Using the NEX-7 yesterday, I noticed in autofocus mode a disconcerting behavior that makes the camera feel nervous and unstable: the NEX-7 cycles the lens repeatedly while the user is doing nothing: it defocuses and refocuses. This is apparently a “feature”.
The interval varies: it can be every second continually for a minute, or hardly ever, or every 10 seconds and so on.
By itself this constant noise and focusing activity is annoying, but it also chews up battery power and made me think the camera (or lenses) were defective. I’ve since learned that this is a “feature”.
But when composing an image it is downright insane (or might make me go insane): I’m engaged in the scene trying to compose, and every 2 seconds the view goes blurry and then refocuses (or every second or every 10 seconds, it’s seemingly random). It’s incredibly damaging to my ability to use the camera and focus on image-making.
How could anyone at Sony think this is anything but a serious bug? It demonstrates how the market cries out for good design in all the details. A camera is not just the latest fancy sensor or screen; it has to be a usable whole.
Add to this the constant changes to camera settings, the NEX-7 is driving me crazy: dials that all but change themselves at a breath of air—I’m suddenly back at auto-ISO or with -2 stops exposure compensation or making a movie (and my images are seemingly all missing because the camera changed folders to the video folder), or in P mode instead of M. Locking the controls is not an answer; I need to use them.
I thought I was being too harsh on the NEX-7 in calling it a “game console” in previous posts, but I reiterate and re-emphasize that statement: this is a toy, not a serious tool.
Readers suggest workarounds for the autofocus issues below, basically decoupling the autofocus from the shutter.
Jeff K writes:
Default behavior with the NEX 7 is for it to continuously focus when in AF mode. Here's the best way I've found to control this behavior.
First, set AF mode to MF.
Next, in Setup menu under custom key settings set AF/MF button to AF/MF control.
Next, in Setup menu set AF/MF control to "Hold" (not "Toggle").
With the camera set up this way, you initiate AF by pushing (and holding) the AF/MF button and when you release pressure from the button the camera stops autofocusing. This is very handy for me since it's the way I always set up my Nikon and Pentax DSLRs. I find it very useable because since I have MF assist on, I can first AF by pushing the AF/MF button, then if my subject is not moving and I want to double check focus I can release pressure on the AF/MF button which puts me back in MF mode, turn the focus ring on my lens which automatically puts me in magnified view to double check focus. Then, a half press on the shutter button gets you out of magnified view to double check composition/framing before taking the shot.
DIGLLOYD: A workable solution for this particular issue.
Yep, it's a common complaint about the NEX-7 AF that I'd imagine will be fixed in a firmware update. The good news is that the NEX-7 has the rear AF/MF button. What I personally do is leave the camera in manual focus, and press the AF/MF button to autofocus. Make sure you set AF/MF control to "hold," and map the AF/MF button to "AF/MF control" in the setup menu.
Doing the above will stop the constant pre-focus and save you battery life. A lot of DSLR shooters shoot this way, because it decouples metering from AF, which is nice, IMO.
I have a NEX-7 (and NEX-5N, and NEX-5) it doesn’t do this. I wouldn’t be able to use it if it did. I don’t have it in front of me right now, but perhaps you could just check if you could set the AF mode to AF-S instead of AF-C?
DIGLLOYD: including my camera, three readers have confirmed this behavior, a total of four. So I have no explanation to offer, unless perhaps HZ has disabled autofocus when the shutter is pressed, as is the tip given above.
Andrew B writes:
A HUGE thank you to the other readers who respnded and to you for publishing their responses. I had made numerous attempts at decoupling the AF from the shutter button in the past, but had never found a working combination with the NEX-7. I have set up current and past DSLR's AF using the AEL or AFL buttons, and I much prefer this method. Anyways, this little trick has brought new life to my NEX. It is instantly more reliable!
That said, I wanted to point something out that I am just now noticing with the new settings applied. Beyond getting rid of the periodic AF hunt glitch, I have noticed that the camera will also keep the focus setting in tact when the cameras power is cycled. Considering the amount of careful tripod work you do, I'm sure this is welcome news!
DIGLLOYD: I’m glad to hear this! However, I do not see that the focus remains unaffected by power cycling the camera.