EOS R5 Mark II - Custom AF Menu Question

[bkryzer]

Hello Canon Community

I am relatively new to Canon and have some questions regarding the AF menu.  I have my camera setup to do double back button focusing (one for setup of one-shot focusing primarily for landscapes and one for action sports shooting).  For action shooting I have the (*) button customized for people subject detection with eye detection enabled along with the servo characteristics.  There is one option that I don't understand.  The first menu item (which I do not enable) is for AF Start Position.  I cannot for the life of me find anything on this in the user manual.  I have a photo of it below along with the options if it is selection (Manually Selected AF point vs Registered AF point).  Would anyone be able to shed some light on this and what the two options enable?

Thanks!

Bryce

[p4pictures]

The first option would mean that the camera overrides the current focus point position. The options are for a manually set position or the registered AF point position. This setting allows you to force the AF point to a specific part of the frame when you press the back button. If you are using whole area AF then this setting is irrelevant. 

[pcfam]

---

@p4pictures wrote:

The options are for a manually set position or the registered AF point position.

---

How do you manually set the position?  When I try this, the position seems to be locked at the center, and I don't see any way to change it.

The alternative seems to be to register my desired points, but then I end up with a blinking gray rectangle at all times.  Is there any way to turn off the blinking rectangle?

[p4pictures]

The manually selected position is actually the "current" position of the AF point. If that current position is in the centre, then it will be the centre. If the current manually selected position is the top left corner of the frame then this is the position. In effect it's saying use the current position - it does seem a little bit superfluous, but might be because other buttons were used to force to a registered AF position and this would put it back. 

The second option for registered AF points is indeed correct that you need to register the AF point, and then you'll have the grey blinking frame indicating the position of the registered AF points. There is no way to switch that grey blinking frame off.

[pcfam]

---

@p4pictures wrote:

The manually selected position is actually the "current" position of the AF point. If that current position is in the centre, then it will be the centre. If the current manually selected position is the top left corner of the frame then this is the position. In effect it's saying use the current position...

---

Thank you, that's what I was wondering, but it's not using the current position, which I have at the upper 1/3 line; it's resetting to center, whether or not I have a checkmark next to set "AF Start Point" to the selected point.

To elaborate:

1. If I'm in a point focus mode (1-point, expanded, etc.) and I press my BBF button, the focus point will stay at the current point (as expected).
2. But if I'm in whole area AF and I press my BBF button, the focus point jumps to center, not to the point-focus's selected point (whether or not Start AF Point is checked).
3. If I switch back to point focus, the selected point is still where I left it (top 1/3).

This seems like a bug to me, since there's persistent notion of selected focus point (even if I'm temporarily in some other zone focus), but the "Start AF Point" function ignores it unless I was already in a point focus mode.  And that seems to make it truly superfluous!

[p4pictures]

When you use Whole Area AF there is no "start position" selectable. For the other AF areas there is an initial position. It is possible that the camera engineers "coded" in to jump to the centre if whole area AF is selected and the back button is pressed and set to jump to the manually selected AF point. 

[pcfam]

I imagine that's how they coded it, but even if it's intentional, I think it's unlikely to be what people want.  If a user wants it to "remain" at the center, they can just uncheck the box.  But as it is now, there's no way to make it use the currently selected start position.