Remote record triggering for Blackmagic Pocket 4k

For the past 6 months or so, I’ve been filming all of my video projects on the Pocket 4k from Blackmagic. It is an absolute joy to use so much so that my 1DC is starting to whine for attention. There is only one thing that has become an inconvenience. It is so minor that I almost feel bad for kind of complaining about it. Almost.

When I first built out my system, I picked up the Ikan PDMovie wireless follow focus system. It’s small, self-contained and works great with my lenses. It fit into my cage setup and I had perfect reach with my left thumb. My only gripe is that the focus motor’s battery life was pretty bad. Not as bad as the Pocket 4k but close. Carrying multiple batteries, as always, is the easy fix.

Where things got slightly inconvenient is when the camera was mounted on a gimbal. With the Ronin-S, I use the DJI follow focus motor which is seamless with the whole setup. Focus wheel is responsive and the motor has no problem driving the lenses. The issue came with starting and stopping the recording. Again, not a huge deal but after awhile running around with the gimbal setup, reaching with one hand to get the record button can get a wee bit shaky. So, I started hunting for a solution to a remote record trigger.

The Pocket 4k does not have a LANC interface which rules out almost every solution currently out there. However, that isn’t a big deal as Blackmagic has an SDK available for 3rd parties to build their extensions to the camera platform whether that be the URSA, Pocket 4k, Pocket 6k or any of their hardware solutions. As someone who was a software engineer in a past life, I appreciate that immensely even if I’ll never write another line of code in my life.

With a little digging, I came across a post on the Blackmagic forum. It spoke about using the Tilta Nucleus Nano follow focus system with a hardware extension that would connect to the Pocket 4k via Bluetooth to trigger recording. Sweet baby kittens! Exactly what I was hoping to find. The post pointed me over to the BLE4K website which was going to handle the purchasing and distribution for the Bluetooth hardware.

The Nucleus Nano arrived a few days before the BLE4K hardware and I find it much better than the PDMovie system. The focus motor is powered via USB, not a battery, which means I can use a D-Tap to USB cable off a v-mount battery. Or I can use my small Jackery battery mounted to the cage. Or I can use the power ports on the Ronin-S. The focus wheel is powered from a rechargeable battery and the life, so far, has been very good.

The other day I tried setting it all up but, for whatever reason, I couldn’t find the wifi being broadcasted from the BLE4K unit. I tried again this afternoon and everything popped up. Here is a pic of all the components.


The setup is pretty painless. The focus motor has a 3.5mm jack next to the USB port. The BLE4K gets plugged in first then power to the motor. On the Pocket 4k, go to the last page of the Setup menu and turn on Bluetooth. I found the BLE4K network with my phone and once connected, the configuration popped right up.


Once in the configuration, you tap ‘Pair Camera’ then ‘Connect’. The Pocket 4k responds with a Bluetooth code. Back in the BLE4K configuration, you tap ‘Pairing’ and enter the code. The BLE4K is now paired to the camera and auto-connects from here on out.

Now, the fun part. Hitting record on the focus wheel triggers the camera. Woohoo!

Super stoked on how well this works. Now, time to break out all the cage pieces and adapters to make it all fit on the cage and the Ronin…