Cinewhoops (cinematic tiny whoops) are getting extremely popular recently, every manufacturers are jumping into it. I will be checking out a few popular options in the market. The first one is going to be the BetaFPV 85X HD.
What is a Cinewhoop?
Cinewhoops are tiny little quadcopters with propeller guards, equipped with HD cameras that is capable of recording “cinematic” 1080p footage. With the compactness and safety of a tiny whoop, you can fly indoor, go through small gaps, or even fly around people without worrying too much. It allows you to fly at places you could never imagine on powerful 5″ racing drones.
First Batch of BetaFPV 85X HD
Good thing I didn’t jump into it too early, as apparently the first batch of the BetaFPV 85X HD had some sort of quality control issues with the ESC, and soldering jobs. BetaFPV assured me that they have since addressed the issues, and indeed I didn’t encounter these issues during my testing.
Where to Buy
- RMRC (US): http://bit.ly/2UKhB03
- GetFPV: http://bit.ly/2LJkCfy
- Banggood: http://bit.ly/2UIs7VO
- Amazon: https://amzn.to/2u8ooF8
- BetaFPV: https://betafpv.com/products/beta85x-whoop-quadcopter
You will also need some 3S 450mAh LiPo:
CNHL and Tattu are both good choices. Get the batteries with the “long stick” shape, it’s easier for mounting.
Specs and Features
Here are the components:
- F4 FC with MPU6000 Gyro (Target: OMNIBUSF4SD)
- ESC: BLHeli_32 16A ESC (burst 25A), supports DShot1200 (target: BETAFPV-16A-32bit)
- Motors: 1105 6000KV
- Propellers: EMAX Avan 2″ 4-Blade Props
- FPV & HD Camera: CADDX Turtle V2
- Receiver Options: Frsky XM+ / DSMX / Futaba S-FHSS / Flysky / TBS Crossfire
- VTX: 48ch, 200mW, Supports SmartAudio
- Lumenier AXII antenna
The weight of the 85X HD is 75g… heavier than the 58g they claim on the product page. Maybe they are referring to the cheaper version of the 85X with EOS2 camera?
Motor to motor distance is 85mm (the name gave it away). It’s slightly bigger than its brother the 75X Pro.
The selection of receiver options is simply awesome, covering almost all popular radio systems in FPV! Even the pricey Crossfire is available! I do however, wish they could add R9MM to the list in the future.
My test unit came with a Frsky XM+ FCC receiver. If you are also getting the XM+, make sure to pick the right firmware (FCC or LBT). But don’t worry if you picked the wrong one, you can still flash the receiver to the firmware you want.
Closer Look at the BetaFPV 85X HD Whoop
The frame is made from the same kind of flexible and crash resistant plastic as other Tiny whoops. But the blue canopy is made of much harder and thicker injection molded plastic, it doesn’t bend at all upon impact, This provides much better protection for the Caddx Turtle HD camera.
The first thing i noticed was that the camera lens sticking out of the canopy a tiny bit. Perhaps a little more extrusion on the canopy around the lens can provide better protection in crashes.
The camera tilt angle seems to be fixed at around 35 degrees, I couldn’t adjust it even after loosening the screws on both sides. Luckily the camera has quite a wide FOV (155°), I can see the horizon well when hovering, so it’s totally flyable at low speed.
You can start and stop the HD recording on the Turtle by pressing the push button under the lens (through the hole in the canopy).
The SD card slot for the Turtle can be accessed from the back under the VTX.
I really think the Turtle has a serious fundamental design flaw, there is nothing to stop the SD card from ejecting in crashes! It’s not BetaFPV’s fault, but I think a work around could be implemented in the design of the canopy. For now, maybe I’d just stick a piece of tape on the slot.
Moving to the back, there is an unbranded 200mW VTX sticking out. Perhaps the design is not the best in terms of aesthetics, but it’s certainly very practical! Firstly, you can easily press the button to change channels and power. Secondly, it’s great for cooling!
The VTX power can be switched between 0mW (pitmode), 25mW and 200mW. It even has SmartAudio setup out of the box, so you can change channels and power in Betaflight OSD. Very handy.
The VTX antenna is a Lumenier AXII that is customized for BetaFPV. Great VTX and antennas, but I am not a fan of how the antenna is mounted. I will show you a better way in the setup section.
