Key	Default	Adapt when
sample	"sample-000"	Always — recorded in every row record, and the first part of each frame’s name.
qds	one dot at (0, 0)	One entry per quantum dot to sweep: id, x_um, y_um (chip frame; recorded for the future positioning stage — the steps assume the dot is already localized). The id is the second part of each frame’s name.
hwp.start_deg / stop_deg / step_deg	0 / 90 / 2	The angle series, endpoints inclusive. The plate angle sets the excitation power: HWP 0–90° takes it through one full period; 0–180° covers two for symmetry checks. Finer step_deg = more rows.
spectrum.exposure_s	1.0	Per-row exposure in seconds, set by signal strength. A list such as [0.5, 1.0] takes one spectrum per exposure at every angle, in the order listed.
spectrum.frames	1	Frames stored per acquisition (the row is frame 0).
powermeter.wavelength_nm	780	The excitation laser’s wavelength, not the emission’s (powermeter correction curve).
powermeter.averaging	10	Samples per power reading (~3 ms each), taken inside the exposure window.
powermeter.delay_s	0.4	Delay before the power sample so it lands inside the exposure (LightField opens the shutter ~0.3–0.5 s after the call).
(whole powermeter block)	present	Delete it for a spectra-only sweep — no PM_ADDRESS, no powermeter server, no power keys in the records.
analysis.enabled	true	Analyse each dot’s power series after the sweep (needs the powermeter block): the integrated counts and every fitted line against the power, each with a power law $I \propto P^k$; results and report under the run’s analysis/.
analysis.region_nm	null	[start, stop] holding the dot’s lines — integrated, and where lines are fitted. Set it when the window also shows substrate or neighbouring dots.
analysis.background_nm	null	[start, stop] free of emission, for each frame’s background and noise; null takes the frame’s median.
analysis.snr	5.0	A point enters a power-law fit only this many noise σ above zero.
analysis.fit_options	{}	Passed to plesty.lib.analyzer.SpectrumFit over the defaults (prominence 40 counts, Gaussian lines, constant background, FWHM bounded to 0.03–0.3 nm), e.g. peaks: [787.7, 789.3].
step_settle_s	0.3	Pause after each completed row — breathing room for the instrument stacks.
max_retries / retry_sleep	2 / 3.0	Per-step retry policy for transient failures.

Spectra-only sweeps

Delete (or comment out) the powermeter block. The plan then contains rotate-and-expose rows only, the rig is built without the powermeter, and the records carry no power keys. A plan that promises power readings refuses to run on a rig without a powermeter rather than producing rows without the reference.

A worked example ships with the module: config/fullrotation-spectra.yaml, the configuration of the first successful spectra-only full rotation (2026-08-14) — run it as uv run python -m plesty.pow_pl --config config/fullrotation-spectra.yaml.

What is not per-experiment

The packaged plesty/pow_pl/config.yaml holds hardware constants — which sub-devices the rig is made of and their operation budgets (move/home timeouts, acquire grace). Those are properties of the instruments, and changing them belongs in a commit, not in a run config.