Exposure & Metering
3 terms
T-stop
Exposure & Metering
T-stops
A measured aperture value that accounts for the light a lens actually transmits, rather than the geometric ratio an f-number implies.
T = N / √(transmittance)
Third Stop
Exposure & Metering
stops (EV)
A one-third-stop increment, the fine adjustment step most digital cameras use for aperture, shutter speed, ISO and exposure compensation.
⅓ stop = ×2^(1/3) ≈ ×1.26
Time Mode
Exposure & Metering
seconds
A shutter setting, marked T, that opens the shutter on one press of the release and closes it on a second.