Very attractive features. I was a bit disappointed that with such a nice feature set it appears to be limited to 8 bit recording even with HDMI out to an uncompressed recorder.

Cool. Now they should make some software that can edit it, and then some TVs to play it back on. (sarcasm) ;)

BTW I sent support a request for info on rendering and playing back on Sony TVs and their email back told me how to select "4K" in the rendering process... and that was all. Nice. Guess I'll wait until things become a tiny bit more standardized.

One quote from Lennie that really stood out -’If you have a 5D mkIII sell it now, buy one of these!’. Strong stuff and from what we’ve seen this seems to be about right if your focus is video.
http://www.newsshooter.com/2014/04/07/nab-2014-sony-a7s-video-interview-with-sonys-kanta-yakamoto-and-dp-den-lennie/

:D

Let us not forget about the Panasonic GH4 as well.
Also worth considering as an alternative to the Canon 5D MK III
GH3 may be worth a look for those not yet into 4K.
But no matter what you go with if you make the jump, it will cost thousands to trick out any of the above.
Still, for a lot projects I do the old Panasonic HPX170 is my workhorse.
Only drawback may be lack of shallow depth of field.
And it's not the best in low light.
For the time I'll live with those $hortcomings$.

I see the A7s as a bit of a game changer due to it's amazing low light capability. That does mean its capability as a still camera is somewhat limited as the sensor is only 12.5 megapixel although again it'll beat just about any other still camera for low light work.
Kudos to Sony for turning around the megapixel wars, they've done something that should have been done a long time ago.

Bob.

The Panasonic GH4 recently surpassed the BM4K on my pro and cons list. I wonder how the Sony will stack up? Another GH4 plus is Panny aready has a few years of super quality HD where as the competitors didn't do as well... so, why trust them for 4K if they can't get HD as good as Panny? just sayin :)

Couple of things stand out

- it's 1080P only without external recorder
- it's only 8 bit

Sony may be a little worried about competing with their own pro camcorder stuff.

[I]" Sony may be a little worried about competing with their own pro camcorder stuff."[/I]

Sony did address that to some extent, they wanted to keep the camera small.
We've got the Sony 4K RAW recorder that goes with the FS700 and F5. It's not just the size of thing, it also needs a brick battery bigger and heavier than the A7s.

Bob.

@farss >> it also needs a brick battery bigger and heavier than the A7s

Yeah, but the A7S on its own "only" does 1080P. For 4K you need an external recorder and, at the moment, a mains connection or a big heavy battery, so that's kinda moot.

Also, with the GH4 doing 4:2:2 10 bit out but the A7S "only" doing 8 bit... I guess it will come down to iso, noise etc. To me this looks like a camera that is just shy of being a player. It'll be interesting to see the real-world results.

http://www.sonyalpharumors.com/cinema5d-helped-on-the-a7s-development-and-believes-camera-price-will-be-around-2000/

[I]" It'll be interesting to see the real-world results. "[/I]

Real world results have already been posted. The low light and dynamic range are quite impressive. Obviously it's not direct competition to the likes of the F55 but it can get into places that the F55 cannot and it's a lot cheaper.

I'm actually tempted by this camera. 1080p is enough for my audience, I doubt I'll ever shoot something for the silver screen but there is stuff I do shoot for fun that this camera would do better at than what I already have.

Bob.

I was watching some GH4 reviews and just found out that it also does 1080p 96fps which will make for some great slow motion video.

For the pros among us there's a neat XLR and Time code BNC module that connects to the base.

One of the reviews pointed out is that there's no stabilization?

GH3/4 can't have in-body stabilization because there is not enough room for an adequate heatsink. As codec bitrates increase, so does heat on the circuit boards. GH4 maxes out @ 200Mbps for 1080, 100Mbps for 4k. Sony A7s I believe sports a 50Mbps codec for 1080, 60Mbps (?) for 4k.

Great sensor on Sony may be handcuffed by lousy codec. We will see.

Sony doesn't have internal 4K encoding of any kind. They're claiming it's to keep the camera small, but ... well... it's larger than the GH4. Of course, it does have a full frame sensor.

And that's some sensor. Sony lost on low light with the more recent, super high-pixel count Alphas. This more than makes up for it. Sure, only 12.5Mpixel, but that's going to grab a ton of light. My Canon 6D can do AF down to -3EV; this does it to -4EV. And even though I don't quite believe the insane ISO numbers, it's likely to stay excellent at higher ISOs than most any other camera. So for video, a total knock-out.

It's interesting that everyone who's not Canon or Nikon is working out how they can compete by making things different. I'm drooling a little over the GH4 -- I have an m43 system as well as my Canons -- because it's really the first DSLR I've seen that makes me jealous for video purposes. So, ok, smaller sensor, but in-camera 4K, HD at 200Mb/s, shooting as long as you like (none of this 29'59" "because Europe" BS... I live in New Jersey, not Jersey), etc. And the add-on box, which make it a better camcorder in some situations than any other DSLR so far.

And now Sony, also shooting straight at the Canons, particularly the 5DmkIII but also now the 1D C, with their own superset of features. I do wonder just how much Canon can compete here, given their need to not undercut both their own camcorders and their EOS C series.

Another big win in the GH4 (not sure about the Sony)... they no longer have the RIDICULOUS limit of 29'59" Canon insists on shoving down our keesters, even though the only reason that's still done is to avoid a European tax on camcorders. Which of course, is a non-issue for those of us living, say, in the USA.

I'm currently using Canons for DSLR duty. But I actually have a small m43 system, originally bought to keep from sinking to the level of P&S if I just didn't feel like dragging along a full Canon rig. Not something I currently use for video. But between the crazy good lenses out for m43, and bodies like the GH4 or even the OM-D for stills, I'm seriously considering adding a GH4.

I'm also wondering how Canon can really compete here. They have a great product line, if you're a higher end pro: EOS 70D, EOS 5D mk III, 1D C, C100, C300, C500, etc. On the other hand, they kind of have to protect that market, and launching a 4K model at the price I pay for a new video device (around $2K) doesn't seem likely.

And it's clear that Panasonic and Sony don't worry too much about protecting the higher prices in this market, but would rather take some share away from Canon. Sure, it'll cost a bit to come into this from scratch, but hell, it's even technically possible to use your EOS lenses on a m43 body (though the Metabones Speedbooster, the one EVERYONE has been waiting for, is still a no-show). I'm not doing sound on-camera much anyway. So from my view, it's only the $1700 plus a few batteries.

Well, I've got to say it... every time I see this thread pop up, I read it as "Sony Officially Announces AK47s."

...Jerry (not getting old, but IS old)

Jerry, I almost posted the same thing earlier today! I keep misreading "4K A7" as "AK47" -- and I'm not even a gun owner.

And even though I'm more of a handycam amateur user, I'll ask a question here about these DSLR -type cameras:

These cameras don't have built-in ND filters -- which I love having on my FX7. Does the "multi ISO" nature of these cameras mean that ND filters aren't needed for normal outdoor shooting? Obviously a film crew might put a matte box and filters in front of the lens, but is "no built-in ND" an issue for more casual use of cameras like this for video?