Set the filter, aperture, ISO, shutter and bracket for each phase of totality. Each one is scored against NASA's published exposure guidance, the tables compiled by Fred Espenak, so you can see at a glance where you're dialed in and where you're a stop hot or cold. The corona is the hard part: it spans ten stops, so your bracket has to tile the whole range. This is the same planner built into Umbra.
The whole plan at a glance
NASA's guidance (the tables compiled by Fred Espenak) sets each feature's exposure from t = f² / (ISO · 2^Q), where Q is the feature's brightness. Q values are the NASA/Espenak table: Baily's beads Q12, chromosphere Q11, prominences Q9, the diamond ring (corona 0.2 Rs) Q5, and the corona from Q7 at 0.1 Rs down to Q-3 at 8 Rs. Partials follow your filter (ND 4.0 is Q11, ND 5.0 is Q8); the Thousand Oaks Optical option uses a field-measured Q5.2 baseline (about 3 stops brighter than a generic ND 5.0). Earthshine sits past the published table, so its target is a common earthlit-disc practice value, and the fastest beads exposure still reads a touch bright because Q12 wants a shutter faster than most cameras offer. Every shutter here is snapped to a real camera speed. Umbra can also read the exact values a universal-driver body offers (Tools ▸ Camera Profiler) and snap to those. Espenak's guide · NASA Table 23 · what's in Umbra.