The DJI Focus
is a specialist piece of kit, aimed at professional users looking to capture true cinematic shots by smoothly pulling or racking focus mid shot. It can be used on both ground and aerial platforms such as the DJI Inspire Pro
or on the DJI Ronin
. In this article I give my initial DJI Focus review
and talk you through how it works and what roles it can play in a professional film production. I've also included a short video clip of the focus in action
What's In the Box
- The DJI Focus remote controller
- 3 x Marking Rings
- Neck strap
- CAN-Bus data link cable
- Micro USB cable
- User Manual
Aesthetics - DJI Focus Build Quality
What was immediately apparent was the shier weight of the remote control, weighing in at just over 750 grams it. But with the weight comes a good build quality. It feels like a solid unit, more robust than any other DJI piece of equipment I've used which bodes well for being an investment that will be able handle regular use and take bit of a beating.
The neck strap provided is padded and wide enough to have round your neck with the remote control attached, comfortably for long periods of time.
What Does the DJI Focus Do?
The DJI Focus allows you to smoothly change focus by rotating the wheel on the front of the controller. Changing focus will be most noticeable when you are shooting with a low f-stop (e.g. f/2.8), giving you a shallow depth.
Before I get into the details of what it's capable of, lets quickly outline the differences between the pulling focus and racking focus and what kind of situations they may be used in.
Pulling Focus - Keeping a subject in focus as it's distance from the camera varies. For example if you are filming someone walking toward the camera you will want to smoothly adjust the focus so that the person stays in focus throughout the shot.
Racking Focus - Switching between two focus points. For example if you quickly go from being focused on raindrops rolling down a window in the foreground to focusing on what is outside in the background, this would be a rack focus.
On the side of the focus wheel you can set hard start and stop points using two adjustable thumbscrews that limit the focus wheels travel. This is perfect for when you want to rack focus accurately and consistently (assuming that the camera and subject stay at the same distance from each other).
You also have the option to digitally switch between focus points by pressing the A, B or C buttons. Each of these focus points can be customized and fine tuned.
The dial in the centre of the wheel allows you to adjust the resistance when turning the wheel so that you can choose how sensitive the wheel is depending on how slow/smooth you want the change in focus to be.
Setting up the DJI Focus with the DJI Inspire 1 Pro
I was pleasantly surprised at how easy it was to set up out of the box. All you have to do is hook up the data link cable between the DJI Focus and the camera operators remote control using the data port on the DJI Focus and the CAN-Bus port on the back of the camera operators controller.
Once you have powered up the Inspire, Focus and both controllers, the focus controller will automatically be detected
and will work straight away. No pairing or calibration needed.
It's worth noting that you will most likely have to be a 3 person setup when using the DJI Focus (pilot, camera operator and focus puller) and performing dynamic shots. However, the camera is not required to move, the cam-op can then assume the role of the focus puller.
Marking Rings for Focus Measuring
Traditional, focus pullers (people who adjust a cameras focus on a film shoot) wrote various distances around a ring that went around the focus wheel so that he/she can change the focus based on the actual distance of the subject in relation to the camera rather than relying on end points or focus peaking technology. DJI have catered for this technique by including 3 removable white marking rings so that you can have a different ring for different lenses as different lenses have different focusing distances.
Underneath the marking ring is an LED light which back lights the ring, making your markings easy to read if you're on set and there isn't much ambient light.
The DJI Focus can also double as an aperture control ring which was news to me as I didn't see it advertised anywhere but it's true! You can change the function of the focus wheel to control the aperture ring through the settings menu on the OLED screen.
DJI Focus Battery Life
Although I have not tested it, DJI are claiming it will last for 14 hours from a full charge which would usually be more than enough for a full days filming. The 1700mah Lithium Ion battery is removable though so perhaps DJI will release extra batteries in the future.
Mounting To Other Devices
The DJI Focus has a rosette mount,
which is a universal mount, allowing you to attach it to third party devices (e.g. a monitor or simply onto a tripod or magic arm).
Word of Warning - Fragile Connector
I found this out the hard way so you now that you have read this, hopefully you can learn from my mistake... Do not force the data plug into the remote control. It will clip in smoothly if you have it lined up. If they're not lined up and it's not going in, don't force or twist it, you will bend the connector pins. Simply pull it out and re-align.
DJI Focus in action
The shots above were all shot with an aperture of f/1.8 to get that shallow depth of field to exaggerate the focus.
We would have had a third person to control the focus but we couldn't get anyone in so the camera operator stood up to the plate and doubled as the focus puller.
We tested the system with both the Olympus 45mm and the DJI 15mm that comes as stock with the DJI Inspire Pro.
In an ideal world, we would have shot with only the 45mm as this would give the most dramatic results but it was rather windy on the day so shooting with the 45mm and no camera operator was difficult.
Conclusion to the DJI Focus Review
It seems like a great bit of kit, with a solid build and very easy to set up. The weight of it is a slight cause for concern if you are using it for long periods of time but the neck strap will help a lot with this.
As to its place in an aerial cinematographers kit list... I'm not convinced unless you have a highly experienced focus puller. Having said that, I can defiantly see it being a great tool to have for ground work on rigs such as the DJI Ronin
If you're interested in purchasing the DJI Focus we now have them in stock, or if you'd like to talk with us further about it, drop us an email
or call us today on 01737 457404.