D700 Focus issues? Help please!

[wenrob]

First let me preface this by saying I know there's a learning curve but this seems like a really odd problem and I'm hoping you guys can help me diagnose it. And forgive the color/comp, these were just quick tests.
I have always used Af-S Dynamic area on the D90 and in the last year and half have been toggling focus. I am pretty good nailing my focus even at wide open apps with multiple people in the pic. It's the type of photography I'm into and so I practice A LOT. What I'm saying is I'm pretty confident in my focus abilities. That said this could totally be me.
At first I thought I might have a DOP issue since I know full frame has a shallower DOP. But the weird thing is the camera seems to focus one side or the other and tends to prefer a certain Sassy Red Head. It seems for DOP it should fall off on both sides right?

My focus settings here were AF-S Dynamic 51 points. Shot at f/2.8 which at first made me think it was a DOP thing. See how sharp she is and how his eyes and bangs are a smidge fuzzy?

So I decided to test things out and took these at f/4.5
Purposely aimed at DH's arm in the center. DS is sharp but DH is not.

Focus aimed right between them, DH sharp, DS soft:

Again center on DH, the camera chose (?) DD:

These are f/3.5 both focused on DS's right eye. Moved the switch to single only thinking that was the problem. Again the focus hits DD:

Succeeded here, focus spot on DS's right eye again:

So what am I doing wrong? Or am I? It does this with both lenses. I'm really hoping this is user error but I just can't figure it out. Like I said I'm pretty steady I don't think I'm shifting in anyway and it's not a blur issue but a weird fall off issue?

 

[GrillMouster]

As you said, depth of field is more shallow on a full-frame camera than it is on a crop-sensor camera at the same aperture setting. In nearly all of the images you posted the subjects are not on the exact same focal plane. One person's eyes are slightly closer to the camera than the other person's eyes (I mention the eyes, because in portraiture that's what you want in critical focus, so focus on them). At f/2.8, standing a few feet away from the subjects you're talking about just an inch or two of depth of field.

 

[wenrob]

As you said, depth of field is more shallow on a full-frame camera than it is on a crop-sensor camera at the same aperture setting. In nearly all of the images you posted the subjects are not on the exact same focal plane. One person's eyes are slightly closer to the camera than the other person's eyes (I mention the eyes, because in portraiture that's what you want in critical focus, so focus on them). At f/2.8, standing a few feet away from the subjects you're talking about just an inch or two of depth of field.

Doing some reading and it seems I'm going to have to relearn my DOP all over again. I really thought f/4.5 would be more then sufficient. I'll close it down some more and retry. I think I just had a panic moment, lol. Just seems weird one side or the other and the camera clearly favors DD.

 

[GrillMouster]

Oh, and not all things that fall within the depth of field, or range of acceptable focus, is going to be equally sharp. The area you focus on will be critically sharp and sharpness will gradually drop off in front and in back of that focal point. Generally, depth of field extends 1/3 in front of the point and 2/3 behind. So, if you have two subjects with eyes close together, you'll get better chances of having them both fall within the depth of field if you focus on the eyes of the one closer than if you focus on the eyes of the further. If you're shooting a group arranged in four rows, you'd want to focus on the second row of people (and ensure you're aperture is stopped down enough).

 

[wenrob]

Oh, and not all things that fall within the depth of field, or range of acceptable focus, is going to be equally sharp. The area you focus on will be critically sharp and sharpness will gradually drop off in front and in back of that focal point. Generally, depth of field extends 1/3 in front of the point and 2/3 behind. So, if you have two subjects with eyes close together, you'll get better chances of having them both fall within the depth of field if you focus on the eyes of the one closer than if you focus on the eyes of the further. If you're shooting a group arranged in four rows, you'd want to focus on the second row of people (and ensure you're aperture is stopped down enough).

Yeah I just didn't expect it would fall off to one side but looking at them DD does seem to be prominent in most of them.

 

[GrillMouster]

Doing some reading and it seems I'm going to have to relearn my DOP all over again. I really thought f/4.5 would be more then sufficient. I'll close it down some more and retry. I think I just had a panic moment, lol. Just seems weird one side or the other and the camera clearly favors DD.

