Soft proofing

Preview a photograph in an export colour space and highlight colours that fall outside its range.

In Develop, click the proofing button beside focus peaking and the magnifying glass. Choose sRGB, Display P3, Adobe RGB or ProPhoto. With a space selected, use the warning switch or ⌘⇧Y to show out-of-gamut areas.

The preview converts to the output encoding, clips channels to 0–1 and converts back. The warning marks changes greater than 0.01, measured through the sRGB curve for each destination. Highlights above the output range are marked consistently with the clipping overlay.

Soft proofing affects the canvas only. It does not change histogram measurements, cached previews or Photos publishing. Changing photographs turns it off.

An original decode is required. The button is disabled over a proxy and its tooltip explains why.