Pied Heron (Patreon)

Alpha One + FE 100-400mm F4.5-5.6 GM OSS

Capture Settings: 1250/second at f/5.6, ISO 12800

This image highlights what happens in low ambient light when shooting action with Aperture Priority and ISO Auto Min SS instead of Shutter Priority.

I captured this Pied Heron  a couple of days ago using my Action settings (Number 2 on the Shoot Mode dial) with Bird Eye AF selected from the Fn Menu. The ISO Auto Min SS is set to 1/2000 second and the ISO has reached its maximum 12,800 ISO value due to the low ambient light. If the aperture is at its maximum and the ISO can go no higher, the shutter speed may not be able to hit the 1/2000 second registered with ISO Auto Min SS without underexposing the scene.

Unlike Shutter Priority, Aperture Priority with ISO Auto Min SS prioritises exposure exposure over shutter speed, so if the shutter speed cannot be reached without compromising exposure, the nearest shutter speed to 1/2000 is used.

When this happens you have to either increase the Auto ISO maximum value or expect some movement blur. There is no right or wrong here just decisions that need to be made.

Note > The image has been processed in Lightroom and then Topaz DeNoise AI