Understanding AF Handoff - Z8

[Don_Logan]

Hello,

I have watched Steves videos - read that part of his book and have watched Henry Hudsons video on this matter AND have put it to use......but I am a bit confused.....

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My button settings:

AF-C

AF-ON: AF-ON

Fn1: AF-area mode + AF-ON (Wide area AF (L) )

Fn2: AF-area mode + AF-ON (3D)

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Logic:

I use the AF-ON button as AF-ON with AFC-C just for point and shoot with static objects when walking around looking for things to shoot (buildings, just things that are static) I am guessing I should de in AF-S for this? But I see no point as it locks onto a building or another "thing" right away. So am I good there? If I was going into a shoot knowing there would be zero moving objects I would change it. I am also new to this, so I am just more comfortable leaving it there for fear of forgetting to change it to AF-C for people, animals etc.

My brain is not working really well without Fn1 and Fn2 setup AF-ON. I know Steve says to just set those areas without it and use the back button AF-ON ( I think Henry too) but my brain just wants to hit the Fn1/Fn2button and have it do all the work - without having to press back button AF-ON to focus......Am I doomed if I do not force myself to do it the other way?


Getting to the point:

Okay, so I see a dog, hit Fn1 I get eye lock within the large box WHILE STILL HOLDING Fn1 I press Fn2 to switch to 3D and I get nothing no "handoff" (my brain says the large box should disappear and the small 3D box should overtake the small target box - signaling I can release Fn1). What actually happens: I hold Fn1 and press Fn2 (again while still holding Fn1)- nothing happens so I release Fn1 and it disengages "eye lock" I then press Fn2 and it engages the eye with 3D. HOWEVER, there is a fleeting moment where there is no AF lock on the subject.

My question is, is that normal? Is that the handoff? Is it because the focal length and everything else is so close to where it was, the brief second you have to lose focus to switch AF type that camera's chip (wizardry) can * usually* just grab the eye again with 3D?

OR

Do I have the idea of all this wrong? Again, I have tried my best to get this or understand the concept before writing this message.


Thank you for all the help!

 

[DRwyoming]

Thank you for all the help!

A lot in your post to untangle but here's a bit to think about:

- The AF-S vs AF-C decision is pretty easy, if you're using BBAF and not using the shutter release to activate the AF system then there's not a lot of reason to use AF-S at all. AF-S does offer the very small Pinpoint AF Area that some folks like to use which unfortunately isn't available when shooting in AF-C mode. It also offers the option of an audible focus lock beep that some folks like but probably the biggest reason many folks use AF-S mode is to focus and recompose for static subjects. When shooting with BBAF that third item really isn't necessary as you can just focus on the desired subject and then release the back button, recompose and shoot without hitting the AF-ON button and you achieve the same thing. The Pinpoint AF area mode is sometimes handy for very precise focus point but mostly for static (not living) subjects. Most live subjects twitch at least a bit so staying in AF-C mode helps the focus follow tiny movements that we see with a lot of wildlife subjects and the Pinpoint AF Area isn't as useful as it once was with the advances in Subject and Eye detection. Personally as a BBAF shooter with my Z8 and Z9 I only shoot in AF-C mode except for some special case Manual Focus like astrophotography and some landscape work.

- You can't really handoff from one Fn button to another Fn button. Handoff works when you activate AF (in a mode that supports Subject Detection) via one of the main controls (AF-ON or shutter release half press) and keep holding that as you press your alternative focus area button. Hitting one button and then releasing it to hit another AF Area button isn't really a seamless handoff as you had to release the first area before activating the second area. And in your case with the starting AF Area Mode set to Single Point, as you release one Fn button even for a fraction of a second before enabling the other Fn button the camera drops back to the starting area (Single Point) which does not support Subject Detection. That won't be a seamless Subject Detection handoff as the new mode has to start from scratch in terms of Subject Detection.

- What a lot of us are doing is setting the default camera AF area to what we think the subject requires or at least has a high probability of achieving initial focus. That might be Wide Area Small, Wide Area Large, one of the custom C1, C2 areas or something else depending on the subject. Then we have one or more buttons set to alternative AF Areas that usually are wider ranging across the field of view like 3D or Auto. So we achieve initial focus with a relatively small area that has the best bet of grabbing decent focus and hopefully allowing Subject Detection to detect the body, head or eye. Once we see the small green box indicating Subject Detection we then might just start shooting or we might select one of our wider modes to allow the Subject Detection to follow the body, head or eye as we recompose or the subject moves in the frame.

