strange focusing observation

[WayneF]

I have purposely set my a1 and a2 settings to Release Priority.

OK, but you might think that out again, since you are complaining that your pictures are not in focus.

 

[astroNikon]

I have purposely set my a1 and a2 settings to Release Priority.

OK, but you might think that out again, since you are complaining that your pictures are not in focus.

Yes, but as Derrel mentioned about the contrast.
My pics on the d7000 are focusing on a subject just on the edge of where I was focusing. On a player of the opposing team ironically who has a lighter shirt & an emblem with much more contrast.

I'll show some examples when I get a chance.
They are focusing .. just on the wrong thing. Derrel has seen some of the pics on my Facebook and there's a bunch on my Flickr too (of the better shots). I went quickly from my d7000 to the d600 last year and I know with the d600 looking back I have a much higher hit rate with the same lens. I was using my d7000 this past weekend.

 

[WayneF]

They are focusing .. just on the wrong thing.

Not focused on the thing your focus sensor was on? I would call that not focused.

Action is difficult, and there are multiple factors, and I am surely hard headed, but I don't see any disadvantage to pictures being in focus.

OK, sometimes (depending on how long you held half press first), Focus Priority might delay a small fraction of a second between shutter press and the focus actually allowing the shutter. But to bypass that focus check can only mean pictures that are sometimes not in focus, at least not at your chosen spot. I would give it a fair trial, but it is your choice.

 

[astroNikon]

Not focused on the thing your focus sensor was on? I would call that not focused.

Yes, precisely. But as mentioned my d600 seems to handle contrast (Phase Detection?) much better than the d7000.

OK, sometimes (depending on how long you held half press first), Focus Priority might delay a small fraction of a second between shutter press and the focus actually allowing the shutter. But to bypass that focus check can only mean pictures that are sometimes not in focus, at least not at your chosen spot. I would give it a fair trial, but it is your choice.

I only hold it half down for as long it is needed to focus. Then I release. I do this *alot* to keep the focus throw as short as possible at all times. And listening to my camera in Continuous mode, I think I focus more than the camera does.

my soccer game on Sunday was half on Continuous , half on Single. My Single mode was far more in focus than Continuous. Just the potential problem of continuous.

I know people think other people are whacko here
But this makes me think of the 70-300/3.5-5.6 lens which was a poor focusing performer.

My d7000 seems to not have the contrast detection as my d600 has. And that comparison between the two cameras was the crust of the thread. basically, the d600 having a slightly more updated phase detection than then d7000 which was driving me crazy.

I'm switching back to my d600 for the next game.
At the start of the season I tried my d600 with a 70-300 - which I did not like.
Then jumped back to a d7000 with the 80-200 for cropping advantage
but finding the d600 with a higher focus point accuracy is still the way to go.

In essence .. someone else with the exact same setup & action shots as me could test this.

 

[Derrel]

If you are going to shoot on AF-C with a screwdriver focusing lens, then set the focus either to back button AF-ON and let it focus ALL the time, continuously,by holding the AF ON button all the time, OR just use it normally, and leave the focusing associated with the shutter release and HOLD the button down so the lens can focus ALL the time, and shoot when the timing looks right.

If you elevate the ISO value to 1,000 or so in good daylight, you ought to easily be able to get to f/7.1, so you have some depth of field as a focusing cushion. At any youth soccer distance with the 80-200 lens, you ought to have adequate DOF to get you kid and close-by defenders in adequately decent focus. What is the DOF band at 45 feet at 175mm on FX, with the lens at f/7.1?

I do not get the idea of focusing only "part" of the time!!! I mean, what the heck are you thinking? You can only hear an AF-D lens re-focusing when it makes major changes in the focused distance. At longer distances, it's going to be very close to focused distance as soon as you pre-focus one time, and then as the kids move, the focusing will be extremely incremental over five,six,seven feet of distance and basically almost totally silent. If I am reading your description correctly, and you are deliberately NOT focusing in AF-C mode, the issue is with you using the AF system in a very oddball manner.

Again, AF-S focuses ONE time, and only shoots in-focus subjects. AF-S is for STATIC subjects, not sports. AF-C is supposed to be focusing/refocusing/achieving focus ALL THE TIME, constantly, and you need to allow it to do its job, not **** it up by trying to out-think the AF module and the entire camera.

 

[KmH]

The main mirror in the camera has a section that is 50% transparent.
That lets light tough the main mirror to a smaller secondary mirror behind the main mirror.
That secondary mirror directs light down to the AF module in the bottom of the camera.

You are not discussing Nikon SLR. I think you are talking Sony.

Nikon film SLR did use a sensor in the bottom of the camera, metering light literally reflected from the film surface when the mirror was up and shutter was open. Film TTL simply quenched the flash(es) off when metering was sufficient.

Nikon DTTL (first early models) still did this bottom sensor, but from a gray painted spot on the front the closed shutter. Mirror had to be up.

Nikon digital SLR (today) do the metering in the viewfinder, above the mirror..

The mirror is not at all transparent in any Nikon SLR.

This article has a graphic of a cutaway camera that shows the secondary mirror directing light passing through the main mirror to the AF module in the bottom camera.
It's an article about Canon AF but Nikon DSLRs are set up the same way.

Canon EOS DSLR Autofocus Explained

 

[WayneF]

The main mirror in the camera has a section that is 50% transparent.
That lets light tough the main mirror to a smaller secondary mirror behind the main mirror.
That secondary mirror directs light down to the AF module in the bottom of the camera.

You are not discussing Nikon SLR. I think you are talking Sony.

Nikon film SLR did use a sensor in the bottom of the camera, metering light literally reflected from the film surface when the mirror was up and shutter was open. Film TTL simply quenched the flash(es) off when metering was sufficient.

Nikon DTTL (first early models) still did this bottom sensor, but from a gray painted spot on the front the closed shutter. Mirror had to be up.

Nikon digital SLR (today) do the metering in the viewfinder, above the mirror..

The mirror is not at all transparent in any Nikon SLR.

This article has a graphic of a cutaway camera that shows the secondary mirror directing light passing through the main mirror to the AF module in the bottom camera.
It's an article about Canon AF but Nikon DSLRs are set up the same way.

Canon EOS DSLR Autofocus Explained

That is not Nikon. I do think the F3 and F4 WERE different, but not applicable today.

For anything applicable today, the Nikon meter is in the viewfinder.

 

[Mr.Photo]

While I do not know if it's the camera or the lens which is the initial problem, I will say that I've experienced a similar scenario to the OP's. I own a D7000 and an older 80-200 "push pull" lens. I was hired to be second shooter at a 5k and 10k marathon. We were setup on each side of the start finish line, and were capturing each of the runners as they came directly at us. I took over 800 frames of approximately 600 plus runners, and more than 2/3 of them were slightly off focus. I noticed this after reviewing all of the images, and of course so didn't the gentleman who hired me. We both came to the conclusion that it was the old tech lens not being able to keep up with the new focusing capabilities of today's digital camera's.

I did a test to see what my lens was actually doing when using AF-C on a subject as it was moving either towards or away from me. I found that if the object is moving relatively slowly (someone at a walking pace) the camera and lens can keep up fine. If the action gets much faster than that the AF seems to go back and forth in very small quick movements as it hunts to maintain focus which it doesn't seem to nail very often.

Doing this same test with my Tamron 70-300 VC lens (which is an AF-S type lens) yields very different results. It is able to lock on a single focus point, and track very quickly, and accurately compared to my old 80-200 2.8