Hold on; you keep saying that the AF is "favoring" DD, so you're letting the camera determine where it focuses? You're not tracking birds or fast-moving subjects. With reasonably static subjects, just use single-point AF, no tracking. You can move the focus point to where you want it. If you're using the center focus point and recomposing it could be trouble at really wide apertures.

 

[gruZ]

Have you tried an "official" focus test? I've used this one before:

http://focustestchart.com/chart.html

and it's worked very well. If you take out all the other variables you should be able to tell whether or not the camera has a problem.

 

[wenrob]

Hold on; you keep saying that the AF is "favoring" DD, so you're letting the camera determine where it focuses? You're not tracking birds or fast-moving subjects. With reasonably static subjects, just use single-point AF, no tracking. You can move the focus point to where you want it. If you're using the center focus point and recomposing it could be trouble at really wide apertures.

No, no, I'm moving the focus point where I want it, I don't recompose. I haven't let the camera choose in years. This is why I got concerned. In these pics I put the focus on DS more and it still focuses on her. I'm not moving, they're not moving. Her hair, eyes etc are tack sharp and him it falls off even though the focus was aimed more towards him.

eta: It doesn't seem to be falling off like normal DOP field to me which is why I posted. It seems like the camera is "choosing" even though I set it up for ME to choose.

 

[GrillMouster]

In the custom setting menu I use 51-point 3D (not 51, or 21, 9, or whatever else there is). The 3D tracking option is the only one that will actually show you in the viewfinder where the active AF sensor is moving/tracking in the frame. The other options will use the surrounding sensor points to track, but will not show you which of the surrounding points are active. I think the visual 3D tracking only works if your AF mode is AF-C and the sensor selector on the back is set to full auto (big white box) or the center setting. With a single flip of a switch and without moving the camera from my eye I can go from 3D tracking to single-sensor AF, my two preferred modes.

Additionally, I've moved my AF function away from the shutter release button to the button on the back of the camera. This way, I can push the back button with my thumb to get focus. Once it's achieved focus, simply letting go of the button essentially locks the focus in place (so it won't stray or track). When I press the shutter release button it WON'T try to AF again. I've been working this way for years now and I love the control it gives me over both focus and exposure.

Correction: The 51-point 3D tracking does not work with the back AF mode switch in the top (full auto) mode. It only works in the center (crosshair) mode with AF-C.

 

[GrillMouster]

In the camera you can change the playback settings to show which focus sensor it used when the picture was taken.

 

[wenrob]

When I tried the 3D it seemed like it just jumped all over the place and I couldn't half press fast enough to lock it. Can you use the AF-On button to BBF? I'm left eyed so the AF-L lock is not in a good spot for me. Also in AF-C I don't get the beep which I've become so dependent on.

If my kids will let me I'm going to close it down some more and see if that helps. Then work my way down again. I guess I should have more patience I've only owned the camera for a couple of days and not had alot of shooting time yet.

 

[wenrob]

In the camera you can change the playback settings to show which focus sensor it used when the picture was taken.

Yeah, I have that set which is why I'm so confused on where the focus fell when it shows me where it was aimed, kwim?

 

[GrillMouster]

When I tried the 3D it seemed like it just jumped all over the place and I couldn't half press fast enough to lock it. Can you use the AF-On button to BBF? I'm left eyed so the AF-L lock is not in a good spot for me. Also in AF-C I don't get the beep which I've become so dependent on.

If my kids will let me I'm going to close it down some more and see if that helps. Then work my way down again. I guess I should have more patience I've only owned the camera for a couple of days and not had alot of shooting time yet.

3D can jump all over if the scene is dark, there's not much contrast, and/or there's something touching or really close to your subject that resembles the subject in tone or contrast. For example, two kids touching heads...It's very easy for tracking to jump around. That's why I jump to single-sensor AF. Tracking isn't necessary for static subjects; it can ruin things, like vibration reduction can ruin a tripod-shot image.

