If you find yourself wondering 'why would I even want an external monitor/recorder' then I'd suggest you spend a few moments reading our article on the topic. The short answer is that it's a great way to expand the tools for, and maximize the quality of, video capture on your current camera.

The Video Assist 4K is the larger of Blackmagic Design's current monitor/recorders. It features a 7", 1920 x 1200 pixel display and the ability to capture up to UHD/30p video in 10-bit 4:2:2 quality. It can accept video across HDMI or 6G-SDI inputs and offers outputs for when you want to include it in a more complex setup.

It's been on the market since April 2016 so it doesn't match the spec of the latest 4K/60p capable competitors, nor can it cope with the wider-screen DCI flavor of 4K but, through a series of firmware updates, Blackmagic has been adding features to this sub-$1000 monitor/recorder.

And, since it's likely to be a while before a majority of brands offer cameras capable of 4K/60p, its age doesn't weigh too heavily against it, unless you want to shoot the more cinema-like 1.85:1 DCI aspect ratio.

The Video Assist 4K can record in a variety of popular codecs, so that the files are immediately ready for use in Adobe Premiere, Apple Final Cut Pro or AVID Media Composer. All the Apple codecs and the 220 and HQX versions DNx are captured in up to 10-bit detail.

Apple codecs
  • ProRes Proxy
  • ProRes 422 LT
  • ProRes 422
  • ProRes 422 HQ

AVID codecs
(in either Quicktime or MXF wrapper)

HD Codecs
  • DNxHD 45
  • DNxHD 145
  • DNxHD 220x
4K Codecs
  • DNxHR LB
  • DNxHR SQ

It's also a fairly well-connected little beast, though, which makes it easy to hook up to most cameras.

Inputs Outputs
  • 1 x HDMI
  • 1 x 6G SDI
  • 1 x HDMI
  • 1 x 6G SDI
  • 2 x Mini XLR (balanced)
    with phantom power
  • Over HDMI
  • 3.5mm headphone socket

Batteries and storage

Unlike the Atomos recorders, which tend to use Sony L-series-style batteries and write to SSD drives, the Blackmagic uses Canon LP-E6 batteries and writes to SD cards. This use of more photographer-friendly formats has both advantages and disadvantages.

The obvious advantages are that, especially if you already shoot Canon, you may well already have the equipment you need to start shooting. No messing around with cradles to mount the SSD on your computer, you just use the same SD reader you use for stills photography.

The downside is that, until V60 and V90-rated SD cards become more common, even the most expensive U3 cards, for all their promises of transfer rates in the hundreds of MB/s, only guarantee to sustainably write at up to 30MB/s (240Mbps). If you're capturing video, it's this sustained write rate that you need to worry about and 4K can easily exceed this figure.

The Video Assist 4K uses common, Canon-style batteries and fast SD card, both of which you may already own and which are very widely available.

As a result, Blackmagic has to publish a list of SD cards it recommends for its higher frame rates and codecs. For most of the better ones, you'll need a UHS II, U3 card. Given the company's history of adding features to the Video Assist via firmware, the hope has to be that it's possible to offer proper support for V60 and V90 cards, but they wouldn't comment, when asked.

The downside of using the common LP-E6 batteries is that, although pretty powerful in comparison with other DSLR batteries, they're tiny compared to some of the huge L-series blocks you can get. Consequently, you'll need a handful of them if you're planning an extended shoot away from a power supply. I found I was getting 20-30 minutes of capture out of two fully charged batteries. The batteries can be hot-swapped while recording, in the unlikely event of you needing a single clip to last longer than that.

What's it like to use?

The first thing to get used to is how much size and weight shooting with any external recorder adds. The use of such a big screen immediately limits your ability to 'run and gun.' If you're just trying to grab some quick, on-the-move, on-the-fly footage, the Video Assist will slow you down. However, if you have the few extra moments to consider each shot, it increases the chances of you getting it right as well as increasing the quality of your footage.

if you have the few extra moments to consider each shot, it increases the chances of you getting it right

Its weight means that it's not easily mounted on your camera. There are plenty of hotshoe-to-tripod mount adapters available and, given the Video Assist's 928g (2lb) mass (with batteries), we'd recommend the use of the most sturdy ballhead-type adapter you can find. It's much happier if you have some kind of arm to attach it to your tripod or have your camera mounted in a rig, to which you can then add the Video Assist.

However, one of the benefits you gain for this weight is pretty rugged construction. The Video Assist's metal and rubber build doesn't promise any level of shockproofing, but our review unit survived an accidental fall onto pavement and has worked flawlessly since, suggesting it'll stand up to the rough-and-tumble of shooting in the real world.

