Good news! Super 35mm mode on Sony A7S dramatically reduces rolling shutter


All footage by Ed David on the EOSHD forum

I’m surprised at how nice the quality is from APS-C (Super 35mm) mode on the A7S. I expected it to be a lot softer! There’s no signs of significant moire or aliasing either.

The smaller window from the sensor allows the shutter to expose the whole pixel readout more quickly than in full frame 12MP mode, so less jello for us.


120fps (720p) from Ed David


APS-C crop mode frame from Ed David


The internal 1080p image from the A7S looks to be the best Sony have ever produced on a consumer camera.

Banished are memories of the NEX-VG900 or the moire and aliasing problems of the A7 and A7R.

It is far more finely detailed than the image from the 5D Mark III and yet avoids moire and aliasing to about the same degree – that is none noticeable outside of chart tests. The APS-C / Super 35mm crop mode does soften fine detail a little bit but again it’s a world apart from APS-C mode on the A7R.

Now the APS-C mode has much less skew than in full frame. How should we use it on a shoot? Well for fast action shots and violent handheld camera-work I advise switching to this mode. It also raises the possibly of using the Metabones Speed Booster to maintain that full frame look in Super 35mm mode along with less skew… Then for more stiller, moody low light dialogue scenes for example you would have no issues using the proper full frame mode with the longer 30ms rolling shutter scan.

Here’s the detail in 1080p, from a 1:1 crop of Ed’s footage…


And the full APS-C 1080p frame grab (click to enlarge)…


How the APS-C mode is handled in 4K mode is a point of interest going forward. I’m expecting it to look a bit like 3K upscaled to 4K. Given plain old 1080p looks very nice and detailed from the 1D C in Super 35mm mode over HDMI, this should still make for some of the best HD image quality around and could still intercut nicely with real 4K.


The full frame slow mo sequences in Ed’s video are also much better looking than I would have expected given the semi-pro / consumer nature of this camera. Again no real signs of heavy moire and aliasing, detail looks like 1080p on the 5D Mark III – softer than the 24p mode of the A7S but dare I say it better than 96fps on the GH4…

So the A7S continues to surprise and this is just out of the box 1080p.

We haven’t even got an elegant way to record 4K from it yet but you can bet your house on the fact I will be using an Atomos Shogun with this camera.