Mirrorless Compact System Cameras (CSC) are great at a lot of things. They’re smaller, with smaller lenses, they have ultra-accurate autofocus and in most cases very high quality native lenses. However, one of the biggest advantages of these mirrorless cameras is the ability to mount and use almost any manual focus lens ever made.
All the major mirrorless camera systems, including Micro 4/3, Fuji X, Sony NEX, Samsung NX, Nikon 1 and Canon EOS M, feature a lens mount register distance that is very, very short in comparison to DSLRs and even most existing rangefinder systems, such as Leica M or Contax G. This allows one to mount lenses for any other system to the mirrorless camera using a simple mechanical adapter.
You can easily use lenses for Contax/Yashica, Leica M, Leica R, Canon FD, Minolta MD, Konica AR, Olympus OM, Nikon F, Canon EF (with some limitations), M42 Screwmount, Leica Thread Mount, Contarex, Alpa, and the list goes on and on. Instead of the limited number of lenses made specifically for your system, you can literally use thousands of different lenses from dozens of manufacturers.
This article takes a deeper look into the potential options available to you, how some of these lenses perform, and why, if you own a mirrorless CSC, you should definitely look into adapting some excellent older glass to your camera.
Why Should You Adapt?
If you’ve not used any manual focus lenses on your modern digital camera, you may be asking yourself why someone would want to shoot with one. There are lots of reasons, but let’s take a look at what are, in my opinion, the five biggest ones:
Gain capabilities not available with native lenses
While some mirrorless systems, like Micro 4/3, have very large lens lineups, all mirrorless systems have gaps in capability that the native lenses don’t cover. None of the CSCs have fast telephoto lenses in the 300mm range or longer. None of them have tilt/shift ability, and even when there are good options for say, a fast portrait lens, most of these systems don’t have multiple options.
Whether it’s adding a 300mm f/4 for a high-end telephoto lens or using a fast 50mm lens for some shallow depth of field, adapting quality manual focus lenses is often a good way of getting the lens you need without waiting for the camera manufacturer to release a new product.
While there are some truly excellent mirrorless lenses out there for all systems, in some cases, the native lens in the focal length you want may just not be up to snuff. In this case, there may be a truly excellent manual focus lens that has the optical quality you’re looking for. Sometimes you’ll end up paying through the nose for these lenses, such as is the case with adapting more modern Leica M lenses, but if you are after the best, in many cases you can get it.
You Can Save Money
While many manual focus lenses, even those 40-50 years old, can be quite expensive if they are top-tier optics, rare, or have the words ‘Leitz’ or ‘Zeiss’ written on them, there are tons of very high quality lenses out there that can be had for very little money. Fast 50mm lenses are a prime example. Most fast 50mm lenses from the 60s through the 80s are quite
good optically and can be had for a song. A good 50mm f/1.4 will often run you about $100, while an f/1.8 version may only cost you $30-$50 in excellent condition. The more specialized you get, the more the price will increase, but still, in many cases you can save money.
That Unique Look
When lenses are designed by the optical engineers at a company, there are design considerations and tradeoffs that are made. As a result, often lenses with the same specifications will have drastically different renderings of a scene. One lens may have been optimized for wide open sharpness, but as a result, the bokeh is wild and harsh. Others may have a soft dreamy glow, or produce super contrasty and saturated images, or produce crazy, swirly backgrounds, or be very low contrast and mild, others may be clean and clinical. What this allows is for you to choose the right lens to give you the look you want right out of the camera, which saves a lot of time in post processing. In many cases, the look you get with some lenses absolutely can’t be replicated in post. This is one of the key reasons to adapt, in my opinion: it gives you a tremendous amount of options to get the look you’re after.
Shooting with these lenses is a lot of fun…trying out new things, learning about old gear and perfecting your manual focus technique is truly a lot of fun.
Adapting Lenses – How and Why it Works
So, why can you use all these old lenses, and are there any limitations and problems with the process? Let’s dig in. First, there are a few things to understand about how lenses are designed for a camera system.
The distance from the film plane or digital sensor to the point where the lens and camera mounts interface is called the Register Distance or Flange Focal Distance. Each camera mount is designed around a standard register distance, and lenses are designed to operate with that register distance in mind. If the lens is mounted too close to the sensor plane, then the lens has difficulty focusing on closer subjects, and will focus beyond infinity (such that everything is out of focus).
Typical 35mm SLR lens mounts have register distances generally between about 38mm and 50mm, which is necessary to maintain clearance for the mirror. Typical rangefinder systems have register distances in the 25-30mm range. Mirrorless cameras, however, have very short register distances, ranging from the super short 9.2mm register of the Pentax-Q to the relatively long register of the Samsung NX system at 25.5mm. Fuji X, Sony NEX and Micro 4/3 all have register mounts between 17 and 20mm.
Since these mirrorless systems all have register distances shorter than essentially all SLR and Rangefinder systems, a simple mechanical adapter is all that’s required to properly use another system’s lenses. The adapter must be sized such that when the adapter is mounted, the distance from the sensor plane to the adapted mount is exactly the same as the adapted mount’s native register distance. See the image below for an illustration.
One key thing to remember with these adapters, however, is that they are best suited to fully mechanical manual lenses. That is, those with manual aperture rings and good manual focus helicoids. While simple adapters exist for Nikon F and Canon EF, the use of Nikon G lenses and Canon EF lenses on these simple adapters means you lose the ability to control the aperture, and none of the autofocus features work. There are some adapters that have built-in electronics and do allow for aperture control of these lenses, and in some cases autofocus and image stabilization, but they are rather expensive.