Switching back to AF on the shutter?

[afx]

Hi gang,
for ages, I have been using AF-C with AF just under my thumb instead of the shutter.

I recently acquired a D850 and was discussing AF with a PJ friend of mine who has been using the D850 for quite a while already.
He switched from AF-ON to having shutter activated AF and uses the AF-ON button for AF Lock if needed. He said he has less of a cramped thumb this way and is faster on the joystick to switch AF points.

Been thinking about this and I wonder why use a finger and thumb constantly instead of using only a finger and occasionally the thumb.

I'll try that for a while, but I wonder whether I am missing something.

cheers
afx

[David H. Hartman]

The use of the AF-ON button is quite simple: press to focus, release to lock. This is for me very much like the logic and reflexes of manual focus cameras like the F2, F3, FM2n and FE2. It's quick and natural. There is no need to changes settings for manual focus lenses unless non-CPU data is used. If an AF lens is installed I use the AF-ON button. If a manual focus lens is installed I use the focus ring. This is a reflex. I don’t think about what kind of lens is on the camera. The fingers know.

I have no problem with switching from the focus joystick to the AF-ON button and vice versa. They are very close together. I have no problem with cramps in my thumb.

For AF-C (continuous servo) I hold the AF-ON button down and track my subject. There is no need to ever switch my camera from AF-C to AF-S and vice versa.

What matters here is do what is most natural, most comfortable to you. Try both methods and use what you prefer.

Best,

Dave

[afx]

When using the AF-ON button to focus and release to lock while the camera is set to AF-C (continuous servo) there is no need to switch between AF-C and AF-S (single servo). For AF-C just hold down the AF-ON button and track your subject.

This is what I have been doing for the last 15 years...
But as I rarely need locked focus but mostly continuous (moving animals) it sounds more economic to do it the other way round, only explicitly lock AF instead of constantly using a second button for focussing.

Time will tell
afx

[David H. Hartman]

But as I rarely need locked focus but mostly continuous (moving animals) it sounds more economic to do it the other way round, only explicitly lock AF instead of constantly using a second button for focussing.

To clarify, just in case, I never use any button on my cameras to lock the focus. I think I've been using AF as described above since my F5. I don't believe my F4s had an AF-ON button and that the Canon counterpart at the time did.

Dave

[David H. Hartman]

The Joystick center button can be set to be an additional AF-ON button. For example it can be set to AF-area mode + AF-ON, Dynamic-area AF (9 points) using f1 Custom control assignment. There many other options not just Dynamic-area (xx-points) so it's best to have a look to see if something there looks useful.

Pressing the joystick center button without accidentally moving the AF point selected may take some practice.

Dave

---

On the general topic of AF: a7 Store by orientation might, be interesting. I bird sit a lot for a friend's cockatoo. Depending on weather she is walking or sitting she is either long or tall. Using a7 the camera remembers where I last set the focus point for a horizontal or vertical framing. The object is to get the focus point on the bird's eye as fast as possible. With the AF point on the bird's eye I wait for attractive light on the bird's head and a catch light in her eye. No catch light the eye is dead like the eye of a shark. The shot will be discarded.

[Matthew Currie]

To clarify, just in case, I never use any button on my cameras to lock the focus. I think I've been using AF as described above since my F5. I don't believe my F4s had an AF-ON button and that the Canon counterpart at the time did.

Dave

Definitely no back button or AF-On equivalent on an F4.

[Erik Lund]

I have kept on using AF on the Shutter button all along,,,
Works perfectly 
Yes it keeps the thumb free to work the rest of the rear buttons, especially to move focus point around for street, action and PJ style shooting.

[Bent Hjarbo]

I have kept on using AF on the Shutter button all along,,,
Works perfectly 
Yes it keeps the thumb free to work the rest of the rear buttons, especially to move focus point around for street, action and PJ style shooting.

Me too

[Ilkka Nissilä]

If I recall correctly, I switched to AF-ON use when the D70 gave me a hard time in producing consistent focusing and found that it was easier for me to work by explicitly telling the camera when it is to focus and when not, independently of the shutter button. I also started using my other cameras in this way at the same time, although they didn't have the D70's focus problems. What I like about AF-ON is that if I want to do a spot meter reading of a specific area to set manual exposure, I don't want to camera to change the focus. When I put the camera on a tripod for a photograph of a static scene, I may set focus once and then I may do other things and I certainly don't want the camera to refocus every time I take a picture, it might do something wrong and mess up my shot. Yes, I can switch to manual focus but by assigning AF-ON to AF, and release+focus mode with AF-C, I can choose freely when to activate autofocus and when to focus manually without changing any switches.

