7. The Rule Of Five Hundred [TOP]

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

Example: For a 24mm lens on a Nikon crop sensor (1.5x), the effective focal length is 36mm ( ). The rule would be 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