Rule Of Five Hundred: 7. The

Shutter Speed (seconds)=500Focal Length of the LensShutter Speed (seconds) equals the fraction with numerator 500 and denominator Focal Length of the Lens end-fraction

It identifies the threshold where the movement of stars across the sky begins to blur into streaks rather than appearing as distinct dots in a long-exposure image. 2. Application and Adjustments 7. The Rule of Five Hundred

The Rule of 500 is a formula used by photographers to calculate the (shutter speed) for capturing sharp, pinpoint stars without visible "star trails" caused by the Earth's rotation. The Formula: 7. The Rule of Five Hundred