If you spend any amount of time reading online discussions about the GoPro Mission 1 and Mission 1 Pro, you'll quickly run into two different focus debates.
Some people point out that the cameras don't focus particularly close. The practical near-focus limit is around 60 cm / 24 in, with optimum focus closer to 1.5 metres.
Others notice that objects in the very far distance are not perfectly sharp or in focus.
These are not two unrelated quirks. They are two ends of the same optical compromise.
The Mission 1 and Mission 1 Pro use fixed-focus lenses. Like most other action cameras, they can't move the lens elements back and forth based on the scene you're filming, so GoPro had to choose one permanent focus position and rely on depth of field to keep everything around it looking sharp.
A bigger sensor changes the focus equation
For years, one of the most common requests from GoPro users has been a larger sensor. Larger sensors can bring real advantages, particularly in low light and overall image quality, but there is an optical tradeoff that doesn't get talked about nearly as much.
For the same field of view and framing, a larger sensor requires a longer focal length. At the same f-number, that means less depth of field.
In plain English, you don't get quite as much of the world in sharp focus at once.
Older, smaller-sensor GoPros had an enormous depth-of-field advantage. Their lenses could keep subjects from relatively close to the camera all the way out toward the horizon looking sharp without asking very much of the optics.
Move to a much larger sensor and that comfortable zone of sharpness gets narrower.
Think of depth of field as a blanket of acceptable sharpness. If you pull a small blanket closer to your head, it no longer covers your toes. Pull it back toward your toes, and your upper body isn't covered anymore.
The larger sensor gives GoPro a smaller blanket to work with. They still get to decide where to put it, but they can't make it cover everything from your fingertips to infinity.
Physics can be annoyingly unwilling to negotiate.
This is one of those cases where getting something people have been asking for also exposes a tradeoff they may never have had to think about before.
Fixed focus doesn't mean one distance is sharp
The term fixed focus can be a little misleading.
It can sound as though there is one exact distance where everything is perfectly sharp, with everything in front of or behind it immediately becoming blurry. That's not how it works.
There is a distance where the lens produces its best optical focus. With the Mission 1 series, that appears to be roughly 1.5 metres. Subjects closer and farther away can still look sharp because they fall within the lens's depth of field.
Sharpness changes gradually as you move away from the optimum focus distance. There isn't a line painted on the ground where everything goes out of focus.
That's important, because it explains what is happening at both ends of the Mission 1's focus range.
The close end: why the Mission 1 doesn't focus as close as older GoPros
The practical near-focus limit of the Mission 1 and Mission 1 Pro is around 60 cm / 24 in.
For most action-camera use, that isn't particularly restrictive. Put the camera on a helmet, bike, car, drone or tripod and most of what you're filming is comfortably farther away than 60 cm.
Turn the camera around and hold it at arm's length, though, and 60 cm suddenly becomes much more relevant.
The same applies when filming products, food, equipment, hands, instruments or anything else fairly close to the camera.
This is one of the less obvious consequences of moving to a larger sensor. The greater image-quality potential comes with less depth of field, so GoPro had a narrower useful focus range to distribute between nearby subjects and distant ones.
There also isn't a hard cliff at 60 cm.
At 59 cm the camera doesn't suddenly stop focusing. As you move closer than the normal near-focus range, fine detail progressively becomes softer. How noticeable that is depends on the subject, resolution, viewing size and how closely you inspect the image.
A face viewed on a phone may still look perfectly acceptable closer than 60 cm.
Tiny lettering on a product being examined at full resolution is much less forgiving.
Professional photographers often use cameras with much larger sensors, where shallow depth of field is easier to achieve. They can use this deliberately, for example by keeping a person's face sharply in focus while allowing the background to blur. It can really make a subject pop.
The other end of the tradeoff: infinity focus
The close-focus limit is easy to demonstrate. Hold something 30 cm from the camera and the softness is obvious.
The other end of the same focus range has caused just as much debate.
