The formula to convert T-Stop to F-Stop is:
\[ \text{F-Stop} = \text{T-Stop} \times \sqrt{\frac{\text{Transmission}}{100}} \]
Where:
Let's say the T-Stop value is 2.8 and the transmission is 90%. Using the formula:
\[ \text{F-Stop} = 2.8 \times \sqrt{\frac{90}{100}} \]
We get:
\[ \text{F-Stop} = 2.8 \times \sqrt{0.9} \approx 2.66 \]
So, the F-Stop value is approximately 2.66.
T-Stop, or Transmission Stop, is a measurement that indicates the actual amount of light that passes through a lens and reaches the camera sensor or film. Unlike F-Stop, which is a theoretical value based on the lens aperture size, T-Stop takes into account the light loss due to the lens glass and coatings. T-Stop provides a more accurate exposure measurement, which is especially useful in cinematography where consistent exposure is crucial across different lenses.