Unfortunately things have gotten more complicated with all these focus-area modes and so that kind of destroys my principle that the camera should operate always the same way, without modes. These focus-area modes are sometimes needed for photographing moving subjects so I go along with that, even though it means sometimes the camera isn't in the right mode for the situation.

Accessing the focus point selector is easier when the thumb is free if you want to change the focus area during an active situation but I accept this as a compromise to get the other things that I like about AF-ON. I try to anticipate the situation and choose the right focus-area mode in advance so that I don't have to change the focus point or area during a situation. This doesn't always work but fortunately with the D6 I've managed to shoot hours of action without having to touch the focus-point selector (custom group-area with face-priority allows the camera to find the closest face within my selected area and this is typically where I have the face in focus in figure-skating, and it even switches automatically between two sets of settings between horizontal and vertical orientations). So only during one element (death spiral) did I have to move the group-area from the top of the frame to the bottom to get the shots, while for the rest of the time I could avoid touching any of the focus point or area settings.

[Dogman]

Since film days with AF, I've used the AF ON buttons.  It's a natural for me.  But I only use the center AF sensor for normal shooting so I don't need to chase other buttons around on the camera back.  On rare occasions I just let the camera pick the sensor for focusing and I still use AF ON. 

How you manipulate your camera is whatever works best for you.  Nice to have choices.

[David H. Hartman]

...custom group-area with face-priority...

....switches automatically between two sets of settings between horizontal and vertical orientations...

Ilkka,

After referring to my D850 manual(s) and the D6 manual(s) it appears that "Custom group area" is a feature of the D6 but not D850.

In single point AF I have set my D850 to switch automatically to the last point selected in horizontal or vertical orientation. When I press the AF Sub-selector (joy stick, center switch) my D850 switches from single point AF to Dynamic-area AF (9 points).

Face detection for the D850 appears to be limited to AF-Area Mode, 3D Tracking.

I'm trying to follow (understand) your use a AF as your understanding and use of AF is far more sophisticated compared to mine.

Dave

Just in case someone is curious about what the hell I'm setting on my D850...

a7, Store by orientation, Focus point
f1, Custom controls assignment, Sub-selector, Focus point selection
f1, Custom controls assignment, Sub-selector center, AF area mode + AF-ON, Dynamic area AF (9 Points)

I'm trying to gain sophistication in my use of new features of my D850. 

[afx]

What I like about AF-ON is that if I want to do a spot meter reading of a specific area to set manual exposure, I don't want the camera to change the focus. When I put the camera on a tripod for a photograph of a static scene, I may set focus once and then I may do other things and I certainly don't want the camera to refocus every time I take a picture, it might do something wrong and mess up my shot.

Thanks for the reminder.  This would be the thing to keep the AF on AF-ON instead of the shutter. After all, I do not only shoot action. 
And switching the AF activation mode on every shoot would be a nightmare in terms of muscle memory.

The other hint from David about the focus point orientation switch seems to be a good idea.

So now I can focus on finding the right AF setting for playing dogs...

thx
afx

[Jack Dahlgren]

I’m not good with AF and hate to have to move the focus point around. Usually I just point the camera at what I want in focus, mash the AF on button briefly, then recompose. I can see how others might choose a different approach but this works for me.

[David H. Hartman]

The other hint from David about the focus point orientation switch seems to be a good idea.

I've found it (Store by orientation, Focus point) most helpful when photographing my friend's cockatoo who is either long or tall in a moment. I only recently learned of this option. Also Ilkka is using the same feature on his D6 as I understand his post above.

Dave

[Erik Lund]

I've found it (Store by orientation, Focus point) most helpful when photographing my friend's cockatoo who is either long or tall in a moment. I only recently learned of this option. Also Ilkka is using the same feature on his D6 as I understand his post above.

Dave

On the first cameras this function was implemented on it was too slow to react to movement. I lost quite a few frames back then.Might be better in the latest cameras,,, but just the thought of missing out due to lag is enough to keep me away from using it.