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Noa Put September 10th, 2014 01:04 AM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Michael Stevenson (Post 1860715)
if you shoot in 60P NO rolling shutter.

Quote:

Originally Posted by Michael Stevenson (Post 1860715)
I'm not saying it's not there in every case

So what is it now, is there or is there not? :)

The camera has rolling shutter and it can be bad depending in which situation you use it, it doesn't even have to be a fast pan like this example shows:
Shooting in APS-C reduces the RS though but it will never be completely gone. RS should not be a problem for most of us depending on your shooting style but it can make the camera useless if you for instance shoot a soccer match with a telelens and follow the players while panning, but then again, you should use a videocamera for this purpose and not a full frame photocamera.

Alister Chapman September 10th, 2014 01:09 AM

Re: New Sony A7s to shoot 4K video
 
There is more rolling shutter than most dedicated video cameras. It's not just zoomed in shots or whip pans where you may find issues. Vehicles moving through a shot or shooting from a moving vehicle will all show rolling shutter artefacts. Even a mid speed pan across any strong verticals such as telegraph poles or tall buildings will show it up. But almost every other aspect of the images from the A7s are so good that I'm happy to simply avoid these types of shots with this camera. I'm lucky though, I have other cameras, so I can fall back to these when I know I may encounter RS issues. For me the A7s strength is I can pop it in a large pocket or sling it over my shoulder and take it just about anywhere and in most situations get video that is really frighteningly good considering what the camera costs.

As an owner of both the A7s and AX100 if I had to choose one which would it be? That's tough because although they really are very different cameras they both have strengths that are nice to have. The A7s produces a prettier picture and can be used run and gun, with limitations. I use the kit 28-70mm f3.5-f5.6 and it works well, good auto focus, smooth aperture changes etc. BUT and it is a very big BUT you need a really good set of ND's or a strong ND fader to use it outdoors due to the extreme sensitivity. Add to that the minimal 3x zoom and it's pretty restrictive as to what you can shoot without switching lenses and fiddling around. Sure you can add something like the new Tamron 16-300mm f3.5-f6.3 but the autofocus tends to hunt a lot more, manual focus is fiddly and you still need to mess around with ND's. I think you need to be a fairly competent cameraman and need to be very careful over lens choices etc to use the A7s for run and gun successfully. Plus don't forget the cost of all the extra lenses, filters etc adds up and makes the kit bulkier.
The AX100 on the other hand really is a grab and go camera. Easy to use, great zoom range, built in ND's. It's quick and easy to use and may get you shots that you will miss with the A7s. But the pictures are not as pretty, primarily it lacks the dynamic range of the A7s. But it is very easy to use, so well suited to those that are full auto shooters or rely heavily on auto functions to keep life simple. It's also a very compact package and as you don't need to buy extra lenses or filters it works out substantially cheaper.

Anyway, if I had to give up one, for me it would be the AX100 that would go. I would be prepared to sacrifice the ease of use of the AX100 for the better images from the A7s. But I normally shoot manually anyway. I'm used to swapping lenses, working with ND filters etc. The best camera to own is a camera you will use. It's all very well having fancy pictures and the ability to swap lenses etc. But if fiddling around means you don't use it very often, then there is no point in having it. You would be better off with a camera that you will be comfortable with, that you will use regularly.

Michael Stevenson September 10th, 2014 08:06 PM

Re: New Sony A7s to shoot 4K video
 
Thanks guys, I am a better photographer than a writer by far. But the incredible clarity (low light, reflections and bokeh) of the video is very usable. I bought the Camera + Shogun so I could shoot some 4K video and start working with it before most folks will ever do. I really think a Sony A7s forum should be added here.

More handheld in very low light:


Michael Stevenson September 10th, 2014 08:08 PM

Re: New Sony A7s to shoot 4K video
 
Another clip:


Cliff Totten September 12th, 2014 11:44 AM

Re: New Sony A7s to shoot 4K video
 
We know the Atomos Shogun 4k HDMI recorder is on the way soon.

