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| RF 600mm f11 on EOS R5 |
The EOS R5 (and the R6 which is similar) has a very advanced autofocus system with impressive capabilities. However the system offers so many modes and options it can become quite overwhelming.
This post is an attempt to untangle the complexity leading to a systematic approach which can be applied to any usage case.
I write posts like this for myself initially. I find the process of presenting everything in readable form forces me to better understand what is going on. Hopefully other R5 users can also benefit from the material.
Capabilities
I bought my first Canon autofocus SLR in 1990 and eventually gave up using Canon DSLRs in 2010 as none of them was capable of focussing reliably on anything. The Panasonic Lumix mirrorless interchangeable lens cameras which had arrived on the scene by then delivered more accurate and consistent single shot AF so I used those for ten years. But Panasonic persisted with contrast detect AF which fell behind the PDAF and DPAF systems of Canon, Sony and Nikon when follow focussing on moving subjects. So I sold all my Panasonic gear and went back to Canon in 2020.
In 2015 Canon introduced its first model using the newly developed dual pixel autofocus (DPAF) which carries out focussing right on the imaging sensor. Canon has refined and improved the operation of the DPAF system to the extent that I rate the R5 as having one of the best AF systems of any camera, for single shot, continuous or video.
It can focus accurately anywhere on the frame at apertures as small as f22.
* Note:The RF 600mm f11 and 800mm f11 can only focus over a section of the frame, displayed in the viewfinder when the lens is mounted.
It can focus on faces and eyes, of humans, animals and birds.
It can focus on static subjects and moving subjects, including those moving at high speed, at frame rates up to 12fps (mechanical shutter) or 20 fps (electronic shutter).
It has a well designed set of controls to enable the enthusiast user to set up the camera to do any of these things on demand.
Menus
Fortunately most of the menu items relevant to autofocus are contained in the AF (magenta) submenu.
Outliers include focus bracketing which is in the Camera (red) menu screen 5.
Focus mode (AF/MF) is controlled with a slider switch on the barrel of most RF lenses. But some lenses such as the RF 50mm f1.8 lack that switch. When this lens is mounted an item [Focus Mode] appears at the bottom of AF menu screen 1.
Menu alert: Before taking photos with the R5 go to the Custom menu (orange) screen 3> Customize buttons > Multi-controllers (that’s Canon speak for the thumb stick, a.k.a. joystick) > set Direct AF point selection. Now the thumb stick will do what you want it to do which is move the active AF area.
AF menu
I will run through all the items in this menu with some comments and suggestions about each.
AF 1
* AF operation. ( Servo AF/One shot AF) This is also accessible via the Q menu. I allocate AF operation to the AF point selection button so I can quickly change this item.
* AF method. This is also available via the Q menu. I assign AF method to the M-Fn button for rapid access.
* Subject to detect > Animals (includes birds), People, No priority. This item cannot be allocated to a button or dial which is unfortunate as it is one I sometimes want to change quickly. Next best option is to allocate this to My menu and hope to remember to change when switching from people to animals.
* Eye detection. This only applies when AF method [Face detect/tracking] is in use. It toggles eye detection (in addition to face detection) on/off. I can’t think of a usage case when I would not want eye detection so I have this On.
* Continuous AF in Canon-speak means the camera forever tries to focus on something even when you don’t want it to and when you are not pressing a button. Disable this. It just runs down the battery.
* Touch and drag AF settings. The R5 has a very nice, well implemented touch screen. It does enable moving the active AF area while looking through the viewfinder. I actually don’t find this particularly useful as the screen is a stretch for my thumb to reach and the Thumb stick (multicontrollers) is so easy to reach and operate.
But for the record I have
Touch & drag AF Enable
Positioning method Relative
Active touch area Top right.
AF 2
* MF (manual focus) peaking settings. If I were to use peaking I would set level High and Color red. However the R5 has a much nicer, more precise and more user friendly way to evaluate manual focus (see below) so I switch peaking off.
* Focus guide. This is a feature I have seen only on Canon cameras and is one I always use with manual focus. It has swinging arms which coincide and go green when focus is achieved.
* AF-assist beam firing. Switch this off. It is not required and just annoys any person or other creature in front of the camera.
AF 3
This is the screen with four Servo AF cases plus Auto. In cases 1-4 there is a little description with incomprehensible pictograms and analogue scales for Tracking sensitivity and Accel./decel. Tracking. I have to confess I just leave this on Auto because I have no idea what to do with the other settings except maybe Case 1 which is described as the Versatile multi purpose setting.
