Finer Points: It's time to add some AI to manual focus. Here's a way to do it

There are still situations where manual focusing is needed. Why have MF Assist tools not evolved along with the rest of camera tech? Photo: Matt Waller If there’s a cutting edge to the current camera industry, it’s autofocus. Every camera release seems to overtop the last in new technologies, processing power and menu pages devoted to tracking, subject recognition, eyeball monitoring and other esoteric formulas for having the camera focus for you. In all hoopla, the forgotten child of the digital camera world has been Manual Focus (MF) Assist. For the most part, today’s cameras are still using the same clunky, limited MF Assist tricks as five or ten years ago. And they never worked that well. Finer Points: Ideas for issues big and small About this series:Innovation pushes our industry and the craft forward. This series aims to share solutions, rooted in research and sourcing, to some of our biggest and smallest problems in the world of photography and video. Read the entire series here. One might ask, does anyone need to manually focus anymore? Haven’t we reached the point of letting the AF system gently remove our fingers from the focus ring with a discreet ‘Allow me,' trusting that it will identify and follow our chosen subject every time? To that I say, ‘Well, yes, in normal life certainly.’ But there remain various sticky situations when we have to shoot through a mesh fence, or into a tangle of brambles, or insist on making a photo of the reflected city in the restaurant window and not the patron behind it. In short, the world still coughs up circumstances in which we need to take control back and focus ourselves. I might also point to the resurgence of retro pleasures. The last few years have seen a revolution in the availability of inexpensive manual focus lenses from third-party manufacturers such as TTArtisan, 7Artisans, Mitakon, Pergear and others. Vintage manual lenses are also finding new life on mirrorless cameras thanks to an avalanche of adapters that allow fitting old glass to modern bodies. But this provides a clue as to why MF Assist tools have been left all but frozen in time. Why should camera makers, after pouring development money into AF systems and lens motors, want to help you use budget glass from other companies? Thus even deep-pocketed enthusiasts manually focusing their flagship Nikkor Z 58mm F0.95 Nocts are coming up against Magnify and Peaking systems that in many cases are harder to use and less precise than the split prism on early SLRs or Leica’s 1930’s-era rangefinder patch. For those unfamiliar with Magnify and Peaking, they represent the standard industry features to help users achieve focus when manually turning the lens ring. All I can say is that I’ve never gotten a tack-sharp photo using Focus Peaking. Magnify, or ‘punching in,’ remains the MF Assist tool of choice: you hit a button to zoom in on a portion of the frame, then, with the image zoomed in, it's easy to see when lines are sharp. However, in most cases you lose your framing and must de-magnify to check composition, an extra button push before shooting that may nudge your focus out again or make you miss the moment, especially with a skittish target like a bird. Focus peaking, which originated in the video industry, is the other most implemented approach: with this you keep your full view of the scene but glowing lines appear around the objects of sharpest contrast, highlighting what’s in focus – along with, usually, a lot of other stuff just out of it. Different camera makers have different quality peaking; all I can say is that I’ve never gotten a tack-sharp photo using focus peaking. Autofocus cost me this shot. But would magnify or focus peaking have helped? Photo: Matt Waller But all is not lost in the digital world. I will give a shout-out to two well-intentioned, if imperfect attempts. Fujifilm cameras offer some specialty MF Assist tricks like Digital Split Prism. In my limited experience, however, none of them were as clear to use as good old ‘punching in.’ Fujifilm's Digital Split Prism (left) and Canon's Focus Guide (right) represent some of the few attempts to update Manual Focus Assist tools. Another new tool is Canon’s Focus Guide feature, available on its R-mount cameras, which tackles the problem by superimposing a trio of arrows on the frame; you line them up by turning the ring, and a focus box below them turns green when the target is sharp. It works quite well, but the difficulty comes, of course, when you need to move the box to keep up with a moving subject. I have an idea for a new MF Assist tool that will take advantage of modern cameras’ intelligence: combine focus peaking with subject detection. Yes, AI MF Assist. Let manual focusing have a share of the camera’s subject-recognition smarts. Have the Peaking outline appear only on eyes, only on birds, only on…er, motorbikes. (Hey, motorbikes move, that actually would be very helpful as you try

Finer Points: It's time to add some AI to manual focus. Here's a way to do it

There are still situations where manual focusing is needed. Why have MF Assist tools not evolved along with the rest of camera tech?

Photo: Matt Waller

If there’s a cutting edge to the current camera industry, it’s autofocus. Every camera release seems to overtop the last in new technologies, processing power and menu pages devoted to tracking, subject recognition, eyeball monitoring and other esoteric formulas for having the camera focus for you.

In all hoopla, the forgotten child of the digital camera world has been Manual Focus (MF) Assist. For the most part, today’s cameras are still using the same clunky, limited MF Assist tricks as five or ten years ago. And they never worked that well.

Finer Points: Ideas for issues big and small

About this series:
Innovation pushes our industry and the craft forward. This series aims to share solutions, rooted in research and sourcing, to some of our biggest and smallest problems in the world of photography and video.

Read the entire series here.

