Unknown. Help us by suggesting a value. (Canon EF 70-300 F4-5.6 IS II USM)
Unknown. Help us by suggesting a value. (Canon EF 75-300mm F/4-5.6 III)
The transmission result from the DxOMark set of metrics. Transmission refers to the amount of light that reaches the sensor through all of the glass elements of a lens, with a lower TStop signifying more light. This is important as less light reaching the sensor can lead to the requirement of higher ISOs or slower shutter speeds.
Transmission: is this important to you?