Continuous shooting speed is usually measured as the number of frames captured in a short burst before the camera’s buffer fills. After the buffer is full, the rate typically drops and becomes limited largely by memory card write speed.

There isn’t one universal test standard, so results can vary by manufacturer or reviewer. In general, to measure maximum fps fairly, testers use settings that avoid slowing the camera down:

• a fast shutter speed, so exposure time doesn’t become the bottleneck
• good light and moderate ISO
• processing features turned off where possible (noise reduction, lens corrections, lighting optimization, etc.)

A shutter speed much faster than the frame interval is preferred. Practical examples mentioned were around 1/500s or faster; using very fast speeds helps keep shutter time from reducing the measured fps.

Scene content can matter a little because file size and in-camera processing may vary, so testers try to use conditions that are repeatable and not unusually easy for the camera.

So, quoted max fps generally means the best-case burst rate for a limited number of frames, not the sustained rate over a long sequence.