One might ask, does anyone need to manually focus anymore? Haven’t we reached the point of letting the AF system gently remove our fingers from the focus ring with a discreet ‘Allow me,' trusting that it will identify and follow our chosen subject every time? To that I say, ‘Well, yes, in normal life certainly.’ But there remain various sticky situations when we have to shoot through a mesh fence, or into a tangle of brambles, or insist on making a photo of the reflected city in the restaurant window and not the patron behind it.

In short, the world still coughs up circumstances in which we need to take control back and focus ourselves.

I might also point to the resurgence of retro pleasures. The last few years have seen a revolution in the availability of inexpensive manual focus lenses from third-party manufacturers such as TTArtisan, 7Artisans, Mitakon, Pergear and others. Vintage manual lenses are also finding new life on mirrorless cameras thanks to an avalanche of adapters that allow fitting old glass to modern bodies.

But this provides a clue as to why MF Assist tools have been left all but frozen in time. Why should camera makers, after pouring development money into AF systems and lens motors, want to help you use budget glass from other companies? Thus even deep-pocketed enthusiasts manually focusing their flagship Nikkor Z 58mm F0.95 Nocts are coming up against Magnify and Peaking systems that in many cases are harder to use and less precise than the split prism on early SLRs or Leica’s 1930’s-era rangefinder patch.

For those unfamiliar with Magnify and Peaking, they represent the standard industry features to help users achieve focus when manually turning the lens ring.

All I can say is that I’ve never gotten a tack-sharp photo using Focus Peaking.

Magnify, or ‘punching in,’ remains the MF Assist tool of choice: you hit a button to zoom in on a portion of the frame, then, with the image zoomed in, it's easy to see when lines are sharp. However, in most cases you lose your framing and must de-magnify to check composition, an extra button push before shooting that may nudge your focus out again or make you miss the moment, especially with a skittish target like a bird.

Focus peaking, which originated in the video industry, is the other most implemented approach: with this you keep your full view of the scene but glowing lines appear around the objects of sharpest contrast, highlighting what’s in focus – along with, usually, a lot of other stuff just out of it. Different camera makers have different quality peaking; all I can say is that I’ve never gotten a tack-sharp photo using focus peaking.

Autofocus cost me this shot. But would magnify or focus peaking have helped?

Photo: Matt Waller

But all is not lost in the digital world. I will give a shout-out to two well-intentioned, if imperfect attempts.

Fujifilm cameras offer some specialty MF Assist tricks like Digital Split Prism. In my limited experience, however, none of them were as clear to use as good old ‘punching in.’

Fujifilm's Digital Split Prism (left) and Canon's Focus Guide (right) represent some of the few attempts to update Manual Focus Assist tools.

Another new tool is Canon’s Focus Guide feature, available on its R-mount cameras, which tackles the problem by superimposing a trio of arrows on the frame; you line them up by turning the ring, and a focus box below them turns green when the target is sharp. It works quite well, but the difficulty comes, of course, when you need to move the box to keep up with a moving subject.

I have an idea for a new MF Assist tool that will take advantage of modern cameras’ intelligence: combine focus peaking with subject detection.

Yes, AI MF Assist. Let manual focusing have a share of the camera’s subject-recognition smarts. Have the Peaking outline appear only on eyes, only on birds, only on…er, motorbikes. (Hey, motorbikes move, that actually would be very helpful as you try to follow them from behind the fence.)

With the AI smarts behind it, the peaking outline would remain on the detected subject as they hop through the branches or feint through the defenders. It would allow a skilled camera operator to keep even a moving subject in focus without losing composition.

Let manual focusing have a share of the camera’s subject-recognition smarts. Have the Peaking outline appear only on eyes, only on birds, only on…er, motorbikes.

A step in the right direction is Canon’s aforementioned Focus Guide feature; on the R-Mount cameras you can combine it with Eye Detect, which automatically places the target box over the eye, and it does move with the eye. That’s the right track! But why stop at eyes, Canon, when your cameras are bursting with their subject detection bestiaries?

Since I'm picking the pocket of modern camera tech for focus peaking, I'll also add that it would be nice to nab some phase detect intelligence for it, to improve its precision. Peaking has always been based on contrast, but given that it's trying to illustrate your literal depth of field, the depth awareness of the scene that the camera already has from its phase detect pixels seems like worthwhile info to share. (Of course the camera has to have phase detect AF, but more and more cameras are starting to have it.) I could then see peaking represented on-screen in different colors to represent gradations of useful focus, say white for the broad F4 stroke of 'almost' with a thin central outline of red for 'tack sharp.'

With these two pieces in combination, peaking would finally replace ‘punching in’ as the MF Assist tool of choice.

Imagine you’re looking down a rank of Buckingham Palace guards and trying to focus on one in the middle. The face detect AF system is hopelessly confused, and regular CDAF focus peaking is outlining too much. But with AI/PD MF Assist you just turn the ring as the outline hops from face to face until only the right ruddy cheek is outlined, and snap the perfect shot.

Imagine the above shot at F1.8. Would your AF face detection find the right face? Would your MF Assist tools be fast enough to use? AI MF Assist would solve both problems.

Photo: Mr G's Travels (creative commons)

The camera smarts for it already exist. Its implementation merely requires the industry to spare a moment from their frantic AF wars to remember us manual focusers, over there in the brambles, behind the mesh fence.

What’s your take? Do you agree that subject detection would improve MF Assist? Or do you have a better solution? Let us know in the comments.