The picture quality is great on all 3 models and surpasses anything I have ever seen in Webcams. Razor-sharp Full HD video and faster autofocus up in the macro range. QuickTime 7 or 10 detects the cameras in the resolution "means" than than 720p with H.264, at high resolution only as 1080p with Apple ProRes 4444 (up to 330 Mb / s). The latter stressed the Mac much stronger, so that it might possibly occur in older bucking guess. Unfortunately, the new C930 QuickTime X is not recognized with H.264 encoding at 1080p, which I had hoped due to the advertising. The built-in stereo microphone is quite usable, but running without driver but only with low sampling rate. For music recordings you should allow yourself an external USB interface with good microphones. The best a simple stereo interface that is easily detected unlike some multi-channel interfaces of QuickTime.
Difference C910 - C920 - C930e: The C920 has a Full HD sensor chip (1920 x 1080) and provides approximately 30 frames per second. The older model 910 has a higher native resolution of 2592 x 1944 and is slightly slower. The higher resolution is good for photos but not much use if you videos in 16: 9 format will take up. When C920 also the mounting has been improved, it is no longer wobbles so and also has a tripod socket. The new C930e is a C920 with a stronger wide-angle, greatly extended zoom range and a little clearer picture. However, it sharpens more so the picture somewhat noisier. The 930 has a white front light, which in low light is not so conspicuous as the blue lighting of the older models.
Here are a few tips:
1. With a little app called "Webcam Settings" from the AppStore can OSX all settings such as aperture, focus, zoom, color saturation, white balance, etc. adjust completely manual (also works with 3 connected Cams). The settings are retained as long as the cams are connected. In addition, there is also a free Webcam App Logitech the AppStore, but less can be used as Webcam Settings.
2. The paid app "iGlasses" Although only 720p, but it is also recognized by Final Cut Pro X, so you can now import directly from the webcam in FCPX. This was previously possible only with the built-in iSight camera.
3. I have jokingly three Webcams (2x C920 and C910 1x) via USB 3.0 and a hub connected to the Macbook and each started a QuickTime Capture (each in its own instance). All 3 Cams be recorded simultaneously, but can only be achieved 720p, otherwise the data throughput is too large (max 480 Mb / s even with USB3 ports as the cams only USB2 support). Thus, for example, a video produced with different points of view.
4. While Logitech offers a quite hidden camera software for Mac, but that is just scrap as the Windows software. So: Hands off! The Logitech software on both operating systems do not even install !!! Both cams are detected even under Win XP and Win7. Whether there also go several cams simultaneously, I have not tested.
