There are instances when installing a full-sized GoPro on your FPV drone may not be viable due to its hefty weight. In such scenarios, the Hawkeye Thumb 4K Camera could be the perfect fit for your needs. Featuring 4K resolution and built-in gyro for image stabilization, this camera comes at a notably attractive price. Positioned as an alternative to the renowned Runcam Thumb Pro, the Hawkeye Thumb 4K Camera brings its own distinctive features to the table. In this review, I’ll be sharing my experiences insights about this product.
Table of Contents
Where to Buy?
You can purchase the Hawkeye Thumb 4K camera from these vendors:
The camera comes in relatively simple packaging. The box contents include the following accessories:
- A concise instruction leaflet
- 3 video output cables (USB-C to 3.5mm headphone jack, available in red and black, along with a 3.5mm female to RCA)
- 3 power cables compatible with 3S, 4S, and 6S batteries
- An OSD programmer board
- A set of stickers in Chinese
Please note that the package does not include an SD card. You can purchase one here: https://oscarliang.com/sd-cards-fpv/#GoPro-and-Other-HD-Cameras-4K-Videos. Ensure the SD card you choose has a capacity ranging from 8GB to 64GB.
The Hawkeye Thumb 4K camera packs some impressive features. Here’s a rundown of the key specifications:
- Image Sensor: SONY 12MP
- Field of View (FOV): 170°
- 4K 50FPS (16:9, without gyro)
- 4K 30FPS (16:9)
- 2.5K 50/30FPS (4:3)
- 2.5K 50FPS (16:9)
- 1080P 50/30FPS
- Video Format/Encoding: .mp4/H.265
- Bitrate at 2.5K 50FPS: 30-35Mbps
- Supports micro SD Card, ranging from 8GB to 64GB (U1 or higher).
- Connector: USB-C
- Video Output: PAL/NTSC
- Input Voltage: DC 5-23V
- Dimensions: 49×22×13.5mm
15.5g15.8g (16.5g includes UV filter)
Initial Impressions and Design
Upon unboxing, one of the first things you’ll notice about the Hawkeye Thumb 4K is how it resembles the Runcam Thumb Pro. The form factor, shape, and even weight (a slight 16.5g with a UV/ND filter) are similar. A distinctive advantage of the Hawkeye Thumb 4K, however, is the lack of need for an extra mount, making for a potentially lighter setup than its Runcam counterpart.
On the front, you’ll find a removable UV lens serving as a protector. Additionally, this lens can be replaced with an ND filter (just twist to remove it). Please note that the ND filter isn’t included in the package but can be bought separately; only ND16 is currently available.
Next to the lens, you’ll find a push button for recording, stopping, and changing modes. There’s also a helpful LED indicator that changes color to show the current camera mode.
- Red + Blue (creating a purple hue): 4K/2.5K@50fps (4:3)
- Blue: 2.5K@50fps R1080P@50fps
- LED Off: 4K@30fps
On one side of the camera, there’s a USB-C connector for transferring video files to your computer, and it can be also used for video output. This is a welcome improvement from the outdated micro-USB connector found in the Runcam Thumb Pro.
On the opposing side, you’ll find the SD card slot, secured by a thoughtful retention clip to prevent any accidental ejections during crashes.
To reduce weight and cost, there’s no screen on the camera. To change camera settings, connect the camera’s video out to a monitor or FPV goggles via AV input and use the OSD joystick board to navigate the menu. In addition to this, a built-in playback feature allows for flight reviews in the field. You can adjust various parameters such as resolution, exposure, WDR, sharpness, contrast, ISO, and FOV within the menu. Upside-down installation image rotation, auto-recording, and audio on/off can also be configured via the OSD menu system.
This camera is compatible with most analog FPV goggles that have a headphone jack AV input, like Fatshark and Orqa. You can directly connect the “DJI”-labeled red USB – AV cable to the Goggles V2 video-in port (this also works for Orqa).
With its low latency, the Hawkeye Thumb 4K camera can be connected to a VTX for FPV flights via the video-out pin in the 4-pin connector on the back.
In order to minimize weight, the housing is also minimalist, which unfortunately makes the camera more prone to water, dust, and physical damage.
