D610+Tamron 24-70 = Auto focus problem+Number of focus point 11 not responding

[blacksheep]

Hi,
I recently have invested in buying D610 with a combination of Tamron 24-70 lens, and have been suffering from figuring out how to use Auto-focus.
I was used to use a prime lens 35mm on D90 before, and auto focusing was very simple.
Now I'm struggling with too many focus points and have been trying to just have one central focus point just like I used to.

By reading the instruction manual, it does not seem that is possible.
So at least I wanted to reduce the number of auto focus points from 39 to 11 from the menu, and noticed that it would not be reflected on this lens. I just see the same number of hunting points through the viewfinder.

Is this a lens fault or camera fault, or just a way it is when using this combination of this lens and the body?

Anybody had a same experience as me?

Many thanks in advance for your input..

[Polar01]

Try holding the AF/M button on the front of the camera lower left side that you flip to go from manual to auto focus. Once the button is pushed in and held, turn one of the control wheels looking at the top screen and select centre focus. You can also change the number of focus points by going into the I believe shooting menu and setting the number of focus point.

Cheers: Allan

[PhotomanJohn]

Start on page 100 of your camera manual. Set the camera to single point focus and then select the center focus point.

John

[dje]

Yes I wouldn't say that this section of the manual is terribly well written but as Allan says, push the AF/M button in and rotate the front wheel (just below the shutter button) to select single point focus. The rear wheel is used to select between AF-S, AF-A and AF-C.

Dave

[Dave Humphries]

Hi Mariko,

As Alan and Dave have already said, the quickest way is to hold down the button in the centre of the AF/M control with the middle finger of your left hand, while rotating the front wheel with your right index finger and observe the top LCD display.

One aspect of this I just noticed is that the single point option is denoted by "S", which could easily be confused for a "5" (number five) - and I wondered whether this is what is confusing you.

If I clockwise rotate the front wheel (on my D7100), the options I get are; Auto, S, d 9, d21, d51 and 3d (then back to Auto again), your numbers may differ (e.g. 39 and 11), but I hope you get the idea.

It is possible though.

Cheers, Dave

[blacksheep]

Oh I didn't get any notification that I was already getting replies here. Thank you!

I've already tried pressing AF mode bottom to change to AF-S.

I tested this by selecting the 11 point AF mode and enabling the Single AF Area mode on the D610 and then looked through the viewfinder to count the total number of positions I have to choose from.
It is never max 11. Way more.

According to the manual page 223, I should be unable to select anywhere else as an AF point other than the positioned detailed in the 11 point diagram in the screenshot I attach here.

[blacksheep]

[dje]

Hi Mariko

You will only get notified if you subscribe to the thread, even when you create it.

As for your latest post, I'm not sure that I understand your problem. If you have Autofocus custom setting a6 set to 39 points, you will be able to select any one of these points as the single focus point. You do this with the left and right cursor keys on the multi selector control (the one with OK in the middle) and you should be watching the rear screen to see this happen. The lever on this multi selector must be set to the dot position, not L for lock.

If you have a6 set to 11 points, only 11 of the points will be available for selection in the same way. I think this is a quick select mode.

In each case, you will see one of the diagrams in your screenshot above on the rear screen.

Dave

[blacksheep]

Hello Dave,

Yes, you are right. That is how it should be. However, when I have a6 set to 11 points, I don't see the diagram of AF11 in the above table. That's not what I see through view finder. I see only one central point selected.

I discovered that I could move that one central point to up, down, right and left - there are 11 points all together.
Great, but this works differently from AF39. With AF39, camera just auto-hunts the subject within the available 39 points.
With AF11, you have to move the focus point within the available 11 points.
Is there anyway to activate all the 11 points?

[dje]

Hi Mariko

The system works differently depending whether you are in AF-S mode or AF-C mode.

In AF-S mode, if you press and hold the AF button, the front wheel gives you a choice of single or auto. After selecting Auto, I'm not sure if the 39/11 selection affects the auto mode or not but I don't it does. I think any of the 39 points will be selected automatically.

In AF-C mode, the front wheel gives several selectiions

single point
dynamic 9 point
dynamic 21 point
dynamic 39 point
3D
Auto

In this AF-C mode, I think single point and Auto behave the same way as for AF-S. However the dynamic point selections give you a choice of restricting the number of points used in tracking and also the 39/11 selection restricts the available points for initial point selection as well. But this is a tracking system and the main focus point will be the one selected and the others are only used if the subject shifts off the main focus point whilst tracking.

I haven't done much with dynamic tracking I'm afraid so I can't really explain that very much.

This article here might help.

Dave

[blacksheep]

In the article, it says:

"If you set to 11 AF points your selection will be limited to those 11 AF points, but the additional surrounding AF points will still be active to be used by the camera in the AF-Area Modes and in subject tracking, so the camera is still taking advantage of all the AF points of the autofocus system."

