What’s the smartest way to get manual control of your camera? Get a ‘dumb’ lens!

Modern cameras aren’t really set up for manual control. You can adjust the shutter speed, lens aperture and focus manually, but you have to do this indirectly via the mode setting, command dials and manual lens focus rings that are designed more as an emergency override than a front-line control. But there is an answer.

• Articles on manual photography
• Manual photography: Why shoot manual at all?
• This is why manual controls on cameras matter
• How hard can it be to find an all-manual camera with actual DIALS?
• Which are the best cameras for manual exposure?
• The smartest way to get manual control is a ‘dumb’ lens

While you can’t do much about your camera’s design and interface, you can do something about the lens – and since this is where a lot of manual control resides, it’s definitely worth exploring some less obvious lens choices.

Obviously this requires a camera that takes interchangeable lenses. This includes both DSLRs and mirrorless cameras, but in this instance I’m going to say a mirrorless camera is better. Surprised? Well, almost by accident, mirrorless cameras are much better at handling vintage or manual lenses.

One of the reasons is that mirrorless cameras have a short distance between the lens mount and the sensor, while many older lenses are designed for cameras where this distance is larger. This means that there is space to fit adaptors to mount almost any older lens on to a mirrorless body.

Here’s my Sony A7 II with an inexpensive M42 screw mount adaptor which allows me to fit any of my collection of M42 mount SLR lenses from the 1970s and 1980s. There are no electrical or mechanical connections, but the lenses and the camera can still work together perfectly well. 

What’s a ‘dumb’ lens, and why is this not a problem?

A ‘dumb’ lens is one that doesn’t pass any information to the camera, and doesn’t respond to any of the controls on the camera. Sounds like a disaster, right?

Actually, no! The camera doesn’t need to control the lens focus mechanism or its aperture, since you do that directly on the lens. The camera can still capture the image formed by the lens without having any control over it.

You will need lenses with physical aperture rings that can be stopped down manually and don’t demand a stop-down lever on the camera body. Many SLRs of the time had levers or pins that stopped the lens down to your chosen aperture at the moment the picture was taken so that you could still focus and compose the shot at the maximum aperture, but in many cases where this mechanism is missing, the lens will default to stopped-down operation anyway.

So what are the limitations of ‘dumb’ lenses?

• A ‘dumb’ lens won’t pass any aperture information to the camera (unless it’s a modern ‘chipped’ manual lens that can communicate this information to the camera). This won’t affect the pictures, but it does mean that later on when you check the EXIF (shooting) information of your images, the aperture value will be unknown.
• A ‘dumb’ lens won’t pass any distance information to the camera. This can be significant for certain metering modes, but it’s not especially significant, especially if you’re shooting manually.
• A ‘dumb’ lens will stop down to the aperture you set and will produce a dimmer image. This would be an issue on a DSLR, but is not an issue for mirrorless cameras because they will simply increase the viewfinder brightness to compensate.
• You can’t control the lens aperture from the camera body. This means that the camera’s shutter priority mode won’t work, and the program mode won’t really work as expected either.

You can use a ‘dumb’ lens for auto-exposure!

Surprised? You might imagine that you would have to use manual exposure mode only, but in fact aperture-priority mode works too, because the camera will simply adjust the shutter speed to allow for the brightness of the image being produced by the lens.

If you’re reading an article about manual photography, this might not interest you too much – but it’s still good to know that if you have to act quickly and have no time to think properly, aperture-priority mode will work just fine.

This is what makes ‘dumb’ lenses so great for manual control

1. I can use this inexpensive adaptor to fit vintage lenses on to my Sony A7 II body without worrying about contacts, compatibility or anything else. As long as the adaptor is the right thickness to allow infinity focus – and, naturally, that’s one of the first things they’re made for – then all you need is a mount that fits the camera body on the back and one that fits the lens on the front.
2. This is an old Pentax Super Takumar 55mm f/2. It’s surprisingly sharp and has a nice ‘look’ to its images. It was designed before anyone had even heard of digital cameras, but that doesn’t make any difference.
3. The aperture ring has click-stops at full and half-stop settings – not the one-third stop increments of modern lenses. There’s no communication between the lens and camera, so you don’t have to change any settings on the camera (though there may be a menu option to allow the shutter to fire with no lens connected).
4. The focus ring has a long travel on a mechanical cam which is both smoother and more precise than the fly-by-wire electronic manual focus operation of modern lenses.
5. There’s also a distance scale – another rarity today! Be careful, though, because most adaptors are designed with a little slack so that optical infinity focus is usually a little before the infinity marker on the lens. You can use these distance scales, but do carry out your own tests to make sure where infinity focus actually occurs on the scale.
6. These depth of field index markers are the unique party trick of ‘dumb’ lenses. They show you the near and far limits of depth of field for each lens aperture. For example, if I focus at 10m using an aperture of f/8, I can see that the depth of field should extend almost to infinity at its far limit and down to around 6-7m at its near limit.

‘Dumb’ lenses are smarter than they look

It’s this visual connection between the focus distance, lens aperture and depth of field that makes ‘dumb’ lenses actually rather smart. They restore proper depth of field control for zone focusing and hyperfocal focusing for landscapes, in a way that’s completely absent with modern cameras and autofocus lenses.

For example, if I need maximum near-to-far depth of field for a landscape shot, I can set the lens aperture to f/16 then rotate the focus ring so that the outer f/16 index marker lines up with infinity on the focus ring. I can see from the inner f/16 marker that the image should be sharp right down to a distance of 3m. Modern lenses and AF systems are designed to focus on one thing only, not ‘between’ things to exploit the depth of field.

Depth of field control has always been a key photographic tool, and despite their more primitive operation, ‘dumb’ lenses are actually far better at this than modern ones. Do keep in mind my earlier comments about focus distance scale accuracy via adapters, though.

Should you get new ‘dumb’ lenses or old ones?

Lens maker Voigtländer makes a large number of manual focus lenses for modern cameras. They’re not especially cheap but not expensive either by modern lens standards. Chinese maker Laowa makes manual lenses too, as do a number of other Chinese makers.

If a lens is made for a specific mount you can probably expect good focus distance scale accuracy, and it’s only when you’re using mount adapters – especially inexpensive ones – that you might need to check.

So if you prefer new equipment rather than vintage, I’d suggest checking out Voigtländer’s lens range to start with. But if you decide to go the vintage route via lens adapters instead, I think you’ll be surprised at how good some of these old lenses are, and how quickly you can adapt to manual focus and exposure.