Many Sony A7s owners are planning on using the Shogun with the A7s. (In fact Sony is relying on the Shogun recording option as a selling point for the A7s against the GH4)

One of the biggest selling points of the A7s is it's SLOG-2 feature. On another forum it has been noticed that the A7s actually does NOT output SLOG-2 via it's HDMI port. (Sony underhandedly reverts it to REC 709?)

Can anybody confirm this? If this is so, why would Sony deliberately mislead their customers on the A7s? Nowhere is it stated in any documentation or description that the SLOG-2 is disabled over HDMI.

I'm hoping this is a mistake...or,...Sony is fixing this potential PR disaster soon in a A7s firmware update.

Somebody tell me that this information is COMPLETELY WRONG! (it must be wrong. I cant believe Sony would do that without stating that to their buyers first)

CT

Evan Donn September 12th, 2014 04:00 PM

Re: New Sony A7s to shoot 4K video
 
Seems unlikely - this review has some tests with SLOG via external recording and it appears to work:


Michael Stevenson September 12th, 2014 07:31 PM

Re: New Sony A7s to shoot 4K video
 
Please do not watch my clips here. Watch them on Vimeo. They are highly compressed here. Wow!

Cliff Totten September 12th, 2014 08:01 PM

Re: New Sony A7s to shoot 4K video
 
I posted more of this on the Convergant Design 7Q 4k thread.

Did a test tonight between SLOG-2 recorded on XAVC-S internal vs. SLOG-2 recorded over HDMI.

Comparing both files on wave form scopes show some big differences. The XAVC-S file, the SLOG-s is nice and flat. However, the HDMI recorded file has substantially more contrast. Highlights at 70 IRE on XAVC-S were spread further up the scale to 80 IRE. Shadows that registered 10 IRE internal were now spread down to 0 IRE on the HDMI port.

I'm hoping A7s owners will do their own tests to confirm this. It's a bad thing that I hope we can get resolved soon.

I hope this is not a Sony "cripple" to make sure that true SLOG-2 is trapped inside it's internal 4:2:0, 1080 codec.

Right now, I'm giving Sony the benefit of the doubt and see what they say about this.

CT

Michael Stevenson September 12th, 2014 08:05 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Cliff Totten (Post 1861259)
I posted more of this on the Convergant Design 7Q 4k thread.

Did a test tonight between SLOG-2 recorded on XAVC-S internal vs. SLOG-2 recorded over HDMI.

Comparing both files on wave form scopes show some big differences. The XAVC-S file, the SLOG-s is nice and flat. However, the HDMI recorded file has substantially more contrast. Highlights at 70 IRE on XAVC-S were spread further up the scale to 80 IRE. Shadows that registered 10 IRE internal were now spread down to 0 IRE on the HDMI port.

I'm hoping A7s owners will do their own tests to confirm this. It's a bad thing that I hope we can get resolved soon.

I hope this is not a Sony "cripple" to make sure that true SLOG-2 is trapped inside it's internal 4:2:0, 1080 codec.

Right now, I'm giving Sony the benefit of the doubt and see what they say about this.

CT

Fascinating. What were your HDMI out settings and what do you record it on?

Cliff Totten September 12th, 2014 08:14 PM

Re: New Sony A7s to shoot 4K video
 
Samurai Blade via HDMI to SDI.

30p A7s recording and 60i HDMI (Using Atomos 2:2 pulldown)


I'm now testing using BlackMagic shuttle (completely different recorder)....will have those results in 30 min.

So far, I'm very surprised that only the Convergant Design team has noticed this and really spoken about it.

They are saying that the A7s SLOG-2 HDMI output is really closer to REC 709 than the "true" SLOG-2 internal recording.

If this turns out to be a creative Sony "cripple" trick, I'm going to be LIVID if they refuse to fix it.

I'm not saying it is yet. I'm hoping it's a simple "bug" that Sony will fix.

Looking for more A7s testers out there,.......

CT

______________________________

Edit - I now have TWO recorders (Atomos and BlackMagic) that both confirm the same result: The A7s HDMI port ADDS contrast back to the SLOG-2 signal. Again, highlights that are 70 IRE internally are now spread to 80 on the HDMI port. Same for the shadows too, 10 IRE internal are crushed to 0 IRE on HDMI (The entire wave form shows a SIGNIFICANT difference between internal recording and monitoring and actual HDMI out)

Calling all A7s owners. Please post your own test results! We need to shake the Sony tree on this problem.

