The COSMO C1 is the latest addition to the COSMO series. The key selling point for the COSMO C1 is that it is the industry’s first wireless video system to integrate a UVC (USB Video Capture) interface. This allows the COSMO C1 to offer a simplified solution for streaming and cloud-sharing video.

According to Hollyland, the COSMO C1 offers real-time video monitoring up to 1,000ft line-of-sight. It also incorporates boosted signal strength, better anti-interference capability in the 5.1GHz-5.8GHz frequency spectrum.
With a large array of ‘affordable’ wireless video transmission systems now flooding the market, Hollyland decided to make something that was a little different. The COSMO C1’s parlor trick is that Hollyland has integrated UVC (USB Video Capture). This enables you to use one USB-C cable to send up to 1080 60p video straight into your computer for direct live streaming. You don’t need to use any type of video capture device as the input will be recognized by your computer as a webcam source.

Build Quality

I have reviewed a lot of wireless video systems over the years, and the build quality of even the most budget-friendly options has continued to improve. The COSMO C1 is pretty solidly made. The exterior casing feels robust and I wouldn’t think it is likely to break if you dropped it.

The On/Off switch is reasonably solid and tactile, however, the scroll wheel feels a little bit on the cheap side. It moves around a little bit when you are using it and this could potentially be something that could break down the track.

Overall I think the COSMO C1 is well made and I think most people will be more than happy with the way it has been constructed.

Size & Weight

The COSMO C1 RX unit weighs 210g / 7.41oz. The TX unit weighs 214g / 7.55oz.

They are not tiny, but nor are they too big. I would say that they are around a similar size to other comparable SDI/HDMI systems.

Image Delay

Zero (or close to) image delay is one of the big reasons you pay more money for a higher-end system. Most high-end wireless video systems have basically zero latency, while a lot of the budget systems can have quite a lot of latency, especially those systems using HDMI. Hollyland claims that the COSMO C1 has a latency as low as 40ms. As the COSMO C1 uses SDI, in theory, the latency should be pretty low. So is it? Well, let’s find out.


I did some latency tests using the Kinefinity MAVO LF and output an SDI signal from the camera to the COSMO C1 TX. I then connected a monitor to the RX via SDI. I always use the same camera and monitor for my latency tests, so I know the testing criteria remain identical.

I measured the delay average over a series of three tests at 111ms. Even for a system at this price that latency is reasonably high, especially when using SDI. This far exceeded Hollyland’s claims of latency as low as 40ms. What you also need to keep in mind is this figure doesn’t include the latency between what is being filmed and what the camera is seeing.

As a comparison, the Accsoon CineEye 2S Pro Wireless Video Transmitter & Receiver when using SDI had an average latency of 77ms when viewing images on a monitor connected to the RX when the TX was set to High-Quality transmission. When I switched the TX to Speed I got a delay average over a series of three tests of 53ms. Above you can see a test using the exact same camera, monitor, and criteria as the Hollyland test.

You should never test image latency with just one camera so I did another test using the ARRI AMIRA. I outputted the signal from the AMIRA over SDI to the TX unit. I then hooked up the RX unit via SDI to a SmallHD monitor. I measured the delay average over a series of three tests at a whopping 143ms. This latency is only the latency between the TX and the RX units. It doesn’t include the latency between what is being filmed and what the camera is seeing.

Above you can see a test that clearly shows the latency between the object being filmed, the image on the ARRI AMIRA, and the image coming out of the RX unit to the SmallHD monitor. There is no way that Hollyland’s latency claim of down to 40ms is even vaguely close to being an accurate number. This is why we do actual tests during reviews. You should never believe marketing hype or claimed figures.

Author's Bio: 

Accsoon advocates providing high-quality, cost-effective film and television equipment for video enthusiasts and professional video workers. Its products are characterized by detailed design, ease of use, stability and intelligence, and are highly praised and favored by people in the industry.