camerapapi Loc: Miami, Fl.

If you want the sharpest images the best way to achieve them is through manual focus. The BBF is convenient because it separates AF from the shutter. It does not make AF more accurate.

Longshadow Loc: Audubon, PA, United States

Thomas902 Loc: Washington DC

BBF? "What's not to like?"

While I use BBF almost exclusively there are issue others have yet to address....
Sooooo.... my experience in a dark studio it eliminates that authentation "Beep" when the camera achieves "Lock" in S (Single Focus Mode) mode since BBF requires C (Continuous Focus Mode).

Now before you say that's silly, please understand in a dark studio painted flat black with black seamless and having the talent illuminated with only modeling lamps can make focus conformation a challenge...

I shoot commercially and time is money... I have a team on set and use a huge mirror behind the me for the talent to see him/her self while showcasing a designers textile artistry... They ONLY can do this when what they see is what I'll get... The audio beep (turned to high max volume) provides both me and the talent feedback that assures we both are in aware of focus lock... Now this only works for static poses and since my visual statement is primarily dance oriented I nearly always am shooting in Continuous focus mode with BBF enabled.... It's a matter of matching the right technique to the situation at hand...

This is the only major down side of BBF I've experienced... And it is highly unlikely that UHH folks will be shooting in a flat black studio with illumination only by modeling lamps which track with power settings...

Critical focus isn't optional when shooting commercially it is absolutely mandatory.... Any technique that aids this is to be cherished... BBF being one of them...

Food for thought... transitioning to BBF is a challenge regardless of what others might say... muscle memory comes from time in the saddle... As anyone who plays a musical instrument knows... Give it time folks... like weeks, even mouths before you pass judgement, k?

Jersey guy Loc: New Joisey

[quote=billnikon]I shoot a lot of birds. I hope those birds you "shoot" aren't on the endangered species list.

Bill_de Loc: US

Just a couple of points. BBF itself does not require continuous focus. The Beep can be turned on and off.

For your workflow, what you are doing makes a lot of sense.


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Rich1939 Loc: Pike County Penna.

Ha! I use and love BBF
I'm left eye dominate and will be 80 years old in a couple of weeks. I have found zero problems ergonomically and the only mental draw back is keeping my temper when I read assholistic comments

Blurryeyed Loc: NC Mountains.

I use BBF on all my cameras, the biggest and I think only advantage is that you can focus and then recompose, you don't have to worry about the camera refocusing on an unintended focal point when you pull the trigger.

lnicol3702 Loc: Stuart FL

So a Question.... when I have the camera on a tripod and using a remote shutter release how does the BBF work then?

amfoto1 Loc: San Jose, Calif. USA

Back Button Focus (BBF) does NOT make your photos sharper. It simply puts you in more full control of where and when the camera and lens focus.

First, some background info you need to know...

Your 80D has two primary autofocus modes: One Shot and AI Servo (it also has AI Focus, but ignore that for now).

One Shot is for stationary subjects. When you half press the shutter release button OR press the AF On button on the back of the camera with your thumb, autofocus (AF) starts, uses the selected AF points to acquire focus on the subject, stops and locks as soon as focus is achieved, then gives you Focus Confirmation (a green LED in the viewfinder lights up... also an audible "beep" and/or a "red flash" in the viewfinder, if you have those features enabled). If your or the subject move.... if the distance between you changes... you have to lift off the button and re-do AF. This is impossible when a subject is moving any faster than a slow crawl. By the time you've refocused on a moving subject, it will again have moved out of focus.

AI Servo is a form of continuous focus, especially for moving subjects. You start it up the same way... half press of the shutter release or by pressing the AF On button... but it constantly updates and tracks moving subjects, changing focus as the subject distance changes, and never stops and locks until you release the button. There is no Focus Confirmation in AI Servo... it's simply not possible because the focus is continuous. (Some cameras have an indications in the viewfinder that AF is working, but it's not confirmation that focus has been achieved... you have to trust that it has based upon your experience with the camera and lenses, as well as your judgment of what you see in the viewfinder.)

