A6000 vs. A77ii Continuous AF - Very confused

Started May 14, 2014 | Discussions thread
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Re: Still the f/3.5 or smaller aperture restriction on low light continuous AF?
In reply to abortabort, May 27, 2014

d I think it is possible to do better. Also, it's known that when you rig a Minolta 50mm f/1.7 lens to be forced wide open, that the SLTs auto focus during video just fine! It means much better low light performance. Shallow DOF of course, but this could be ok. And then given that f/5.6 works fine (kit lens), and that probably it can handle at least f/8 (guessing here) without too too much trouble, I think that simply dictating f/3.5 and nothing else is just too draconian. I think that if a hacker group hacks that camera like some did with the Canons, one of the first things they'd do is fix these still things.

Yeah I kind of think it is lousy too, but we are likely to accept it's limitations in the field and realise where 'we' went wrong given the power allowed to us by the manufacturer (ie use at your own risk) but not many people are, especially those using ANY sort of AF in video (AF in video is patchy at best), so they will be less forgiving.

The A6000 does video with AF very well.

Just have a look how many threads of people complaining about the tracking of AF on the a6000, seems to me it works very well if you have some clue what you are doing, but many buying the camera expect every shot to be in perfect focus every time regardless of shutter speed or any other factor, like a mindreader because it is 'supposed to have great AF, worlds best they say!

The auto settings work reasonably well. Pick manual settings, and things get even better.

Well it sucks!

It's probably better than the A77 is. It might even be better than the A77ii is, in terms of AF. It's got many more PDAF points, and it has CDAF to supplement as well.

My daughter ran at the camera as fast as she could and all the pictures are blurry, this camera sucks'... Set at 70mm f5.6 1/10th ISO 100.

I think you're assessment sucks. Clearly, you have absolutely no idea what you're talking about. I've used it for a few weeks now, and tracking works pretty well. Perhaps if you picked something a little faster than 1/10th of a second, it wouldn't suck so bad. Again, clearly, unless you made a typo or something, your claims are flatout wrong.

Is it over the top? Maybe. But as I say, most professional use video will not use AF at all, in which case they can use any exposure values they want, the 'idiot proof' video with AF gets locked down to attempt to get the best results possible.

Most people that record video are normal every day people that shoot casual video around the house and on outings, of things like their family and the surroundings, the kids playing sports. AF needs to work well. The AF of the A6000 works very well.

The other issue as I mentioned before is that the AF sensors aren't all sensitive to larger apertures, nor smaller ones. They detect phase differences (like a split prism VF), but on larger apertures these are often 'too wide' for them to 'see' so they can't detect the difference and will hunt. Additionally they are often not 'that' sensitive to smaller differences which is what you will get with smaller apertures. So those AF points, even if they have enough light may not be able to 'see' properly the phase difference and will hunt until they can closer see the differences, hunting is not ideal in video. I would say that under testing f3.5 would be the optimum to maintain the best tracking with as little error and that is why they chose it. They allow smaller aperture values within reason but these are probably a compromise that they are willing to allow to enable as many lenses as possible to be used.

On the A6000 I can choose something like f/8 and track AF just perfectly fine.

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