Another intriguing design feature is the integration of the plastic mounting bracket (M3 holes) as part of the camera. This could be a love-it-or-hate-it feature, depending on how you plan to use the camera. Personally, I find it quite convenient as it eliminates the need for 3D-printing a mount. It allows for direct mounting in many BNF (bind and fly) drones, saving you the extra hassle.
Using Hawkeye Thumb As FPV Camera
One of the key selling points of the Hawkeye Thumb 4K is its potential function as an FPV camera. Thanks to the video-out pin located at the back of the camera, it can be wired directly to an analog video transmitter, transforming it into an analog FPV camera. This functionality distinguishes the Hawkeye Thumb from other thumb-sized action cameras, including the Runcam Thumb Pro, Caddx Peanut, and the Insta360 GO 3.
This feature is particularly beneficial for those looking to save weight on their drone while still capturing HD footage. By using the Hawkeye Thumb as an FPV camera, you can avoid the need for two separate cameras. Furthermore, the camera’s wide voltage range of 5V to 23V (as opposed to Runcam’s limiting 5V input) simplifies wiring and offers more flexibility in the build process.
However, there are a few drawbacks to be aware of. Firstly, Hawkeye doesn’t supply the required wiring for AV out in the package, it may require some DIY improvisation. Secondly, the AV out has a 16:9 aspect ratio, which could result in distorted image if your display or goggles only support 4:3.
I found the latency not as high as I’d initially expected, but it was still more than a typical FPV camera. Finally, the field of view in FPV is smaller than that in the HD footage and seemed more zoomed in. It didn’t pose a significant problem when going through small gaps but did add a level of difficulty compared to using a regular FPV camera.
Given these reasons, I might hesitate to use the Hawkeye Thumb as an FPV camera on a racing quad, but it should perform just fine on a fixed-wing aircraft.
Powering the Camera
It’s impressive how HawkeyeFPV made a 16g camera that can record 4K video with gyro data. Unfortunately, the lightweight design has a compromise. Without a built-in battery, the Hawkeye 4K Thumb can’t be used as a standalone action camera like the Insta360 GO 3. This means extra wiring is required to power the camera from a battery or voltage regulator.
The camera supports 5-23V DC inputs, which makes it convenient to power it directly from your drone’s main battery. Included in the package are power cables with varying size balance connectors designed for 3S, 4S, and 6S LiPo batteries, which can be directly attached to a battery’s balance connector.
While the camera can be powered directly from a 2S to 5S battery, a 6S battery exceeds its voltage tolerance. But what about the provided 6S cable? Here lies an ingenious design – only the 1st and 5th pins in the connector are present. Thus, when connected, it’s providing 4S voltage to the camera. You might wonder if this would lead to cell unbalance, but in practice, the camera draws such a small amount of power compared to your drone that any unbalance would be insignificant unless the camera remains plugged in for a lengthy period of time on the ground.
Operating the Hawkeye Thumb 4K camera is straightforward and intuitive.
Upon powering up the camera, starting and stopping the recording is as simple as pressing a button. The camera gives you audible feedback, indicating whether it’s recording or not.
Changing settings is also a breeze. All you need to do is connect the camera to a display or FPV goggles using the provided video out cable, attach the joystick board, and power on the camera. A couple of presses of the LEFT button and you’ll find yourself navigating through the camera’s menu. This user-friendly interface truly enhances the overall user experience.
Gyroflow is an open-source video stabilization tool that utilizes gyro data for precise motion compensation. This technology allows for gimbal-like stabilization without any significant weight penalties.
One standout feature of the Hawkeye 4K Thumb Camera is its ability to save gyro data while recording. This feature makes this camera fully compatible with Gyroflow, taking your flight footage to new levels of smoothness.
To understand how Gyroflow works, you can refer to my guide. Although it’s written with a different camera in mind, it provides a rough overview of how Gyroflow works.
Here are my recommended settings for Gyroflow with this camera:
- Search for lens profile (Hawkeye Thumb 2.5K 50P)
- Sync Advanced Settings:
- Sync Search Size: 5.0s
- Max Sync Point: 3
- Time to analyse per sync point: 3.00s
- Offset Method: Essential Matrix
- The rest default
My Preferred Video Settings
When it comes to video settings on the Hawkeye 4K Thumb Camera, I’ve found that 2.5K at 50FPS with a 4:3 aspect ratio yields the best results for me. I tend to avoid 4K mainly because it doesn’t support 4:3, and the gyro recording is only available at a slower 30fps. The advantage of using the full sensor image (4:3 for this camera) is that it offers a wider field of view (FOV) than the 16:9 aspect ratio.
