Using a DSLR as a webcam

Matthew Burgess May 08, 2020

When the world changed due to the global pandemic and we were made to stay home, online meetings suddenly became the new normal and webcams an important asset. Work meetings on Teams, webinars on Zoom, catchups with friends on Skype or FaceTime. This had me thinking about what would make a suitable setup for me at home.

Low quality, built-in webcam on my work laptop.
Sure, both my work and personal laptops have built-in webcams - but their image quality is quite poor and the only position for a laptop on my desk sees it facing a window and making me look like a backlit, anonymous interviewee on TV. I  used a DSLR to livestream an event a few years ago and this had me thinking on whether I could use my old Canon 5D MK II as a webcam. And whether I could do it with all the technology I had already, without purchasing anything new.

Using a DSLR as a webcam has a few advantages including higher quality video and the ability to control focus and exposure. But it also comes with a few caveats, the biggest being the requirement of a power adapter so you don't have to rely on batteries to power the camera for long periods of time

I have been using my current setup for a few weeks, but Canon recently released EOS Webcam Utility Beta to use their cameras as a webcam via USB. This would be a much easier setup, but unfortunately it does not work for older camera models. Thanks, Canon.

There are two different setups that I experimented with for utilising my 5D MK II as a webcam - the first operating on a very old computer running macOS and the latter, which I am currently using, on my Windows 10 desktop computer.

Setup One - macOS

If you have a computer running macOS then you can do this with free programs, your camera and connecting it to your computer using its appropriate USB cable. This is a somewhat similar setup to using EOS Webcam Utility, but using the following programs:
  1. v002 Camera Live for Mac - https://github.com/v002/v002-Camera-Live
    This program provides a Syphon server for a connected camera, allowing it to be used as a live video feed. Currently the only supported cameras are Canon DSLRs, see CAMERAS.md for a list.

  2. CamTwist - http://camtwiststudio.com
    This program allows other programs (Zoom, Teams, Skype etc) to see the camera feed, and for added bonus also has the ability to add special effects - I had fun with those when using this setup
You can read detailed instructions on how to use these here. I ended up abandoning this setup because the computer was quite old and outdated and could not handle delivering presentations at the same time as video.

Setup Two - Windows 10

Better quality webcam from my 5D MK II
Unfortunately I was unable to find any open source equivalent to Camera Live that works on Windows. digiCamControl looked promising, but unfortunately the streaming feature doesn't work (or at least I couldn't get it to work with other programs as a webcam). There is a commercial program that is basically a combination of both Camera Live and CamTwist on Windows, but it is almost the cost of a decent webcam which defeats the purpose. Alternatively, this is where you need additional hardware in the form of a HDMI capture device and a camera with the ability to output a HDMI signal and where you would consider buying a decent webcam if you didn't already have this hardware or couldn't justify its purchase.

While the 5D MK II has HDMI output, unfortunately it is not 'clean' in that it has information overlays - the same as what you would see on the back of the camera when using live view. To get around this I installed MagicLantern - a free software add-on that runs from the SD/CF card and adds a host of new features to Canon EOS cameras that weren't included from the factory by Canon. Using this software voids the warranty and can break the camera if used incorrectly and I was only willing to use this as the camera has a problem with the sensor and is no longer usable for photographs.

My current setup is as follows:
  1. MagicLantern running on my Canon 5D MK II with Clear overlays set to Always and Sticky HalfShutter turned on to prevent live view from turning off after 30 minutes (noting that you need to halfpress the shutter button to activate and deactive Sticky HalfShutter)

  2. AVerMedia Live Gamer Portable C875
    This is a HDMI capture device that comes with the software needed to deliver the video feed to other programs, including those that look for webcams. Any HDMI capture device should do. I used this to live stream an Australasia Preserves event back in 2018 with a different DSLR.

  3. Rode smartLav+ lapel microphone
    Unfortunately my desktop computer doesn't have the right connection to use the microphone in my headphones, but thankfully I had this lapel microphone that I had previously used to record my voice for a training session

  4. Headphones - I usually wear noise cancelling headphones because it is a much better audio experience than loud speakers (for me and those around me at home)

It is not perfect

Using a DLSR as a webcam means I can use my desktop computer for meetings, but it is not perfect. I am using a 50mm lens and it has a relatively narrow depth of field so I need to be conscious of where the focal point is. The aspect ratio is not full width as you can see in the screenshot above. I have the camera set to manual exposure so it needs to be adjusted when there are changes in lighting, not automatically as it would on a regular webcam. But overall it is a better alternative to using the webcam on my laptop and I could make use of equipment I already had at hand.