Lux vs estimated days
Contribution (life-ext / drain)
Front AMOLED solar
Rear glass-ceramic
Lux bands
Trek rear charge
| Name | Days | Panel | Lux | Hours |
|---|
Save two itineraries to compare, or read Current dial vs Amazfit lab ref.
Field guide
How dual solar works on this watch
The Amazfit T-Rex Dual Solar puts a solar layer on the front AMOLED (charges while you wear it in daylight) and a larger rear glass-ceramic solar plate that only sees sky when the watch is off-wrist — on a pack lid, rock, or dashboard.
Amazfit’s published matrix (typical use, no solar): 25 days. Add 3 hours/day at 50,000 lux on the front → 34 days. Same light on the rear → 51 days. Heavy use without solar sits at 13 days. Accuracy GPS is rated around 41 hours (47 with continuous front 50k lux per claims).
DualLux turns those anchors into a transparent scale: your hours and lux relative to the 3h @ 50k reference, weighted by front / rear / mixed panel mode, then GPS and AOD loads.
Lux reality check
Fifty thousand lux is bright clear sun — not an office window. Overcast often lives between about 1,000 and 5,000 lux; open shade around 10k; clear noon sun 50k–100k+. We ship approximate educational bands (IES / NOAA-style order-of-magnitude ranges), not calibrated meter readings. Treat the chart as planning physics for a watch, not weather science.
When rear charging helps
On multi-day treks with long GPS tracks, park the watch face-down in clear sun at lunch. The rear plate’s larger collection area is why Amazfit’s rear scenario nearly doubles typical life at the same 3h @ 50k reference. Desk weeks with half an hour of grey commute light barely move the needle — plan cable access.
Location lux proxies
Tap a city to load a clear-sky noon lux proxy (equinox-adjacent launch window). Seasonal cloud still wins — switch to an overcast band when the sky is socked in.
Glossary
- AOD
- Always-on display. Keeps pixels lit; DualLux default assumption is +15% drain (editable).
- Accuracy GPS
- High-precision tracking mode. Amazfit cites ~41 hours; DualLux maps your weekly GPS hours against that budget.
- Panel mode · mixed
- Split credit between on-wrist front hours and off-wrist rear hours (default 50/50).
- Life extension
- At Amazfit’s reference, front adds ~36% life vs typical; rear adds ~104%. We scale that by your hours and lux.