EOS R5 or R6 Shutter Button Metering Function When Using Back Button Focus

[musicmaiden]

Hopefully you guys will put another question to rest that I have had about Back Button Focus:

Using the R5 or R6, Manual Mode, Servo, using Eye-Detect on AF-ON, Face Detect with Tracking on *, and Spot AF on the Shutter Button (so focus and metering enabled). My reason for leaving Spot on the Shutter Button is the ability to use my thumb to move the Focusing Point with the "joystick".  My question is this:  when I use the Back Buttons for Focusing, can I assume that the Back Buttons already take care of the metering and  there is no metering or other "technical"  conflict when then pushing the shutter button to take the picture? 

Any other things to consider when setting up for BBF? Fastest way to switch from Animal to Person Subject besides getting the R3? 

[stevet1]

musicmaiden,

I could be wrong, but I think the metering stays with the shutter button.

It's only the focusing that gets moved to the back button.

Steve Thomas

[Waddizzle]

You can answer your own questions when you setup BBF.  You assign the functions that you want the bottom to have.

In this case, your choices are (Metering Only) or (Metering + AF). 

[stevet1]

musicmaiden,

I was wrong. I apologize.

Wadizzle was right.

If you take the focus off your shutter and assign in it to the back button, that AF-ON button also meters as well as focuses. The shutter button will meter only.

If you are using the tracking method of focusing, I don't know of any "fast" way of changing from an animal to a person, but maybe someone who uses tracking can help better than I can.

Steve Thomas

[musicmaiden]

Thanks, Steve!

[Waddizzle]

That can also be programmed into any bottom that can be reprogrammed.  For example, the DOF preview button be set to completely change AF behavior when press and hold it pressed.  There dozens of functions available to play with. 

[musicmaiden]

It is hard to decide, what to put onto those buttons, isn't it? The Shutter Button is still the best to reach the joystick while focusing in Spot mode.  The DoF currently has the Aspect Ratio on it.  

Thanks, Waddizzle!

[Waddizzle]

Manually moving AF points around is for DSLRs. The AF system and n MILC bodies can move the AF point to track your subject faster than you ever will. 

[Tronhard]

I use BBF with single point autofocus set to centre and eye/face tracking (for living creatures).  Removing the focus from the shutter button does not necessarily stop the shutter button from doing metering - it depends on what you select.  However, I prefer to use Centre Point Exposure for MY purposes, as I shoot wildlife in a lot of highly dappled situations, so I need that level of precision, and one cannot assume that the place that has a mid-reflectance is the point one is focusing on.  Thus I have the * button set to AE ON-OFF.
Red Panda @10m: R5, 600mm, f/9, 1/500sec, ISO-6400
In this example, I was literally shooting between the leaves and branches and the panda was moving about.
I don't use the joystick to move the focus point around, as Bill (Waddizzle) said, it's too slow and if I did I would use my thumb on the joystick rather than move my finger off the shutter button - I use my thumb to lock both focus and exposure.  If you are using eye tracking, then once the focus is locked it should follow the subject.  That said, focus can get fooled, certainly by dense obstructions, so (again using my thumb) I can re-centre the focus point using the OK button, or if you prefer pressing in the joystick button.

So, in order of events: I choose a point that has the right reflectance and place it into the centre of my EVF, and press the * button to lock exposure
Locate the eye, or other strategic part and centre on that, press the AF-ON button. Depending on the mode I am working in (may not be face/eye tracking) I may be using Servo focus, and holding down the AF-ON will track that point for a dynamically moving subject, as opposed to a simple tap that holds that focus distance for a static one. I then recompose and take the shot using the shutter button.
I have different scenarios assigned to the C1... C3 buttons for tracking or otherwise.

Once you get the hang of it, it's extremely fast and the only phalange that has to move around is the thumb, leaving my finger always poised above the shutter button ready to take the shot.  It works for me... FWIW.

[musicmaiden]

Thank you, Trevor, for this detailed description of your set-up and how you use it in the field.  And that cute pic!!! Yes, the joystick is too slow for my bird photography, but for  taking pics of insects on flowers, for example, in One-Shot Mode and using manual focus ( and using magnifying glass), moving the joystick to my focal point with my thumb is what I like.  However, after reading all the comments and replies, I may not stuff everything in one setting but use the Custom Modes to separate the bird photography from the insects/flowers.  I will also give your centre-weight metering a try when looking for birds in the woods! Thanks for the tips! Really enjoying your panda!