Macro lens slow focus

I’ve been testing the Sigma 105 f2.8 and Sony 90 f2.8 with my Sony A7iv and find that both lenses have a hard time to focus when shooting at f14 - f22.

It usually in day light with a focus light from my snoot or video light but the camera still struggles.

any tips on how to improve auto focus with smaller apertures?

In general, Sony mirrorless cameras focus with the aperture wide open in AF-S mode and stopped down to the shooting aperture in AF-C mode. In your case, it could be that the camera is trying to focus with the aperture stopped down and struggling due to the reduced amount of light reaching the sensor at f/14-f/22. If so, here are a couple settings you can try:

1. Set "Aperture Drive in AF" to "Focus Priority". This should make the camera focus with the aperture wide open even in AF-C mode.

2. If that doesn't work, try using AF-S instead of AF-C.

Thanks, I’ll try it out.

Wow the difference is night and day. AF is quick and locks on with little to no hunting all the way up to f22.

Thank you for the tip, I’ll give it try underwater over the weekend.

No problem, glad it seems to have helped!