Where Sony has been clever is in keeping exactly the same handling and build in each generation, but producing three very different cameras by using different sensors and processors. The result is that there is an all rounder, the A7, a high resolution camera, the A7R, and a low-light camera for videographers, the A7S. Things changed a little with the second generation, and the A7R II offered not only an incredible 42-million-pixel resolution, but also improved video capabilities, including 4K internal recording. With this in mind, it was no surprise when then A7S II was announced and it also featured 4k internal recording, as well as a few other tweaks to keep videographers happy.
We’re going to assume that you already know a little about the A7S. If you don’t you can read the review on Amateur Photographer. For now, we’ll be concentrating on the camera video features, and most importantly, how they compare to the original A7S.
First off, the sensor. The A7S II has a full frame CMOS sensor with a 12.2-million-pixel resolution. This is largely the same as the sensor found in the predecessor, though its performance is said to have been in proved through processing. In truth we have not really seen any visible difference. The most impressive part of the sensor remained unchanged, and that is its extraordinary sensitivity. The camera has a sensitivity range of ISO 100-102,400, which can be expanded to an incredible ISO 409,600. Obviously noise is introduced at these higher sensitivities, but what is impressive is that the noise is still well controlled where other cameras would be reaching close to their maximum sensitivity. Just a quick note here, if you shoot using the S-Log 2 or S-Log 3 settings, the native sensitivity is ISO 1,600. More on this later.
So what can the Sony A7S II record? Well the camera has a 4:2:0 8-bit sampling when saved to an internal SD card, though it does offer 4:2:2 output through the HDMI connection. Again, more on this later. In terms of resolution and frame rates, it can shoot 720p at 25 or 30fps, but who really cares about that these days? The real numbers start coming in when you hear that the A7S II shoots full 1920×1080 at XAVC HD footage at frame rates of 25fps (50Mbps), 50fps (50Mbps) and 100fps (100Mbps or 60Mbps). At 100fps that means that PAL shooters can produce 4x slow motion footage. Footage can either be slowed down in editing software, or if you select the in-camera HFR mode, it is saved in camera as 25fps footage, so you can see it at the reduced speed on the rear screen.
Unlike the original A7S, the second generation camera is able to record 4K footage internally to an SD card. Again, the footage can be shot at 30, 25 or 24fps, with both 100Mbps or 60Mbps data rates.
SD Card Storage and compatibility
One word of warning is that the 4K, and the 1080 100Mbps modes require UHS-I U3 class SD cards to be able to record. If you use a card that doesn’t meet this standard then the camera will warn that the card isn’t compatible and ask you to insert a U3 card or change the recording format.
I tried a few different cards and whilst I didn’t have an issue with using a Panasonic SDXC UHS-I U3 card, the A7S II refused to use a Samsung UHS-I U3 card. I even tried reformatting the card in-camera to no avail. I believe it is a fault with the Samsung card, as I have read nothing about any other cards denoted as U3 having this problem, However, to be on the safe side I would make sure that you are using a card that is known to work before you head out on a shoot. However, I prefer the warning screen to using a non-compatible card and suffering from dropped frames.
As you would expect the camera can record video in either Program, Aperture or Shutter Priority and, of course, fully manual exposure modes. Zebra patterning is available with settings ranging between 70 and 100+, but there are also 2 custom settings which can be useful if you tend to exposure your footage in a certain way. You can specify a specific lower limit at any value above 50%, or you can specifiy a Std+Range value, which will show the zebra patterning at a specific value and a set ± range between 1-10. For example the standard value is 95% with ±5, anything between 90-100 will have a zebra patterning. You may ask ‘why not just use 90+?’, well the answer is actually for exposing skintones rather than highlights. Skintones are generally aceepted at being perfectly exposed between around 50-80% based on the subject. If you set the zebra to, say 70 ±10 you should be able to check that the subject of your footage is perfectly exposed.
Focus magnification and focus peaking are also there to assist you, and with the addition of 4k shooting it is important to make sure that your focus is spot on as any slightly soft footage will be even more noticeable than when capturing Full HD. Some online commentators have said that the 4x magnification is not good enough to get really pin sharp focus using the rear screen, however, I haven’t had any difficultly. Even when using a vintage Nikkor 50mm f/1.4 lens, at f/1.4, I found that just using the screen I was able to get the focusing pretty much spot on, and then zooming in to 4x just made it perfect. I compared the 4x focusing to the 8x focusing available for still images, and found that, having focused at 4x, the 8x wasn’t actually needed, it was already spot on.
In terms of audio there are two 3.5mm headphone and mic sockets on the side of the camera, as well as an internal stereo microphone. When using an external microphone with the A7S II we were very impressed. In particular the Sennheiser lavalier mics sounded very loud when first plugged in, in fact we had to turn the recording volume down to almost minimum in the Sony A7S II. The recorded sound was very clear and crisp, particularly for spoken word. The internal pre-amps are excellent.
What’s missing? Well, not a lot really. The only addition that I can think of would be an internal ND filter. Obviously this is easier to facilitate in dedicated video cameras. However, given that the FS5 has an electronic variable ND filter in front of the sensor, and that the new Sony RX1R II has a variable low-pass filter based on, what looks like very similar technology to the ND filter in the FS5, it wouldn’t surprise be to see such a device in the third generation of these cameras. We shall see.