Can You Use Manual Focus Lenses on Your Digital SLR with an Adapter?

Photography enthusiasts often wonder whether they can use a manual focus lens with a digital single-lens reflex (DSLR) camera. This decision heavily depends on the register distance, which is the distance from the lens mount to the sensor or film. Different camera brands have different register distances, and this can affect the compatibility of lenses.

Compatibility and Register Distance

A Canon EF camera body has a short register, making it more likely to adapt to a variety of manual focus lenses. Manual focus lenses for cameras like Canon, Nikon, and others can provide excellent photography opportunities, especially when combined with a suitable adapter. However, not all adapters work with all lenses, so it's important to research compatibility beforehand.

While DSLRs are still widely used, the trend is shifting towards mirrorless cameras. Mirrorless cameras lack the swinging mirror found in DSLRs, which makes them more adaptable to manual focus lenses from traditional SLR cameras. This versatility makes mirrorless cameras a popular choice for those who frequently use manual focus lenses.

The Challenges of Using Manual Focus Lenses

Using a manual focus lens on a DSLR requires a basic understanding of photography. Not only do you need to focus manually, but you also have to set the aperture and shutter speed for the correct exposure. For smooth settings, especially in low-light conditions, you can set the DSLR to manual or aperture priority mode.

To set the aperture, you need to adjust it to match the shutter speed, with a digital camera line graph displaying proper exposure when the pointer is at the center. Alternatively, a light meter can provide the correct exposure settings to apply to the manual lens.

Examples of Manual Focus Lenses

Several well-known brands offer manual focus lenses that can be used with a DSLR. Examples include:

These lenses require manual adjustments, and focusing can be more challenging than with autofocus lenses. Modern digital cameras lack the focusing screens that facilitated manual focusing in older SLRs, making the process more difficult. In a DSLR, the optical focus screen can be dark unless the lens is wide open, so you often need to focus with the lens wide open and then stop down to set the exposure.

Using Manual Focus Lenses on a Mirrorless Camera

Using a manual focus lens on a mirrorless camera is less challenging due to the absence of a swinging mirror. This makes mirrorless cameras more adaptable to manual focus lenses from traditional SLR cameras. I have used my late 1970s Nikon lenses on my current Nikon mirrorless camera. However, I need to set the camera to manual or aperture priority mode because there is no electronic linkage between the camera and lens. Focusing can be a little difficult, and it is more challenging with a DSLR due to the lack of an aperture linkage. Unless the lens is wide open, the optical focus screen is dark, so I have to focus wide open and then close down to set the exposure.

Another scenario where using a manual focus lens is beneficial is when photographing stars, where autofocus doesn’t work in low light conditions. Manual focus lenses are usually cheaper than autofocus lenses, making them a cost-effective option.