Convert Phots to Picolux

Convert Phots (ph) to Picolux (plx) instantly and accurately.

Phots (ph)
Picolux (plx)

Conversion Formula

plx = ph × 1.000000000e+16

About Phots

The phot (ph) equals 1 lm/cm² = 10 000 lx. The CGS-photometric unit of illuminance. Pre-SI optics texts express daylight in phots: full tropical sunshine is ~10 ph (100 klx); overcast sky ~0.1-0.2 ph. Wholly superseded by lux and kilolux in modern standards. 1 ph = 10⁴ lx.

About Picolux

The picolux (plx) equals 10⁻¹² lx. A theoretical subunit used only in precision photometric standard traceability. Even the faintest measurable natural illuminance - starlight on a moonless night at ~200 nlx - is 200 billion times brighter. Appears only in SI reference chains for calibration laboratories. 1 plx = 10⁻¹² lx.

Quick Reference Table

Phots (ph)Picolux (plx)
1 ph1 × 1016 plx
2 ph2 × 1016 plx
5 ph5 × 1016 plx
10 ph1 × 1017 plx
25 ph2.5 × 1017 plx
50 ph5 × 1017 plx
100 ph1 × 1018 plx

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