I gotta find Alister and get him to see this......

Michael Stevenson September 12th, 2014 08:54 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Cliff Totten (Post 1861261)
30p A7s recording and 60i HDMI (Using Atomos 2:2 pulldown)

I'm not feeling that.

Cliff Totten September 12th, 2014 09:03 PM

Re: New Sony A7s to shoot 4K video
 
2 Attachment(s)
BlackMagic 60i HDMI capture....exactly the same problem. This is not an interlacing or pulldown problem.

Looking for more A7s testers with any HDMI recorder.

1.) Record a SLOG-2 internal XAVC-S file.
2.) Record via HDMI to any recorder that you have.
3.) Compare both files on a scope...you will see that the SLOG-2 gamma curve has been stretched and "damaged". (compared to internal file's "proper" curve on the scope)

Again, Convergent Design posted this problem not long ago on their thread.

CT

Check out the scopes. Everything above 20 IRE shifts (stretches) up...below 20 IRE shifts (stretches) down.

Edit: As you can see in the histogram, the SLOG-2 gamma log is certainly destroyed.

Steve Kimmel September 12th, 2014 09:55 PM

Re: New Sony A7s to shoot 4K video
 
I rented an A7s a few weeks ago and can confirm the same issue recording to a PIX240i.

Dan Keaton September 13th, 2014 05:45 AM

Re: New Sony A7s to shoot 4K video
 
Dear Friends,

This issue can be easily shown without a video recorder.

Just connect an A7s (set to S-Log 2) to any HDMI television.

The image will not look like normal S-Log 2, it will not be "flat", there will be more contrast.

This is not a recorder issue.

Personally, I believe that this is not an attempt to cripple this camera.

Of course, we would like Sony to allow regular S-Log 2 to be output the HDMI port, when S-Log 2 is enabled in the menu.

Respectfully,

Steve Kimmel September 13th, 2014 06:30 PM

Re: New Sony A7s to shoot 4K video
 
There is some suggestion on another forum that the s-log out of HDMI problem could due to which HDMI cable one uses.

Cliff Totten September 13th, 2014 07:26 PM

Re: New Sony A7s to shoot 4K video
 
Someone is saying that the HDMI cable itself is changing the 0's and 1's that are passing through it?

That doesn't make any sense to me. The signal is either there or not there.


CT

Cees van Kempen September 16th, 2014 10:04 AM

Re: New Sony A7s to shoot 4K video
 
Does this also have influence on the low light abilities?

I am considering to use the an a7s for extreme low light shoots for a wildlife documentary, with a Shogun.

Emmanuel Plakiotis September 16th, 2014 02:11 PM

Re: New Sony A7s to shoot 4K video
 
I think the new 24-135 F4 zoom that kits FS7, should be bundled with this camera instead. I can't understand why Sony doesn't promote it. Maybe there is a FF video camera on the wing...

Dmitri Zigany September 16th, 2014 03:39 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Emmanuel Plakiotis (Post 1861709)
I think the new 24-135 F4 zoom that kits FS7, should be bundled with this camera instead. I can't understand why Sony doesn't promote it. Maybe there is a FF video camera on the wing...

The 28-135 won't be shipping until December, and the FS7 is still a month away I guess. They were announced at the same date so bundling them makes more sense. Bundling a lens with a camera that costs less than the lens itself also makes less sense.

Michael Stevenson October 5th, 2014 09:45 PM

Re: New Sony A7s to shoot 4K video
 
1 Attachment(s)
Lovely evening at the Alderwood Mall. Sony A7s Full 35MM sensor, hand held, tack sharp RAW, in very low light.

Michael Stevenson October 5th, 2014 09:54 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Dmitri Zigany (Post 1861719)
The 28-135 won't be shipping until December, and the FS7 is still a month away I guess. They were announced at the same date so bundling them makes more sense. Bundling a lens with a camera that costs less than the lens itself also makes less sense.

