Here are some tips over video solutions for your recording, streaming or on-line lesson.

Webcams

Webcams are easy to use. You plug it via USB to your computer and it is ready to go. A webcam can be used for video call, streaming and even recording. Most of the laptops already come with a built-in webcam, but you can always use a higher quality webcam for a better image. In case you use a desktop computer, then a webcam is an easy solution to have a camera input on your computer.

Here are some suggestions:

Logitech C270 HD

Razer Kiyo

Logitech StreamCam

Logitech C930E HD Pro Webcam

Zoom Q2n

Zoom Q2n is a tiny versatile device which records decent video and audio as a standalone device. However, if you connect it via USB to your computer, then you can use it as an external (USB) microphone as well as a webcam. That way, it can work as an all-in-one solution for video and audio. There is also the 4K version with higher video resolution as well as Q4n and Q8 with more feutures.

Using external camera (with capture card)

It is possible to connect an external camera to your computer in order to achieve much better image quality. The benefits are: higher dynamic range, better contrast and higher resolution. Also, the camera lens gives you more flexibility in terms of field of view (in case your camera has a zoom lens). In comparison to build in computer webcams, external cameras have better performance in low light situations as well. Basically, any camera such as DSLR or camcorder which has HDMI port would work. 

To connect a camera to your computer you need a video-interface in between, also known as capture card. Here are two examples: 
CAMLINK 4K is an affordable plug&play dongle & 
Blackmagic Webpresenter is a more professional option with more features such as microphone input. At the Conservatoire we use this device for streaming sessions. Here are some more options:

AJA U-TAP-HDMI

Magewell USB Capture HDMI Gen 2

Magewell USB Capture HDMI 4K Plus

The following links give you more information about such setups as well as some more suggestions for a video capture card. Keep in mind that you would also need the right HDMI cable to connect your camera to the capture card. 

Using a camera without capture card

In some cases it is possible to connect the camera directly to the computer via USB cable without any capture card. The following links demonstrate that method for Canon and Sony cameras.

Blackmagic Atem mini

If you want to go even one step further and use multiple cameras to show different angels, Blackmagic Atem mini is a great device which works as a video (HDMI) switcher as well as a capture card. Basically, all you need for a higher level streaming, video call or even recording.