Logitech has recently launched the Logitech HD Pro Webcam C920 webcam, and this one is of particular interest to me because the H.264 video compression is done in the camera itself. You heard that right, we are talking about built-in hardware compression here. If you are not familiar with how this works, usually, webcam capture video and an uncompressed stream is sent to the computer, where the main processor (CPU) performs the video compression before it is sent by a software like Skype. The compression can vary from a video-call software to another, but the principle stays the same. By having the camera perform the hardware, it is possible to have excellent video quality, even on a mildly powerful computer.Context
We use Skype quite a bit in the office, so we decided to put the camera to the test to see if it lives up to the hype. Note that to take advantage of the 1080p video streaming in Skype, one needs to install Skype 5.7 (beta for now) or above. To test this, I have decided to try the Logitech HD Pro Webcam C920 on my old Macbook Air (Core 2 Duo + 4GB), as it is not a powerful computer. I was really curious to see how the camera would perform.
Results
The result was very interesting: both the image quality and the fluidity of the Logitech HD Pro Webcam C920was noticeably higher than even the Logitech HD Pro Webcam C910 which is just a notch below, and the difference is particularly noticeable when compared to the older Logitech Quickcam Pro 9000 that was one of the best webcams just a couple of years ago. Here are the screenshots taken from my desk, and I have uploaded the full-size images on our Ubergizmo Flickr account as the 640 pixels wide photos don’t give a real sense of what it looks like.
Skype screenshot with the Logitech Quickcam Pro 9000
Skype screenshot with the Logitech HD Pro Webcam C910, you may notice the “sharpening” filter
Skype screenshot with the Logitech HD Pro Webcam C920
Above are screenshots from Skype Calls where I show my desk. They are a good base to illustrate the differences between the few Logitech webcams that we have around. It is clear that things have changed a lot since the QuickCam Pro 9000 which great when it came out, but even when compared to the recent Logitech HD Pro Webcam C910, the difference is noticeable in full screen. If you have a small display or use Skype in a window, this won’t matter as much to you. I personally like to video-call in full screen, so every little detail is blown up.
Update 12/16/2012: it’s been a while, but I see in the comments that the screenshots provided below aren’t enough to form a definitive opinion. It’s true that Skype probably introduces too much interference and the image reduction to fit the site’s 640 pixels width content may remove too much information. At Ubergizmo, we never want to leave people in the cold, so we came back with a better test setup which consist in a controlled lighting environment and crops of the photos captured with the webcam at their highest resolution. Here it is: Logitech C920 vs. B910 (if you want to know what the difference between C and B series, read this thread @ Logitech. Basically, its’ the software)
shot in bright lighting conditions
shot in low-light conditions
The Logitech C920 wins pretty clearly in these shots, and I’m uploading the full-size photos and movies to Flickr, just in case, you want to have a closer look at those. Enjoy!
CPU Utilization
The CPU utilization is hard to measure because if the image is moving, that changes the bitrate of the camera, and even though there is hardware compression, the dataflow still changes enormously. In any case, I have not seen any practical low-CPU utilization with the Logitech HD Pro Webcam C920. I can believe that for the same quality it may use less resources, but I can’t tell, because I can’t tweak the quality to compare apples-to-apples. So, if you have a slow PC, you can expect better compression and better image quality, but don’t expect low CPU usage – in the Macbook Air 11″ (Windows 7), the CPU did fluctuate between 45-65% with every camera.
Note that to achieve 720p, Logitech recommends this: “For 720p video calling we recommend at least a 1Mbps upload and download internet connection, and a 2 Mbps connection for 1080p video calling. We recommend a 2.4 GHz Intel Core 2 Duo or higher with 2 GB of RAM. (For specific requirements please check your preferred video calling client’s homepage, as requirements can vary.)”
As you can see, this is more than what my Macbook Air (gen 1) is capable of. Yet, while testing with the 6-Core 3.8GHz desktop, we did not see a noticeable difference in image quality. According to speedtest.net. our Internet speed is 30Mbps/7.5Mbps
Tip
I wanted to point out that modern Logitech webcams work very well with the default Windows USB camera drivers. These days, most of the work is done inside the camera anyway, so I don’t need to install any software that came with the CD. These are “Extras” that may be useful, but they are not mandatory.
Conclusion
I really like the tripod attachment unique to the C920 webcam
The Logitech HD Pro Webcam C920 is a great webcam, which I warmly recommend to video-call enthusiasts. If you want to take a look in relation to pricing, here is the layout of the land: on Amazon, the C920 Costs $90, the C910 goes for $64 and the Quickcam Pro 9000 for $50. It is clear to me that for $14 more, you should get the C910 as it has better color reproduction and image quality. If you have a small laptop, or call in a Window, this is more than enough.
Video-call enthusiasts should take a good look at the Logitech HD Pro Webcam C920 as it offers noticeably better image quality, and Logitech did not crank up the “sharpening” filter on that one, so the picture looks more natural. Honestly, I haven’t looked at webcam pricing for a while, and I was surprised that the C920 was already a $90 webcam.
If you have question about something that wasn’t covered, leave a comment, and I will try to address it as soon as I can. I hope that this review gave you a good overview of the Logitech HD Pro Webcam C920.
Specifications
H.264 HW encoding for faster, smoother HD experiences
Carl Zeiss optics with premium 20-step AutoFocus
Full HD 1080p video calling on Skype
Full HD 1080p recordings and Fast upload to Facebook, Tweeter and YouTube
High quality dual mic for stereo audio
Tripod ready base
Official home page