At the far end of the focus range, very distant subjects sit close to the edge of the Mission 1's usable depth of field. They can still look very good, but fine detail can begin to soften as distance approaches infinity.
That does not mean infinity is simply "out of focus."
Depth of field extends both in front of and behind the point of best focus. Distant subjects can therefore still look very sharp even though they are approaching the far edge of the camera's useful focus range.
This distinction becomes much easier to see when people start looking at high-resolution stills at 100% on a monitor.
A distant building may contain slightly less fine detail than something several metres from the camera, while the complete photograph still looks excellent at normal viewing sizes.
Both of these statements can therefore be true:
- The Mission 1 and Mission 1 Pro can produce very sharp distant images.
- Very distant subjects sit close to the far edge of the cameras' usable depth of field.
There is no contradiction there.
The Mission 1 series simply gives us enough resolution to examine optical compromises that would often have gone unnoticed on older action cameras.
Could GoPro have shifted the focus range farther out?
Yes.
But moving the focus range farther toward infinity would also move the near end of the useful focus range farther away.
GoPro had to decide where to place that limited depth-of-field "blanket." Pull it farther toward the horizon and you gain something at the far end, but your feet start sticking out at the close end.
The tradeoff is physics. Where GoPro chose to place the fixed focus is engineering.
That distinction matters because some criticism of the Mission 1 series treats the far-distance softness as though GoPro simply set the lens incorrectly. The reality is more complicated.
GoPro could have shifted the useful focus range more aggressively toward distant scenery, but that would have come at the expense of close shooting.
Given the range of things people actually do with action cameras, putting optimum focus somewhere around 1.5 m is a pretty understandable decision.
A camera optimized more aggressively for very long distances might make distant mountains a little sharper under close inspection, while also requiring unusually long arms for anyone trying to film themselves.
Moving the whole focus range closer
If you want to use the Mission 1 or Mission 1 Pro for genuinely close subjects, there is a simple optical solution: add a positive diopter in front of the camera.
A +2 close-focus lens has an optical power of +2 diopters. Rather than changing anything inside the camera, it bends the incoming light so the existing fixed-focus position corresponds to a much closer subject.
Using the Mission 1 series' roughly 1.5 m optimum focus distance, a +2 diopter moves optimum focus to approximately:
37.5 cm / 15 in
The stock near-focus limit of roughly 60 cm moves to approximately:
27 cm / 11 in
The entire focus range moves closer, so distant subjects are no longer what the camera is optimized for while the close-focus lens is installed.
For vlogging, handheld filming, product shots and other nearby subjects, that's exactly the point.
For distant shooting, simply remove the close-focus lens.
A simple way to add close focus to the Mission 1 and Mission 1 Pro
Our GoPro Mission 1 / Mission 1 Pro Close Focus Lens + 58mm Filter Adapter fits over the camera's original lens cover and adds a standard 58mm filter thread.
Use it with the +2 close-focus lens when you want to bring the focus range much closer, or swap in another standard 58mm photographic filter. When you don't need it, the entire adapter can simply be removed.
No modification to the camera is required, and the original GoPro lens cover remains in place.
So did GoPro get the focus wrong?
We don't think that's a particularly useful way to look at it.
GoPro (and many users!) wanted a larger sensor while keeping an extremely wide lens, a relatively bright aperture, fixed focus, rugged construction and the tiny form factor expected from an action camera.
Those requirements create compromises.
The Mission 1 and Mission 1 Pro use a focus position that strongly favours the distances at which action cameras spend most of their lives, while still keeping arm's-length and relatively close shooting reasonably practical.
The result is very good sharpness across most normal shooting distances, a longer near-focus distance than many older GoPros, and very distant subjects sitting closer to the far edge of the usable depth of field.
They're all consequences of the same optical decisions and physics.
Once you understand the relationship between sensor size, focal length and depth of field, the Mission 1 series' focus behaviour makes a lot more sense.
Related: Learn how ND filters work with the Mission 1 and Mission 1 Pro in our Mission 1 ND filter guide.