Lens adapter on camera: Can I change my aperture?

Many photographers wonder whether they can still change the aperture setting with a lens adapter added to their camera.

Aperture affects how much light enters a camera. Adjusting the aperture setting is a prominent part of photography; it allows a photographer to influence light exposure, and change the depth of field of the lens, thus altering the perception of objects in the foreground or background. Lens adapters allow you to mix and match different lenses with your camera. A camera that allows for different lenses gives a photographer more flexibility over focal length and aperture settings.

If you use a modern camera with autofocus functioning, a lens adapter doesn’t allow electronic data to transfer from the lens to the camera. This means autofocus features will no longer work. This also means that the aperture control won’t work properly. Essentially, the aperture would remain totally open, with no possibility to adjust it.

The only way around this is to adjust the aperture manually, using stopped down metering. To do this, open the aperture as wide as possible, while focusing on your subject. Then calculate the correct exposure for the ISO setting you intend to use. Next, set the shutter speed, and then stop the lens down to the required aperture setting. At this point, take the exposure measurement, if metering is supported on your camera. You can then shoot your photo. Look at your image and check the exposure. If it isn’t correct, tweak the aperture and shutter speed, re-take the photo and check again until your photo is spot-on.

Some lens adapters support electronic communication between the lens and camera, enabling the retention of autofocusing. Some lens adapters also allow you to use aperture-priority AE mode. However, you may still find there’s no automatic stop down and the aperture isn’t displayed in the viewfinder. There are also some lens adapters that let you control aperture by a panel on the adapter, rather than the camera itself.

The newer generation of lens adapters with power functioning aren’t cheap. If you are thinking about getting one, weigh up whether it’s worth paying the extra cost.