T-Stop to F-Stop Calculator

Convert T-Stop to F-Stop



Formula

The formula to convert T-Stop to F-Stop is:

\[ \text{F-Stop} = \text{T-Stop} \times \sqrt{\frac{\text{Transmission}}{100}} \]

Where:

Example

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.

What is T-Stop?

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.