Sony 70-400: A mount or EF with adapter?

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firehawk

Veteran
I'm looking at the sony 70-400 g2.
My goals are photo and video use for sony a6000 and nex ea50u (both aps-c) when I need to reach out and touch someone.
And also for video use with the fs700r (super 35) again when I need a longish lens.
In the distant future there may be something like an a7sII, a7rII or similar on the horizon, which I realize will have less zoom magnification due to sensor size.


Since it doesn't come in e-mount, am I better off using a canon lens with metabones adapter or getting it in A mount and using the la-ea3 adapter, concerning focus? Or would it require the la-ea4 for autofocus to work? Looks like the la-ea3 autofocus works with the lens, but not sure about working with the cameras.
 
It depends on if you need continuous auto-focus for your video work. If so, none of the options are good with an A-mount lens and the cameras you listed. I have the LA-EA4 and a bunch of A-mount lenses and there are tricks you can do with the AF button but I never rely on it for continuous auto-focus. (except for tight close-ups of my face, sometimes :D).
 
A couple things here. First, if it's a Sony lens, I highly doubt that it is even made
with a Canon EF mount.....Sigma and Tamron may make Canon mount lenses but
I really don't think Sony does. Canon may make a 100-400 but I don't think they
make a 70-400 like Sony does.

Second, Sony's adapter works MUCH better for autofocus than a Metabones (Canon to
Sony) adapter will. The Sony A to E adapter will limit you to F3.5, but at least it
will work. The Metabones is so slow, it's pretty much useless. As for differences
in the Sony adapters, I think the LA-EA3 is for APSC or Super 35 sensors and the
LA-EA4 is for full frame cameras. But that's the only difference. So a LA-EA3
would work for now, but if you are thinking about a full frame camera like an A7SII
or A7RII in the future, you may want an EA-EA4 to keep options open. Not sure why
you are being told that Sony A to E adapter is bad for autofocus, but it's honestly
about as good as you can get. It's 'phase detection' instead of 'contrast detection'.
This older video shows a bit about using A to E mount 'phase detection' on the
FS700......including the use of the very lens you are looking at!
https://vimeo.com/40369782
 
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I saw the shot with the Sony 70-400. He's shooting at 240 fps. LOL. In real time that shot of the surfer is a few seconds. Try a continuous auto-focus shot with an A-mount lens, the LA-EA4, 24 fps, and following an actor walking across a street. Ridiculous.
 
Thank you.
I was also looking at the sigma 50-500 which comes in EF or A. I forgot to mention that. I am leaning towards the Sony 70-400 hoping that sticking with a sony lens on a sony adapter on a sony camera might help reduce problems and help performance.
I understand the la-ea4 has it's own autofocus built in so it doesn't use the camera body for it. It also loses some light.
the la-ea3 requires the camera body to be able to do auto focussing if the camera can cooperate with the lens. I'm not sure if the fs700, ea50 or a6000 can do this with that adapter and lens.
 
You didn't say what type of video work you wanted to do. If you do run 'n' gun documentary stuff or live events you might wish you had a Sony e-mount lens. Their auto-focus is a lot smoother but still not 100% trustworthy. It can miss from time to time. If you do planned out, narrative stuff you might not need great auto-focus. The LA-EA4/A-mount combo is fine for me.
 
Viscount Omega said:
I saw the shot with the Sony 70-400. He's shooting at 240 fps. LOL. In real time that shot of the surfer is a few seconds. Try a continuous auto-focus shot with an A-mount lens, the LA-EA4, 24 fps, and following an actor walking across a street. Ridiculous.
Click to expand...

Oh I'd never say it's perfect, but it sure is a TON better than the Canon
alternative! The Sony A to E adapters (except for the EA-LA1) give you
phase detection autofocus instead of contrast detection. Not even sure
what a Canon lens via Metabones gives you, but if you think continuous autofocus
with an A mount lens is bad, try it with a Metabones and Canon lens! Of the
options the OP listed, it's FAR better to go Sony A mount with adapter.
Perfect? No.....but better than his listed alternative! I've done plenty
of successful autofocus work just as you describe....normal 24p.
Sometimes the lens is fooled but it works more often than it doesn't.
 
Thanks again.
The video work I would want this type lens for would be mostly events (outdoor wedding, dance recitals, speeches, etc ) where I needed a longer zoom due to being far back. Maybe some nature, automotive and sports too. We also do corporate and commercial work but usually don't need that much lens.

We shoot mostly 30p (slow action) and 60p (faster events) so possibly focus will be a bit better than with 24p.
 
OK. Lots of live moving targets. I would go with an e-mount lens and save myself the headaches. But it seems you don't want that. Some people use A-mount with an adapter in manual mode, hit the AF button to get focus, then hit record. Pain in the butt but workable.

If you use A-mount with an adapter on continuous auto-focus you might have to edit out some rapid focus shifts on the bride's face. LOL.
 
firehawk said:
LOL. :)
I appreciate all the help.
I wish there was an e-mount equivalent, but I am not aware of one.
Click to expand...
That's the thing. For autofocus, you are limited.
Sony A to E is the best option available in the focal
lengths you are looking at. You might try to rent the
lens and adapter and see how it works for you.
 
If going the A to E adapter route,
can any of the cameras listed do autofocus with the LA-EA3? Or will the LA-EA4 be required so then the adapter handle the focussing itself?
 
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