I'm getting a bit confused now.... let me clear up my head again.

In AF11 mode, when I set it to...:

1. Auto Area AF + Single-Point AF = AF11 is not usable. Auto focus just tracks among 39 spots. All available.
2. AF-S (Single-servo AF) + Single-Point AF = I see only one square in the centre thru view finder. I have to move that manually by the multiselector. Then I see that one square can only move within 11 available points.
3. AF-C (Continuous-servo AF) + d9 = Again, there's only one square I see. I can move it, but not within 9 points. It moves within 11 points! Same goes for AF-C + d21, AF-C + d39. Basically I don't see any difference in its performance among d9, d21 and d39 now. It just hunts among all the available points I choose in the menu (AF11/AF39). This is very wired. If I hold down the AF mode button, d9/d21/d39 shows those numbers of points each. But when I actually try to take a picture, the view finder only shows one square. Then I half-press the shutter button, which moves that one square within - again, the available points I chose in the menu (AF11/AF39).

Initially I was puzzled how AF11 works, but now I'm even more puzzeld how d9, d21 and d39 works...

[Dave Humphries]

Initially I was puzzled how AF11 works, but now I'm even more puzzled how d9, d21 and d39 works...

I think I do understand this aspect Blake, so let me try to explain - although a picture might have saved a thousand words
(but I don't have one)

The basic choice of (what I'll call) 'primary' focus points to use are either 11 or 39, for D610 (11 or 51 for my D7100) - basically this just means 'some' or 'all'.

Consider we're in 11 point mode.

Consider we're using the "dynamic" option "d9", you are still 'aiming' using ONE of the 11 possible 'primary' focus points (and you can select which ONE with the pad), but the AF system is actually using a grid of 3 x 3 (hence "d9"); another 8 points immediately surrounding the 'primary' ONE. I'll call these 'secondary' points, they help track the subject if it moves relative to the ONE focus point.

Now; these 'secondary' points can be focus points that you're nominally not using, they will be the ones around whichever ONE of the 11 points you have chosen with the pad.
If the chosen primary point is near the edge of the entire focus area, some of the 'secondary' points are not available.

Get the basic idea?

As has been noticed; the 'secondary' points will not show up in the Nikon EXIF view (or V/F review option) which shows the chosen ONE point.


In "d21" mode; there are 3 more 'secondary' points on each side of the 3 x 3 grid, making a total of 20 'secondary' points around the 'primary' ONE you select, giving a wider area to assist focus tracking.

In "d39" mode, it just means all points are 'secondary' points (except the the ONE you chose).

I guess theoretically the 'secondary' points will not acquire focus (if no AF lock), but will retain it if the 'primary' point has already achieved AF lock and the subject subsequently moves off that, but remains within the active area of 'secondary' points.


I have a feeling that if you find a small defined subject which ought to be about the same size as a single focus point, and view this against a completely bland, featureless background - say the moon viewed at 50mm - and experiment with all the different settings and slowly move the camera while acquiring and attempting to retain focus as you aim-off, you'll eventually see a difference in the way the AF behaves for all the different options (d9, d21, d39 and 11/39 selection).

However, I suspect that in everyday use - against complex backgrounds, the differences are so subtle as to be "puzzling"


I find that for wildlife shooting, I rarely need the precision offered by allowing the 'primary' point to be selected from all 39 (or 51) points - it just gives too much scrolling with the pad to get it from one place to another in the viewfinder.

I hope that helps, Dave

[dje]

Mariko I think Dave has provided a good summary of how the dynamic area modes work. The following overall summary of the various AF options may also help.

• Focus point selection can be either manual or automatic.
• For auto selection, all 39 points are available for use by the camera
• For manual selection, the number of points available for selection is 39 or 11, depending on the choice in custom setting a6.
• Manual selection can be used for single servo shooting or for continuous servo shooting, including dynamic area modes. In a dynamic area mode, focus points surrounding the point manually selected are used for tracking if the subject moves away from the manually selected point. The number of surrounding points used can be 9, 21 or 39.

Dave

[Dave Humphries]

In a dynamic area mode, focus points surrounding the point manually selected are used for tracking if the subject moves away from the manually selected point. The number of surrounding points used can be 9, 21 or 39.

Yeah that's about what I meant to say (in far fewer words)

[dje]

Yeah that's about what I meant to say (in far fewer words)

Actually I should have said "the number of surrounding points that can be used is 8,20 or 38 !!

[Dave Humphries]

Actually I should have said "the number of surrounding points that can be used is 8,20 or 38 !!

Yeah, I know Dave - but who's counting?

... and it wouldn't surprise me if the manual was similarly worded in some places