- Doing it this way supports seamless handover from one Subject Detect supporting mode (like those listed above) to a wider area Subject Detect supporting mode like 3D or Auto. You don't really get full active handover if you start in an AF Area mode that doesn't support Subject Detection (like Single Point or one of the Dynamic Area modes) to a wide mode that does support Subject Detection. IOW, for handover you really want Subject Detection to kick in prior to handing over to the alternate mode and we know that has happened when the smaller green boxes grab the body, the head or the eye.

- One nifty trick for keeping what's basically a Single Point area that also supports Subject Detection is to set up a custom C1 or C2 mode as a 1x1 box (same size as Single Point) but the C1 and C2 modes support Subject Detection so they also support seamless handover. It can be a good choice for the default camera AF Area mode as you can use it just like Single Point for static and non-living subjects but also use it to acquire initial focus for live subjects that aren't moving around too much and then handover once Subject Detection kicks in if desired.

- The choice of starting AF Area Mode is usually achieved either by using the AF Mode Selector (on the front near the lens release lever) and dials or by programming a custom control button for either that same function (often the video button as it doesn't really have a job when shooting stills and is easy to reach with your eye to the viewfinder) or to set up the new AF Area Cycle function where hitting the programmed button multiple times lets you cycle through a list of AF Area Mode options to use as your starting AF Area Mode.

Hope that all makes sense,
-Dave

 

[Don_Logan]

Thank you for the reply! Yes, lots to unpack with my post, but its all tangled in my head too - I did my best haha.


Okay that makes sense for AF-C / AF-S......Glad to know I really do not have to mess with that for the most part.


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Okay, I think I got it! I just tested what you said on my dog from paragraph 2.

New settings:

-Default camera focus: Wide-L (W/O AF) ........(it was Single Point AF)

-BBAF....same as before.

-Fn1: (Single Point AF - AF ON)

-Fn2: 3D (W/O AF)



^ the above makes sense to me. Without pressing BBAF within the large red box, the grey box pops up when it detects an moving object (dog in this case), and once I get it I hit the BBAF it turns green and the better job I am at getting the frame right, it moves from body to head to eye....and once it grabs the eye I hit Fn2 for the smooth handoff I was expecting to 3D....which then leave me to be less precise in my movement as I now have the entire frame. Got it

^^ Getting it like this from my initial post left me not knowing now what to do with Fn1 so I made it what I did for static subjects. Fn1 = focus in and lock on without the need for BBAF right on a 1X1.

Thank you. I cannot tell you now much that helped I had tried for hours to get it!!!

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In regard to the nifty trick - I saw the video Steve just posted on that. If I understood his video correctly, was that not to replace the 3D though? I was watching while flying yesterday and was distracted. I need to rewatch it.

 

[DRwyoming]

In regard to the nifty trick - I saw the video Steve just posted on that. If I understood his video correctly, was that not to replace the 3D though? I was watching while flying yesterday and was distracted. I need to rewatch it.

If you're referring to setting up a custom C1/C2 as a 1x1 area it's really not to replace 3D. It's really a feature enhanced version of Single Point AF Area in that it supports subject detection. IOW, it gives you a very precise focus area to establish focus which you can then just use for shooting or once it establishes subject detection can hand off to a wider area that also supports subject detection if desired or needed for the situation.

Your controls sound good and the ability to quickly switch to Single Point is one way to disable Subject Detection if for some reason it isn't working the way you'd like or if you just don't need it (e.g. landscape, some product/architecture work, some macro work, etc.). But also remember you don't necessarily have to assign both the Fn buttons to AF Area modes, you could use that for a variety of other features like DoF preview, spot metering or many other things you might sometimes want on the fly. Nothing wrong with what you're doing but from your post it sounds like you feel it's necessary to use both of those buttons for AF related reasons.

 

[Don_Logan]

Okay got it.I will mess around with that here soon. For now will run the above until I get a better handle on things.

Good to hear. Ya, the idea of just hitting Fn1 and have it single point AND focus for a quick point and shoot sounds nice. I am coming from a phone as a camera, so the idea of just having a quick/simple read: something familiar - is nice to have. I am sure as I get use to things the button set will evolve.

And yes, there is all the other stuff too. TBH, I have minimal clue what some of it means or does. I will need to just get out there and shoot 300 to 500 photos every weekend for the next few months and sprinkle questions in here about further features during that time. The learning curve is extremely steep, and I do not want to bite off more than I can chew with all this.