I have purchased the FE 24-70mm and the 70-200mm Zeiss/Sony lenses and they are fantastic. Soon I will get the 16-35mm lens. Bottom line is they auto focus stunning video and great Photos.

Evan Donn October 6th, 2014 12:15 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Michael Stevenson (Post 1863800)
Bottom line is they auto focus stunning video

I guess it depends on your shooting style - I personally still prefer manual focus for video. Rented the 24-70 for a week and the manual focus is terrible, borderline unusable in my opinion. The weird mapping of rotation speed to focus speed results in a lot of hunting for the right focus, which is what you're trying to avoid by focusing manually in the first place. If they can provide an option for linear mapping of the rotation to focus it might be better, but even then slow focus changes exhibit visible stepping of the focus point rather than smooth transitions. For the price (and specifically for video use) I'd rather have the rokinon 24/35/85 t/1.5 cine prime set - certainly not as convenient as a single zoom, but far better manual focus plus much faster apertures and useable with a follow focus.

Graham King October 7th, 2014 12:33 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Evan Donn (Post 1863873)
If they can provide an option for linear mapping of the rotation to focus it might be better

Don't all lenses change focus distance on a logarithmic scale?

Evan Donn October 7th, 2014 01:50 PM

Re: New Sony A7s to shoot 4K video
 
Hmm, hadn't thought about that, but I guess that's true. That would be fine though - my point is that it would be better if sony provided a way for the focus ring rotation to map to the focus change in a manner which matched what you'd expect from a true manual lens.

The way the sony manual focus works is that if you turn the ring quickly - even a very short distance - the focus point jumps dramatically. If you turn it slowly it changes extremely slowly. This is frustrating because what typically happens (at least for me) is you start to turn the lens and the focus jumps farther than you expected, overshooting the target. Then you react to this jump by slowing down as you try to pull the focus back, but the speed drops so slow that it takes too long to pull it back. Finding just the right speed to turn it at is extremely difficult, and it feels fidgety. You can't really practice pulls, because if you don't maintain the same speed it'll be different each time - it's fairly easy to repeat turn angles, but difficult to match an exact rotation speed. To make it worse, when it drops down to the very slow speeds you can see it visibly changing focus in steps - it's subtle, but noticeable.

I get what they were trying to do from a technical standpoint - they idea is clearly to let you jump quickly to an approximate distance and then provide much finer control as you refine the focus point. That's probably a great way to work if you're using manual focus for stills where all that matters is the final focus point. It's just not good at all for video work where the focus moves are part of the shot and you need to be able to predictably and repeatedly execute smooth, controlled focus moves.

Graham King October 7th, 2014 02:37 PM

Re: New Sony A7s to shoot 4K video
 
I see what you're saying. The ring itself isn't locked to the internals but rather controls them electronically. Sounds like that'd make pulling focus very frustrating.

I've got my eye on those new Zeiss Loxia lenses. Just ordered an a7S which is why I'm here. Very excited to have this as my new b-camera to my C300 and finally putting the HDSLR revolution behind me with the sale of my 5DIII. Long live the 5D.

Alister Chapman October 8th, 2014 05:32 AM

Re: New Sony A7s to shoot 4K video
 
Now you're talking. Loxia's on an A7s, that's a great combo. I got to shoot with some on the FS7 and they produced some really amazing images.

Michael Stevenson October 20th, 2014 08:26 PM

Re: New Sony A7s to shoot 4K video
 
Quote:

Originally Posted by Noa Put (Post 1860780)
So what is it now, is there or is there not? :)

The camera has rolling shutter and it can be bad depending in which situation you use it, it doesn't even have to be a fast pan like this example shows:
Sony A7S - rolling shutter - S-LOG 2 - internal 1080p recording on Vimeo
Shooting in APS-C reduces the RS though but it will never be completely gone. RS should not be a problem for most of us depending on your shooting style but it can make the camera useless if you for instance shoot a soccer match with a telelens and follow the players while panning, but then again, you should use a videocamera for this purpose and not a full frame photocamera.

Ouchy! :-)

Richard D. George November 24th, 2014 08:30 AM

Re: New Sony A7s to shoot 4K video
 
Rolling shutter is supposed be be less using the APC mode on the A7s.


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