Video performance

The Sony a1 may be targeted at more of a stills/video hybrid shooter than, say, the company's video-focused a7S III, but both share a lot of core video features and the a1 of course is only the second stills/video hybrid camera to shoot 8K video, and the second of Sony's Alpha camera to shoot 10-bit video to either SD or CFexpress cards.

Key takeaways:

  • 8K video is very detailed, 4K video offers competitive detail against other high-resolution stills camera offerings
  • Excellent AF tracking while shooting video
  • 'Steadyshot Active' digital stabilization works in tandem with mechanical stabilization to produce extremely smooth video with negligible impact on detail
  • Controlled testing shows overheating isn't an issue, but this will necessarily vary depending on your shooting environment

Sony a1 video feature recap

We covered a lot of the video shooting spec in the 'What's New' page earlier in the review, but let's recap the highlights here.

Firstly, the Sony a1 shares almost all its video shooting features and modes with the existing a7S III, except that its higher-resolution sensor gives it the ability to shoot full-width 8K video at up to 30p, as 10-bit 4:2:0 H.265 footage at either 200 or 400mbps.

Full-width 4K is pixel-binned (merged neighboring pixels), which means it won't be as detailed as downsampling the 8K video to 4K, but the noise performance will still be comparable. If you can handle a 1.13x crop, you can shoot up to 4K/120p, and a further crop to an APS-C / Super35 mode gives you 4K that's oversampled from a 5.8K region of the sensor (so it's more detailed than full-width 4K but is likely to be a bit noisier).

Here's one more look at the most common video modes, capture regions, bit depths and codecs users are likely to take advantage of on the a1.

Frame rates Capture region Max Bit-depth/ chroma Codecs
8K 24, 30 8.6K FF 10-bit 4:2:0
  • XAVC HS
4K
(FF)
24, 30, 60 4.3K (binned)
FF
10-bit 4:2:2
  • XAVC HS
  • XAVC S-I
  • XAVC S
4K 120 3.8K (binned)
1.13x crop
10-bit 4:2:2
  • XAVC HS
  • XAVC S
4K
(Super 35)
24, 30, 60 5.8K
1.5x crop
10-bit 4:2:2
  • XAVC HS
  • XAVC S-I
  • XAVC S

V60 cards cannot be used for 4K All-I capture or bitrates above 280Mbps. All video modes can be recorded to V90-rated SD cards.

Sony a1 video quality

Now let's take a look at the Sony a1's video quality using our test scene. We can see that, as expected, the a1's 8K video is very detailed; against the EOS R5, it looks like the Canon is employing stronger sharpening that gives a bit more crispness. Dropping to 4K, we can see that if you choose the Canon's high-quality mode, which is taken from oversampled 8K capture, it looks far more detailed than the Sony a1 can muster; but drop the EOS R5 to its non-oversampled 4K capture, which it can shoot more reliably for long periods, and the tables turn somewhat, with the Sony a1 coming out ahead. The a1 has an oversampled 4K mode of its own, coming from an APS-C crop of the image; however, it comes from 5.8K capture, and so can't quite match the perfectly oversampled 8K-to-4K capture of the Canon. Both models have a 4K/120p mode, and the Sony takes an edge with greater detail though it does require a 1.13x crop while the Canon requires none.

The Sony a1 is also only the second full-frame alpha camera (along with the a7S III) to offer 'Active Steadyshot' stabilization, which means the camera uses digital stabilization (and a slight 1.1x crop) on top of in-body and in-lens stabilization to further smooth out handheld footage. It also writes the data from its gyro sensors into the file, to more effectively apply and fine-tune digital stabilization through Sony's software in post-production. There is a hit in terms of fine detail, so be aware of that, but let's take a look at a real-world sample as well.

Rolling shutter

Video mode Readout rate
8K/30p 15.2ms
Sub-sampled 4K/24p 7.8ms
4K/60p 6.9ms
1080/60p 4.6ms
4K/120p 6ms

The readout rates of the a1 when shooting video are impressive, as you might expect given the sensor's design. These figures mean that there's essentially no rolling shutter to speak of, it needn't be a concern regardless of which video mode you utilize.

Active Steadyshot image stabilization

The below video shows handheld video while walking through Seattle's Greenlake neighborhood. It opens with the stabilization in 'Active' mode before dropping to 'Standard,' and then no stabilization, and then enabling them again. Take a peek.

As you can see, there's a fairly remarkable difference in smoothness when the digital 'Active' setting is enabled, and at least in this situation, detail levels still look really good. Of course there is the slight 1.1x crop this mode enforces, and you'll notice it does take a few seconds to really kick in. Overall though, we think this is a small price to pay for its effectiveness at smoothing out up-and-down and side-to-side motion (though this will depend on many factors), as well as roll. So if the crop doesn't impact what you're shooting, we'd recommend using Active Steadyshot for any handheld situations where you may be walking with the camera.

Real-world test – 8K footage scaled to 4K plus autofocus performance

There are plenty of folks for whom 8K capture seems overkill, but nonetheless, there remain arguments for taking advantage of it for certain situations. Specifically, the ability to downsample 8K to 4K on an editing machine will give you 4K footage with greater detail and color resolution than the a1 can natively capture in 4K (since its internal capture is pixel-binned).

Shooting in 8K while aiming for a 4K export also gives you the ability to pan and crop in post, in essence, giving the videographer the opportunity to simulate a multi-camera interview even if they're only equipped with a single camera.

We filmed a short profile of Adam Chovanak and his business, Sodo Moto, which is a dealer in south Seattle that specializes in importing and selling Japanese automobiles. The video was filmed in 8K footage, and either downscaled or cropped in post to produce the output seen above.

We should also note that we relied exclusively on the camera's autofocus system for this video, utilizing tap-to-track for most shots, and relying on real-time face and eye detection for the interview shots. If you can't spot much hunting, well, neither could we: it's a really solid performance, and makes for easier run-and-gun style video as a small or one-man crew.

DPReview TV's take, including overheating

A while back, our Canadian duo (well, just one of them this time) took a look at what the Sony a1 can do, in admittedly covid-limited circumstances. But there are some significant takeaways here:

If you don't want to watch the full video above, which covers stills as well as video performance, you can skip to the video section by hitting this link.

The basic gist regarding overheating is that, at least in room temperature, there's not much to worry about. The camera easily recorded over an hour of 8K/24p video before overheating, and after a 15-minute cooldown, did it again. If you want slow motion capture, Jordan tested almost 30 minutes of recording at 4K/120p, and after a 15-minute cooldown, got 25 minutes of recording. Those are some seriously solid numbers for most types of video shooting (your mileage may vary, of course, in the desert sun, for example).