AF 4
On this screen we find a number of items some of which are a bit obscure. When in doubt, I suggest leaving the item at default.
* Lens electronic MF. The options for this are described on pages 437-438 of the User Guide. This says the options here are relevant to EF lenses with electronic focus, but they seem to be applicable to RF lenses also. Basically the camera/lens combination can utilise manual focus after achieving autofocus. However I find the AF on the R5 is so reliable I never use this feature and set it Off.
* One-shot AF release prior(ity). I don’t want any out of focus shots so I set this to Focus priority.
* Switching tracked subjects. This is described on page 440 of the User Guide. I read the material three times and still don’t understand it so I just leave this at default which is the middle setting [1].
* Lens drive when AF impossible. I set this ON because sometimes with a difficult subject the camera can fail to find focus a few times then with a slight change in the subject’s position or AF area position focus is achieved.
* Limit AF methods. There are 8 AF methods available. In order to facilitate quick switching from one to another I recommend limiting those which are available. For the record I use Face detect+tracking, Spot, 1-Point, Expand AF area around and Zone.
* AF method selection control. The options here are
a) allocate AF method selection to a button (I use the M-Fn button) for direct access or
b) Press the AF area button (the rectangle with 5 dots) then turn the main dial.
Direct access via a button uses fewer actions and is less complex so I use that.
* Orientation linked AF point. This is very handy especially when photographing people with faces in the upper part of the frame. I set [Separate AF pts: Pt only]. Now the camera will remember one AF point for horizontal camera orientation and a different point for vertical orientation.
AF 5
* Initial AF pt set for face detect/tracking.
This item has generated some discussion on user forums as the meaning of the options offered is not obvious.
It seems to me that the information on page 445 of the User Guide is not as helpful as it could be.
1. When the first option is set and AF servo set, a half press on the shutter button will cause the camera to focus on the area under the white AF box which you can move to anywhere in the frame (except the extreme left and right edges) with the thumb stick. Focus is confirmed by one or many little blue squares. The camera will now attempt to (and usually does) stay focussed on the same part of the subject when framing is altered. This can be used with single shot drive mode which cancels and re-starts focussing after each shot, or one of the continuous drive modes in which case the camera will continue to track the same part of the subject.
This setting can be very useful with a subject which is basically rather predictable in content such as a group of people with focus preferred on one of them.
2. I have difficulty with the second option which seems to me overly complex. Anyway I can’t find a use for it in my work flow.
3. The third option is Auto. I use this for birds in flight. I know my subjects will be coming at me unpredictably and moving unpredictably. It is difficult just to get the bird in the frame. So the first option is not useful in this situation.
* Focus ring rotation. I leave this at default, which follows the instruction “rotate clockwise for more distance”. This makes sense to me and I suspect most people.
* RF lens MF focus ring sensitivity. I just leave this at default. However I have seen recently a review of the RF 85mm f2 lens in which the reviewer complained that this lens required many turns of the ring for manual focussing so maybe a different setting could be appropriate for some lenses..
* Multi-controller (thumb stick) sensitivity. I find default (the mid position) just fine, quick without being over sensitive. But you might like to experiment.
Canon-speak
In Canon-speak,
* Focus mode means AF or MF
* AF Operation means One shot or Servo. Servo is Canon-speak for the camera continuously re-focussing while you have the shutter half pressed (or an allocated back button pressed).
Servo AF was previously referred to as [AI Servo].
In One shot the focus box(es) are white/green.
In Servo AF the focus box(es) are white/blue.
So you can tell just by looking in the viewfinder and half pressing the shutter button whether you have set one shot or servo.
AF Method refers to [face detect/tracking] or spot, 1-point, expand AF area, Zone.
I find the concept of AF method a bit confusing. The options spot, 1-point, expand area, zone etc are straightforward enough and just represent different size/shapes of the active AF area.
The camera will focus on whatever part of the subject is covered by the AF area in either one shot or servo operation. I find I have to be careful with small subjects to ensure that the AF area box is smaller than the subject. If the AF area box is larger than the subject and if the subject is dark and the background bright, the camera will focus on the background.
All camera autofocus systems prefer to focus on bright, contrasty bits of the scene if they can find such.
Face/eye detect/tracking is a different kind of AF mode which operates over the whole frame (with most lenses) and uses a type of artificial intelligence to identify particular types of subject and to maintain focus on an identified subject as it moves in three dimensions.