AI Servo can also be used with stationary subjects. If it works for both stationary and moving subjects, why not only use that focus mode? Well, there's a problem that AI Servo can't be used for some common techniques that are done with stationary subjects, such as "focus and recompose". This is where you focus, then change the composition so that the subject is off-center. If you do that while using AI Servo and the half-press shutter release, the camera will shift focus away from the subject as soon as you recompose and take the AF point off it, before you can take the shot. Not a good thing! You'll end up missing most shots that way... unless you stop shooting for a moment and switch to One Shot, which isn't as versatile as AI Servo.

80D has a third choice called AI Focus, which might solve this quandary... but actually doesn't. AI Focus isn't really a separate focus mode. It's automation that the camera is supposed to determine if the subject is moving or stationary, then switch to use the correct focus mode: One Shot for stationary, AI Servo for moving. Maybe it's better on newer cameras like 80D, but years ago when I experimented with AI Focus on older models I found it caused a slight pause or delay while the camera was deciding what to do, that it sometimes chose the wrong mode, and that it often failed to switch modes if a subject started or stopped moving. I had a lot of missed focus images when I tried to use AI Focus. (Note: It might be a clue, the top-of-the-line, pro-oriented 1D-series Canon cameras don't even have AI Focus mode... They only have One Shot and AI Servo.)

The solution is BBF. And on the 80D (and many other Canon), it's already partly set up for you. To fully use BBF, all you have to do is disable AF from the shutter release button. That's done in the menu, on the button and dial customization page, the first item is the shutter release button. Navigate there and change it from the default, left hand "AF" or "Focus" to the middle "Meter" setting. Once this change is made a half-press of the shutter release will still start the camera's light meter and activate IS on lenses that have it, but it will no longer activvate AF. That's now done by pressing the AF On button with your thumb. (Note: This also starts metering and IS, if you aren't half-pressing the shutter release at the same time.)

Once set up, you can start and stop AF at will, by pressing or releasing that AF On button with your thumb. This way you can use AI Servo full time, with both moving and stationary subjects, and can still use techniques like focus and recompose (simply stop focus before refocusing). You also can use it to "dodge" obstructions that a moving subject momentarily passes behind and some other techniques. BBF is particularly popular with sports photographers, because it makes them "ready for anything" without having to pause and reset their cameras.

It takes a little practice to get accustomed to BBF... But once you do, chances are you'll never switch back. Once I learned it around fifteen years ago, I've used it on all my Canon cameras, regardless of what type of subject I was shooting.

The only real "down side" to BBF is that there's no Focus Confirmation (it's not possible with continuous focus). You have to rely on what you see on the viewfinder's focus screen (which is too small to be 100% certain) and to trust yourself, the camera and the lens. BBF also may be a problem if you lend the camera to someone who doesn't know how to use it.

Something else that can help a lot... in conjunction with BBF... is to always use as few AF points as possible. The more of the 80D's 45 AF points you have active, the greater chance that the camera will focus somewhere other than where you want it to focus. A single AF point is ideal, but it's more work for you... requiring you to keep that AF point where you want the camera and lens to focus. With moving subjects, that can be tricky! So there are times when more points might be needed, such as the Zone and Large Zone AF patterns your 80D offers... maybe even "All Points/Auto" on some rare occasions. But it's best to use these multi-point setups in situations where the subject is well separated from any background and there are no obstructions between you and them, little to distract the AF system from the subject.

Personally I use Single Point most of the time. With BBF and some other focus fine tuning, shooting sports that I'm familiar with and have lots of practice, I get upwards of 98% of my shots acceptably in focus. That percentage drops a bit with unfamiliar and fast moving subjects or when it's necessary to use additional AF points due to erratic movements and changes in direction. But even then I get higher percentage than I did with any other focus method. I only switch to multi-point patterns is certain situations (my 7D Mark IIs have more points and several more patterns than your 80D). When I'm doing critical focus work of stationary subjects, I'll switch to Live View where I can magnify the image on screen.

