How To perfectly balance a Black Magic 4k on a Zhiyun Crane 2
This is about ten-minute read where we dive into all the dos and dons approaching a gimbal and balancing. If you’re interested in how to balance your gimbal as fast as possible jump to the actual balance process section towards the end.
When the P4K first hit customers hands, there was a borderline backlash in the forums. Proud owners of their new camera were disappointed to find out they couldn’t mount their cameras onto their Crane 2 gimbals. At first glance, it seems borderline irrelevant to even want to balance such a powerful camera on a gimbal that has been updated already to its big brother, the Crane Lab 3, but there are a lot of advantages to being able to take up less space and carry less weight (especially if you don’t need the extra weight).
During IBC 2019 we were walking around with two P4Ks: an A Cam on a tripod and a B Cam on a gimbal. We were stopped countless times by the many visitors at the convention either asking us how we were able to mount the camera in the first place, or appreciating the idea. The B Cam is my personal rig for a lot of smaller projects that don’t necessarily have the budget or time to outfit the camera with all the more fun bells and whistles. In these more time frugal conditions, this set up has saved my butt more times than I can count.
What are we balancing?
Before we get to balancing, let’s talk about what’s on the camera and why.
In short, not a lot. Even though the gimbal “technically” supports 3.2 kg (about 7 pounds in American) you are limited by where the weight actually is and the redistribution of the weight using the arms. Then you have the physical limitation of the arm. Sometimes offsetting the weight means you might hit a part of the gimbal. For example, if you want to mount a front-heavy lens like the Sigma 20 f/1.4 (a grossly front heavy lens) you’re going to need to add weight to the back of the camera. You obviously can’t mount a monitor, as the added height would
likely definitely hit the arm of the Roll Axis. You can try offsetting the weight with counterweights, however, if you need more than about 200 grams, you risk hitting scraping the bottom of the Pan Axis.
The key is to keep it light. For almost the entirety of the show, we mounted native MFT lenses which are super compact and lightweight and remove the bulkiness of adapters, which attach to heavier lenses. We switched between the Panasonic Leica 12mm 1.4, and the Olympus 25mm 1.2 Zuiko. Two fast affordable lenses that weigh next to nothing. The Zuiko is about as heavy as the Canon 85 1.8.
Next is power. Since the Black Magic has an incredible battery there’s no need to address this. NOT.
That being said, I think people tend to lose control when it comes to power solutions. It seems like they forgot about the days when we were shooting video on 5d mark ii and we had to switch batteries every two hours. Honestly, for the most part, you just need a little more juice. You don’t need a single battery to get you through the day. I opted for an NP-F battery plate. You have two options from here, dummy battery and Weipu connector.
For the life of me, I don’t know why you would buy a dummy battery, its an extra point of failure and it leaves the battery chamber open. Shove a REAL battery in there, and opt for the Weipu connector. The battery indicator will be labeled AC for as long as your Sony battery is alive, and when it dies you can begin to count the minutes with the voltage indicator. Fun fact, this method actually charges your LP battery inside, so even if you start to burn through your LP-e6 battery and then swap the LP, no need to change the internal battery as it will begin to charge the battery anyway.
I have 15 small NP-F550 batteries. They’re small, cheap super lightweight and make for a quick hot-swap without removing the camera for the gimbal. (they also help offset the weight if you mount it like we did on the right side of the camera.
As for the mounting. I’ve seen many people jump straight for the offset plate without realizing that they actually can mount the camera directly to the gimbal so long as you have a cage. For this entire method to work, you need the mounting holes of the cage anyway so it’s crucial to the process. It may seem silly to advocate 1 cm, but you can gain a little extra weight if you don’t use the furthest hole to the right on the bottom of the P4K, instead use penultimate hole to the right. When balancing a camera on a gimbal, its best to not go to the extremes of the arms as the gimbal becomes less stable.
The actual balance process
Lastly, the balancing. The method I use is similar to the implementation that Zhiyun has included in the models proceeding the crane 2, where you can lock the axis to not only transport but to balance. This is nice if you’re starting out, but you’re a professional, so you want to get that stuff done as quickly as possible.
Start by finding the center of gravity of your camera, it comes with time where you can nail on the first try exactly where to screw it in exactly on the plate. In an ideal world, though, you would have mounted it with plenty of room to travel on the sled so that switching between lenses is easy and requires little adjustments. For example, I’ve found that mounting between 2 and 3 (the numbering on the back of the plate) I can mount my a7III and MC11 with a 14mm Samyang, a 50 1.4 sigma, a 24 1.4 sigma, and an 85 1.8, with only tiny adjustments to the gimbal not the plate and no additional counterweights.
Once you have located the right placement on the plate, its time to balance. Run through a super rough estimate of where things need to be (start by doing just the sled, roll and tilt). It’s fine for it to go whack while you’re running the first round. Start from the sled while holding the tilt axis, then hold the roll axis and adjust the tilt, then adjust the roll axis. Once round one is done, you’ll find that you need tiny pushes to get yourself up and running so that you can get that gimbal balanced in under a minute.
I say in the video people screw up the pan axis a lot, or forget, or don’t adjust it between lenses. It will add stability, especially in more demanding shots! DO NOT FORGET THE PAN Axis. The ideal way to address it is by holding the gimbal out horizontally and pointing the lens to the sky. The pan arm should stay parallel to the floor. But how cumbersome does that sound? Instead, just tilt your gimbal slightly using ⅔ legs of the included tripod and wait for it to stop moving when you force it to a 45-degree angle. If you have time during initial set up, you can do the “proper” check and fine-tune, but you’ll find that the result is VERY close to perfect.
Adam Frimer is a Guinness World Record holder, producer, and DOP based in Tel-Aviv, Israel. Adam owns a production company that specializes in corporate marketing and brand strategy. His videos have collectively hit over a quarter billion views