There are four RGB LED’s at the rear, a nice touch by BetaFPV. It’s configured out of the box to display “Arm status” and “low voltage warning”. You can make it do other things as well, see my tutorials about setting up RGB LED in Betaflight.
This quads supports 3S Lipo through the XT30 connector. Some people tried 4S and burnt theirs so I wouldn’t recommend it. There is no point running 2S either. If you want less power, just limit your max throttle!
The Beta 85X HD comes with a battery strap and rubber pads installed.
The motors are 1105 6000KV running 2″ quad-blade props.
The motors are connected to the 4in1 ESC through 3-pin connectors. This makes swapping or troubleshooting motors much easier because you don’t have to solder.
The motor mounts are 9x9mm pattern. They are only using two screws per motor for weight saving. Mind you, they didn’t use any threadlock! I guess you should check yours and do this yourself.
Removing the battery straps reveals the receiver, a Frsky XM+. As you can see the antennas are just left hanging around freely. Is this intentional? Or did they forget? I don’t know, I only know this is asking for trouble, these antennas will get damaged sooner or later. I will show you how I mount them in the setup section.
Powering on with LiPo, and it didn’t blow up! Good sign :)
Taking it Apart!
Let’s take it apart and see what’s inside. There are only two screws holding down the canopy, on the left and right sides.
The wiring is pretty basic.
The canopy houses the Caddx Turtle V2, lifting that you will find three wires between the camera and the FC (5V, ground and video in). There are four black wires going to the VTX (5V, ground, video out, and smartaudio).
Here is the pinout diagram of the FC:
Two long “cables” from the Turtle are hanging freely in there. The connector is for connecting up to a “joystick” for changing camera settings, the black round thing is the mic for the camera.
Not sure if that’s really a good idea to leave them loose like this, they can be hitting the flight controller constantly during flight, that could have an effect on the gyro. I would probably secure them with a bit of hot glue or tape at least.
The FC and ESC are built on separate boards, connected by header pins (can’t be removed).
Here is the bottom view of the 4in1 ESC.
Setting Up For First Flight
The quad came pre-flashed with Betaflight 3.5.0, and PID is “tuned” out of the box.
If you want to update Betaflight, be careful! The 85X is running “props out” (motor rotations are reversed). When you flash Betaflight, settings might be reset back to default and your quad will flip over at take off. Just remember to re-enable “reverse motor rotation” in the Configuration tab. Props out is better for tiny whoops as it improves flight performance.
Binding RX to the Taranis was effortless: flip over the quad, and the bind button is right there on the receiver! However I do recommend putting the RX in transparent heatshrink to avoid shorts since it’s on the bottom. Use double-sided foam tape so it doesn’t wiggle around which is bad for solder joints and antenna connections.
I had to change Channel Map in Betaflight to Default (AETR) (you might or might not need to change, confirm in Receiver tab). Please note that, with the XM+, Channel 16 (AUX12) sends RSSI data back to the FC, you can display it on your OSD if you want.
Change to my rates and expos (RC rate 1.3, Super Rate 0.68, Expo 0.24).
There is no buzzer onboard, so it’s important to setup ESC beacon, so you can still find it when you crash under the sofa, or in bushes.
- Assign a switch to beeper mode
- Set beeper_dshot_beacon_tone = 3
I wasn’t very happy with how the VTX antenna was mounted (pointing backward at the horizon). When you are flying away from yourself, you are basically giving yourself the worst possible signal.
I recommend mounting it at 45-60 degree up, so when you are flying forward (the quad is tilted at 30-45 degree), your antenna is always straight up pointing at the sky, giving you the best possible signal.
RX antennas need better mounting as well. Same principle applies here, one antenna is pointing up at an angle, the other you can point it at any direction you want horizontally.
ESC settings all seem to be default (apart from motor spin direction). I might play around with PWM frequency and motor timing see if there is any room for improvement. As for now I increased beacon strength for louder “buzzer”, and uploaded custom startup tone.
Further Review Coming Soon
I have been testing this quad with 3S 450mAh LiPo. Out of the box, it flies very smooth without any further tuning, and the quad is very controllable. It’s certainly more powerful than a tiny whoop even though it’s way heavier. The throttle curve and response are very different, and it takes a few flight to get used. But once you overcome that, it can pull off some very precise flying just like a whoop.
Efficiency is very impressive. I am able to get 4:00 – 4:30 minutes of flight times (indoor). If I fly a bit slower I can sometimes even get over 5 minutes.
Here is some footage flying outdoor.