Touchscreen interface

In terms of actual use, everything on the Video Assist is operated by touchscreen. It's pretty responsive, with only the slightest hint of lag and there are few enough options that you very quickly find your way around and learn it in no time at all.

The Video Assist gives you access to adjustable zebra highlight warnings as well as focus peaking, regardless of whether your camera offers these features.

However, the more you think about the way the interface works, the less sense it makes: three of the six button arrayed along the top of the main screen take you to the same menu, some options have left/right arrows with the Off option at the far left, others just have On and Off buttons, with Off on the right. The monitor and audio setup menu is accessed by pressing the 'Card' button. Even by the standard of camera menus, it feels like more and more has been added onto the system without any thought given to what a blank-sheet design would look like.

You can select what triggers recording from the main screen but toggling false color, peaking or zebras is an extra button-press away

Some of this may be down to my inexperience, of course. Perhaps more experienced users constantly need to change which input triggers recording or change codec mid shoot, but I find myself needing to toggle False Color on and off far more frequently, and I have to visit a separate menu page each time I want to do so. Revising this design would speed up operation of the Video Assist considerably.

It's also a little disappointing to see that you can only magnify the central portion of the scene: there's no way of moving the focused region around, which is awkward if your composition requires an off-center point of interest.

The Video Assist 4K can capture Log footage but apply a LUT to the image it displays. This GIF approximates the effect of applying the F-Log/F-Gamut -> WDR/BT 709 LUT available from Fujifilm.

Overall, though, the Video Assist is really easy to use, even for a novice like me. It was easy enough to upload a LUT using the desktop-based software, meaning I can shoot Log but with a comprehensible preview. Equally, once you get used to shooting with False Colors, it's awkward to live without them. Which brings us to...


In keeping with its history of adding features via firmware, Blackmagic Designs recently released the long-promised update that brings 'scopes to the Video Assist. This is a big deal, since scopes are a very powerful way of interpreting the tonal and color distribution in the footage you're capturing.

The Vectorscope shows you how the color in your image is distributed.

The latest update brings a luminance waveform, an RGB waveform/parade (though only represented in white, so a little hard to interpret) and a vectorscope.

The implementation is not great, however. All scopes are accessed by tapping the histogram at the lower left of the panel and they all take up the whole screen. Two tiny, tiny buttons inconsistent with the rest of the interface let you control over how the waveforms and video appear. The right-hand button brings up two sliders that adjust how bright the video feed is shown in the background and how bright the waves are displayed.

Waveform Waveform overlaid Video PiP

The second acts as a toggle to show the video feed as a small picture-in-picture window, but no way of showing the scopes themselves on anything but the full width of the screen, so you may find you have to toggle them on and off, rather than leaving them open to monitor as you shoot.

Despite this slightly rough-round-the-edges implementation, the addition of scopes is a significant addition to the Video Assist, especially as they're tools that are generally lacking from the cameras we tend to review. They're also a free upgrade to any existing owners and coincide with Blackmagic Designs offering a significant temporary price cut on the device, so we're not going to be too critical of the slightly imperfect integration.


For many people it won't be obvious why they should go out and spend $900 on an accessory that does something their camera tries to do already: preview and capture movies. However, for a certain kind of videography, the Video Assist makes life a lot easier (and the peace of mind it brings, in terms of knowing that your footage is going to be correctly shot is immense).

With a simple L-shaped bracket, you can make a relatively hand-holdable combination with some small cameras (though you'll need to think pretty hard about stabilization).

And, despite a couple of gripes about its operation, the Video Assist 4K is still a very easy-to-use, well specified device. It means that, for less than the cost of a new camera, you can maximize the quality of the footage you're capturing from your current one while also gaining access to a host of useful tools it almost certainly hasn't got.

In addition, shooting in formats such as ProRes and DNx means your footage is in and edit-friendly format, straight out of the recorder, potentially removing a time-consuming transcoding step from your workflow.

$900 isn't a trivial amount of money but, for a great many photographers, it's an amount they'd be happy to spend on a new lens. And, like a lens, it's a purchase that will probably outlive your current camera and work happily with whatever you're shooting in a few years time. Only the lack of 4K/60p or DCI 4K capture and the uncertainty over fast SD card support casts a doubt over its future-proof-ness.

What we like:

  • Captures the best of your camera's output
  • Adds hugely useful tools to support video capture
  • Durable build

What we don't:

  • Question mark over future SD card support
  • Increasingly convoluted interface