I shoot left-eyed, too, and I don't have a problem using the back AF button. I don't know if AF-C disables the audible focus-lock sound, as I immediately mute the camera as soon as I buy it. Besides, the viewfinder has a little dot that appears when focus is locked and the AF sensor in the viewfinder highlights in green when it's achieved focus. BBF?

Something else to check out in the settings is the capture priority. I use release + focus. I think it's set to release by default, which means that the shutter will release even if it hasn't locked on focus. Focus priority means that it will wait until focus is locked before shooting (too slow and gets in the way). I prefer Release + Focus (good compromise).

 

[GrillMouster]

Yeah, I have that set which is why I'm so confused on where the focus fell when it shows me where it was aimed, kwim?

Hmmm. I know the function exists, but I don't use it. Maybe with non-3D dynamic AF it shows the selected focus point rather than the surrounding ones that it used to track.

Anyway, like I said, I don't like the camera tracking stuff on its own if I can't tell where it's shifting focus.

Even when 3D tracking "jumps around", because I have the AF function moved to the back button, as soon as it's locked on, I release the AF button before it can jump anywhere else (essentially locking focus).

 

[GrillMouster]

Another setting I change is the number of user-selectable AF sensor points. 51 is way too many to scroll through. I think I use nine or eleven (don't remember which is it). With that many I can always find a sensor that's close enough to the subject that I can focus & recompose, even at very shallow depth of field.

 

[GrillMouster]

Oh, and another thing (hahaha) the center focus sensor is usually the most accurate. Next in accuracy are all the cross-type sensors (the three center columns, fifteen cross-type sensors in all, which is a lot). The other sensors are only horizontal-type (I think), and not as accurate.

 

[wenrob]

3D can jump all over if the scene is dark, there's not much contrast, and/or there's something touching or really close to your subject that resembles the subject in tone or contrast. For example, two kids touching heads...It's very easy for tracking to jump around. That's why I jump to single-sensor AF. Tracking isn't necessary for static subjects; it can ruin things, like vibration reduction can ruin a tripod-shot image.

I shoot left-eyed, too, and I don't have a problem using the back AF button. I don't know if AF-C disables the audible focus-lock sound, as I immediately mute the camera as soon as I buy it. Besides, the viewfinder has a little dot that appears when focus is locked and the AF sensor in the viewfinder highlights in green when it's achieved focus. BBF?

Something else to check out in the settings is the capture priority. I use release + focus. I think it's set to release by default, which means that the shutter will release even if it hasn't locked on focus. Focus priority means that it will wait until focus is locked before shooting (too slow and gets in the way). I prefer Release + Focus (good compromise).

BBF-Back Button Focus
Yes, I have it set to Release+Focus
When I try to use the AF-L button I poke myself in my right eye with my thumb.

Hmmm. I know the function exists, but I don't use it. Maybe with non-3D dynamic AF it shows the selected focus point rather than the surrounding ones that it used to track.

Anyway, like I said, I don't like the camera tracking stuff on its own if I can't tell where it's shifting focus.

Even when 3D tracking "jumps around", because I have the AF function moved to the back button, as soon as it's locked on, I release the AF button before it can jump anywhere else (essentially locking focus).

But I'm not tracking, I'm using AF-S, single shot. It doesn't make sense that it would show me just what I selected does it? That would be kind of useless to have if that's all it did.

Another setting I change is the number of user-selectable AF sensor points. 51 is way too many to scroll through. I think I use nine or eleven (don't remember which is it). With that many I can always find a sensor that's close enough to the subject that I can focus & recompose, even at very shallow depth of field.

Going to try this. I am coming from 11, that's a huge leap, lol. I've never been a focus/recomposer.
I appreciate you taking the time.

 

[wenrob]

Oh, and another thing (hahaha) the center focus sensor is usually the most accurate. Next in accuracy are all the cross-type sensors (the three center columns, fifteen cross-type sensors in all, which is a lot). The other sensors are only horizontal-type (I think), and not as accurate.

Definatly going to drop the number of points down for now, so I'll keep that in mind. Now to find willing subjects...