Sony cameras enable face/eye detect while 1-point, zone or Sony equivalent is in use. Canon goes about things in a different way.
It is possible to invoke [Eye detection AF] (it can be allocated to a button and is not the same as [Eye AF]) while the camera is using one of the AF area methods. I allocate [Eye detection AF] to the AF-ON button and if I hold the AF-ON button down the camera will track an eye after it finds one if Servo AF is in use.
If this all sounds complicated, yes it is and that’s why I put together this post.
Is it excessively complicated ? It certainly is and all the camera makers should streamline the number and complexity of focus options offered to make the whole process of operating the camera more user friendly.
Note: Most mirrorless camera AF systems can focus on textures or vertical lines (camera held in landscape orientation) but not on perfectly horizontal lines. There are no cross type AF sensors in the current iteration of Canon DPAF. (or Sony or Nikon PDAF or Panasonic CDAF)
There are rumors that Canon might introduce Quad pixel AF (QPAF) at some future time to overcome this very minor issue which I suspect is rarely even noticed by most users. Samsung has implemented diagonal DPAF on the green sensitive pixels of its smart phone cameras to achieve the same thing.
Back button focus
There are some enthusiastic promoters of BBF but I am not one of them because
a) BBF requires two buttons to take a picture when one (the shutter button) does the job just fine. Fewer actions, less complexity.
b) The opportunity cost of allocating a back button to focus is that it cannot be used for another purpose.
For the record, BBF can be allocated to a button, usually the AF-ON button. The operation of shutter button half press has to be changed from the default which is [metering +AF] to just [metering]. (see Custom menu>Customize buttons).
Usage cases
Please take these suggestions as a starting point for a process of discovery. They are not prescriptive and will probably evolve over time..
Static subject
This is the easiest subject for any AF system. Just make sure the active AF area does not overlap the subject onto the background.
AF operation , one shot
AF method, spot or 1-point.
Tableau style scene with movement within the frame
This could be a group of people with all or some moving in the frame with one required to be in sharp focus.
There could be several approaches each of which could work well.
One is to use One-shot AF operation, place the spot or 1-point AF area over the person to be sharp and press a pre-assigned button for eye detection AF.
This will track the identified subject and work in drive mode single or continuous.
Another approach is to set AF method to face/eye detect+tracking and use option 1 on AF 5. Start the tracking process with a half press shutter button with the AF frame over the desired subject.
Bird in a bush
This gets many questions on user forums.
One approach is to set AF operation single or servo, AF method to spot and move the AF frame around with the thumb stick until it is on the bird. Try pressing the button which activates Eye AF to see if the system can pick up the eye.
Another approach is to set AF method to face/eye detect+tracking (remember to set subject to detect to Animal (works for birds)), with option 1 on AF 5.
Experiment a lot to gain familiarity with the camera’s behaviour and likely capabilities.
Predictable motion
This might be race cars on a track for instance. When camera companies launch their new products they sometimes have trained falcons or similar fly on command from one known point to another known point.
Use AF operation Servo, Drive mode High speed continuous or High speed continuous+. Experiment with AF method. Face/eye detect+tracking can work as can any of the larger AF area methods such as zone. Just watch out if using zone that the camera might decide to focus on something closer than the subject if the AF frame overlaps it. Large zone/horizontal could be useful in this case.
I find it difficult to keep smaller AF frame sizes on the subject.
Unpredictable motion
This is your classic birds in flight (BIF) situation. I find a fast shutter speed, servo AF, drive mode high speed continuous+ and face/eye detect+tracking and option 3 Auto in AF 5.1, can work well. Until it doesn’t when a quick switch to zone or expand AF area:around can sometimes save the day. That is why I have direct access to AF method on the M-Fn button.
BIFs require a great deal of practice. Just keeping the bird in frame is a challenge.
Unpredictable motion with distractors
This is the typical situation with team sports and is possibly the most difficult challenge for both photographer and AF system. You want to hold focus on the player with the ball and not have the AF system distracted by the other players running about all over the place and getting between the subject and camera.
Probably the best technique is to use AF operation servo, Drive mode High speed continuous, Face/eye detect+tracking with option 1 in AF5.1, Initial AF pt set.. Put the AF frame over the subject and half press the shutter button to initiate tracking.
Professional sports photographers often like to use back button focus to initiate tracking.
Much practice is required even with the best available equipment.
Custom shooting modes
Users who frequently encounter one of these usage cases can profitably congregate the required settings on one of the C1, C2, C3 Custom shooting modes.
That’s enough for this post I think.