Without an ND filter, the default settings provide decent results in my experience. However, it could be beneficial to reduce the contrast and sharpness settings, then later increase it again to your liking in video editor.
If you choose to use an ND16 filter, you should set your shutter speed to a fixed value (e.g., 1/120 for 50fps or 1/60 for 30fps). Aim to set the ISO as low as possible without underexposing your footage. For post-production color grading, set the color to ‘flat’. If you don’t intend to color grade, you can leave the color settings at their default values.
For insights into how to use ND filters effectively, you can refer to my tutorial here: https://oscarliang.com/nd-filter-fpv/
This article explains why I choose these camera settings (it’s written for GoPro but the same principles apply to most action cameras): https://oscarliang.com/gopro-settings-fpv/
Image and Audio Quality
Here’s the footage and how it compares to DJI O3. It’s filmed using Flyfish 3.5″ quad I recently built.
The Hawkeye Thumb 4K camera offers acceptable performance in terms of image quality. Although it doesn’t reach the level of top-tier action cameras such as GoPro, it still offers reasonable value for the price. What truly sets this camera apart is its stabilization capabilities, which are surprisingly good for such an affordable camera.
There’s a tiny bit of ‘jello’ in the footage, but this is not seen in the O3, leading me to suspect that it’s the TPU mount rather than the camera or the drone causing this issue. It’s possible that TPU is too flexible, and using stiffer materials such as PLA or PETG might provide a better result.
The camera’s wide dynamic range is lacking. Although the Hawkeye Thumb 4K tends to offer great details in the shadows, brighter areas like the sky can often get blown out. After stabilization with Gyroflow, the field of view is also smaller than that of the O3, but it’s still quite acceptable for a budget camera.
Despite using the H.265 codec, the video bitrate of around 30-35Mbps doesn’t produce a highly detailed image. You can spot a noticeable difference in quality between 2.5K and 1080p resolutions, but the image quality between 4K and 2.5K is largely similar.
As for the audio quality, there’s quite a lot left to be desired. The built-in microphone picks up too much wind noise, making the audio unsuitable for flying. The captured audio is also exceedingly loud, even with a volume reduction of about 20dB in post, and it’s still quite loud and rather unpleasant to listen to.
The Hawkeye Thumb 4K also offers a webcam mode, adding to its versatility. To switch to the “Webcam” mode, press and hold the button for about 8 seconds. Once in this mode, the Windows OS will automatically recognize the camera and select a video resolution of 1080p at 30fps. This feature can be handy for users who need a portable and adaptable webcam solution.
How To Update Firmware
Here are the steps to follow for a firmware upgrade:
- Delete all the files and folders in the micro SD card.
- Download the latest Thumb 4K firmware. This will be a *.bin file which you should then copy to your micro SD card.
- Insert the SD card back into the Hawkeye Thumb 4K camera.
- Power on the camera. The firmware update process will commence automatically. You will know the process is underway as the LED will continuously flash.
- Once the firmware update is complete, the LED will stop flashing.
- The camera will then reboot itself, and your updated firmware will be operational. Please ensure not to power off the camera during the update process as it might cause damage to the device.
The Hawkeye Thumb 4K is an affordable and functional choice for FPV drone pilots on a budget. It offers an impressive list of features and performance that is commendable for its price range. Despite a few minor compromises, it delivers good value and emerges as a worthy option in the lightweight FPV camera category.
For those interested in purchasing the Hawkeye Thumb 4K camera, it’s available at these vendors:
While the Hawkeye Thumb is cheaper than the RunCam Thumb Pro, the latter does offer marginally better image quality. However, whether this slight improvement is worth the extra cost is up for debate. For those whose primary focus is superior image quality, it might be more worthwhile to consider investing in more expensive camera options from brands like Insta360, DJI, or GoPro. For a comprehensive review of action cameras for FPV drones, you can check out my roundup at: https://oscarliang.com/action-camera/