I was telling DH I know the D90 in and out and probably subconsciously I'm expecting the D700 to react the same. I'll report back if I make any progress.

 

[GrillMouster]

...When I try to use the AF-L button I poke myself in my right eye with my thumb...

Sorry, didnt' mean to laugh at you.
I've never had that problem. I just am used to it. I don't really think about it; it just happens naturally. I don't try to put my thumb on the button after I've put the camera to my eye or move it away (that might cause poking). My thumb rests on the back AF button an my index finger rests on the shutter release button before I put the camera up to my eye and they rest on those positions after I've pressed the respective buttons. No poking.

But I'm not tracking, I'm using AF-S, single shot. It doesn't make sense that it would show me just what I selected does it? That would be kind of useless to have if that's all it did.

3D tracking only works in AF-C, but the other dynamic AF modes (9-point, 21-point, and 51-point) do work in AF-S (the switch in the front). For the other (not 3D) dynamic AF modes, it's the AF mode dial on the back of the camera that will determine whether it tracks. In single-point AF (the bottom option) it will not track.

The way I think about it, so I don't get confused, is that the switch on the front is for controlling whether the camera will track a subject moving toward me or away from me, but in the same spot within the frame. In AF-C it will continuously detect and adjust focus if the subject changes distance, but in AF-S it won't. The switch on the back controls the focus points with regard to a subject changing location within the frame (left, right, up, or down). 3D tracking requires tracking in all axis, so AF-C is required on the front switch and the crosshairs is required on the back switch. The other dynamic tracking modes are primarily interested in detecting whether a subject is moving up, down, left, or right in the frame (not just closer or farther), so they'll still work when the front switch is set to AF-S. When the back switch is set to single-point focus (bottom option) no dynamic tracking happens.

 

[wenrob]

Sorry, didnt' mean to laugh at you.
I've never had that problem. I just am used to it. I don't really think about it; it just happens naturally. I don't try to put my thumb on the button after I've put the camera to my eye or move it away (that might cause poking). My thumb rests on the back AF button an my index finger rests on the shutter release button before I put the camera up to my eye and they rest on those positions after I've pressed the respective buttons. No poking.

No worries, it IS kinda funny!

3D tracking only works in AF-C, but the other dynamic AF modes (9-point, 21-point, and 51-point) do work in AF-S (the switch in the front). For the other (not 3D) dynamic AF modes, it's the AF mode dial on the back of the camera that will determine whether it tracks. In single-point AF (the bottom option) it will not track.

The way I think about it, so I don't get confused, is that the switch on the front is for controlling whether the camera will track a subject moving toward me or away from me, but in the same spot within the frame. In AF-C it will continuously detect and adjust focus if the subject changes distance, but in AF-S it won't. The switch on the back controls the focus points with regard to a subject changing location within the frame (left, right, up, or down). 3D tracking requires tracking in all axis, so AF-C is required on the front switch and the crosshairs is required on the back switch. The other dynamic tracking modes are primarily interested in detecting whether a subject is moving up, down, left, or right in the frame (not just closer or farther), so they'll still work when the front switch is set to AF-S. When the back switch is set to single-point focus (bottom option) no dynamic tracking happens.

I think the problem I'm having is I have so many more choices, it's hard to keep it straight. I just finished reading this in the manual for probably the 100th time. Let me see if I have this:
If S on the front is selected and the single small box is selected, no tracking is supposed to happen right? It should focus where I put the box and that's it. If my subject or I move they'll most likely be OOF unless I get lucky. (which chances would be better if I had a handle of DOF on a FF camera)

If S is selected on the front and the middle box (cross hairs) is selected then I can select my point but it would possibly move to the next nearest sensor if my subject moved. Am I getting this? This is what I thought was initially happening and switched to S front, S back.

Reading (again) it seems I can only select a smaller # of focus points if I have the cross hairs selected. Otherwise, S front, S back gives me all 51 whether I want them or not.

Thanks so much for taking the time. It's frustrating to know what I'm doing but not know what I'm doing. Totally different beast!