Another thing that's key to success is the lens focus drive system. Canon's USM or "ultrasonic" lenses are their fastest focusing and, when combined with BBF and good technique, can keep up with all but the fastest moving subjects. Among third party lenses, Sigma's HSM and Tamron's USD are focus drive designs that should give similar performance. Canon's STM or "stepper motor" focus drive is also reasonably fast, but USM is 2X to 4X faster. The slowest focusing Canon lenses use a "micro motor". Those tend to be the least expensive and can be identified by not being marked either "STM" or "USM".

As far as I know, only one Canon lens model has been produced with all three types of focus drive: the EF-S 18-135mm f/3.5-5.6.

The original and EF-S 18-135mm "II" use a micro motor focus drive (and an older optical formula).

The EF-S 18-135mm "STM" uses both the faster/quieter stepper motor and has improved optics.

The EF-S 18-135mm "USM" uses the same optics, but has Canon's latest "Nano USM" focus drive and is said to focus 2X to 4X faster than the STM version of the lens.

There are a few Canon USM lenses that aren't particularly fast focusing (such as the EF 85mm f/1.2L II, EF 100mm Macro and EF 180mm Macro). But those are rather specialized... portrait and macro lenses that don't need to be fast focusing. Paired up with a camera that has top of the line AF system and is set up properly by the user, the majority of USM lenses give near instant focus in all but the most difficult situations. Larger aperture lenses also may help... up to a point.

In many Canon cameras, the center AF point gives higher performance with lenses that have an f/2.8 or larger max aperture. (The super fast f/1.2 lenses are an exception, due to the very large, heavy elements they use, as well as their potential for very shallow depth of field which calls for precision instead of speed. It's similar with macro lenses.)

However, when shooting fast action it also can help to stop lenses down a bit, for some extra depth of field that will naturally "correct" minor focus errors. With my f/2.8, f/2 and faster lenses, I often set f/4 or f/5.6 for this reason. It depends upon distances, too... but using a large aperture lens wide open can make for too shallow depth of field, which in turn makes focus accuracy super critical.

Hope this helps!

Longshadow Loc: Audubon, PA, United States

On my camera, the same. I have to pre-focus or manually focus.
The "shutter" button on the remote does whatever the shutter button on the camera is set to do, or not do.

lnicol3702 Loc: Stuart FL

But I normally have my thumb depressing the BBF button at the same time I push the shutter button so obviously I don't want to touch the camera if its on the tripod and I'm using the remote shutter?

Longshadow Loc: Audubon, PA, United States

Pre-focus.
When not on a tripod, I only have my finger on the BBF button to focus. Then I usually re-compose & nail the shutter. I use single point center focus.

nadelewitz Loc: Ithaca NY

The SAME autofocus sytem is at work whether using BBF or the shutter button to initiate focus. The Facebook articles are crap, if the only camera-use difference is between those two options.
If the camera is supported/held the same way there would be no difference in quality of focus.

MAYBE, just MAYBE, BBF could give "better" focus if....
You tend to move the camera downward when pressing the shutter button. Having the camera focus while it is moving is a problem. With BBF, focus is set before any camera movement.

I'll let an 80D user tell you what menu lets you setup BBF. It's too bad camera makers don't use the term Back Button Focus on their settings menus. You have to choose from different shutter-button reassignment options.

chasgroh Loc: Buena Park, CA

I set the shot up (trying to get f8), then stand right next to the person who's gonna pull the trigger, focus, carefully hand the camera to the surrogate and have him/her take a test shot. I then make sure all is well in focusland, hand the camera back and go to my spot in the group photo. Seems to work.

Longshadow Loc: Audubon, PA, United States

Yup, it's either done with button A or button B.