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Using a Canon EOS camera as a webcam in Debian

schlachter.xyz

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Re: Using a Canon EOS camera as a webcam in Debian

#41

Nice post, but that's way too much work to be worth it. You really want your camera and mic setup to just work rather than having to tell someone to wait 10 minutes to call because you need to reload your kernel module.

It takes 10 minutes to reload a kernel module??? Not even on a 386 :D

Re: Using a Canon EOS camera as a webcam in Debian

#42
post #36
post #35

Earlier quoted context omitted.

It is fine. I have been using an "old" canon EOS 1000 for a few years now. But I use an HDMI capture card with magic lantern running on the camera to get a clean HDMI feed.

Why do you need magic lantern for that? HDMI capture card would presumably work with stock firmware? I’ve also tried using my old 600d but with the canon provided software and it works pretty okay.

Magic lantern to remove shutter speed and other menu overlays from the hdmi feed, might also enable long duration HDMI output without the camera going to sleep.

Re: Using a Canon EOS camera as a webcam in Debian

#43
What's really interesting is Entangle.

https://entangle-photo.org/

It works with a lot of DSLRs, it doesn't require you to do any of these steps, and it captures the output. The only thing it doesn't do is then map that to an output for other applications to pick up.

There is an open request for this, but it seems to be out of scope for the application.

https://gitlab.com/entangle/entangle/-/issues/68

It could be really neat if this solves the EOS webcam issue in a tidy way.

Re: Using a Canon EOS camera as a webcam in Debian

#44

My experience of this general approach with a Sony α6100: high and inconsistent latency (mostly 150–200ms, but sometimes towards 400ms), low resolution (1024×576), largely not hot-swappable (most apps required that the video device be created before their process began, and trying to read from it without also starting the stream would often poison things in some way, and various actions would make the pieces just sto…

I also tried a similar setup (with gphoto2 getting the stream of jpegs, ffmpeg, loopback device) but the deal breakers for me we're:

- high latency: in the half-second range, consistently out of sync with the audio - bulkiness: I had to place the camera on the side of the screen rather than on top, so I consistently looked away from the camera

With that experience I didn't find it worth to upgrade the setup (with mini HDMI cable, capture card, power supply) and ended up buying a crappy webcam instead

Re: Using a Canon EOS camera as a webcam in Debian

#45
post #34

How does using a DSLR affect camera lifetime? The sensor is presumably consistently exposed?

I've used a bunch of DSLRs w/ live preview active for extended periods w/o any issues. It's solid state, so the affect should be negligible assuming you're not directly exposing it to a lot of direct UV light or something like that. For me (used to run a photo automation company), the main wear factor on Canon DSLRs are mirror and shutter actuations (after about 50K-100K actuations, the mirror will tend to detach - this is repairable via CPS), however in preview mode, you aren't going to have any of that mechanical stress.

Re: Using a Canon EOS camera as a webcam in Debian

#46
post #45
post #34

How does using a DSLR affect camera lifetime? The sensor is presumably consistently exposed?

I've used a bunch of DSLRs w/ live preview active for extended periods w/o any issues. It's solid state, so the affect should be negligible assuming you're not directly exposing it to a lot of direct UV light or something like that. For me (used to run a photo automation company), the main wear factor on Canon DSLRs are mirror and shutter actuations (after about 50K-100K actuations, the mirror will tend to detach - t…

Sensors getting hot - specially in older cameras - is a well-known problem. Lp doesnt stress the sensor enough (low fps, partially off), but filming video will.

Re: Using a Canon EOS camera as a webcam in Debian

#47
post #41

Nice post, but that's way too much work to be worth it. You really want your camera and mic setup to just work rather than having to tell someone to wait 10 minutes to call because you need to reload your kernel module.

It takes 10 minutes to reload a kernel module??? Not even on a 386 :D

First you have to spend a few minutes searching your bash backlog for the exact modprobe command, then you realize you updated your kernel so you have to recompile and resign it, then you have to fiddle with your video inputs but the gui is somehow out of sync with the actual setting. Then run a test before joining the call. And then the other person has the window under their browser and never looks at your video.

Re: Using a Canon EOS camera as a webcam in Debian

#48
post #20

I've been wondering for a while and can't find an answer to this: SD to USB adapters exist, but is it possible to hook up an SD-to-USB cable and have a driver present a virtual sd disk to the camera but write the video directly to your computer RAM via USB? That would solve the problem for all dSLRs.

SD interface is a bit complicated to set up for average hackers, on top of buffering issues. Likewise there are some cameras with PCIe derived interfaces for memory cards, but those aren’t actively being hacked either.

Re: Using a Canon EOS camera as a webcam in Debian

#49
post #30
post #28

Earlier quoted context omitted.

That seems pretty roundabout, when you have solutions like the Elgato CamLink that just takes an HDMI input from your camera and shows up as a completely standard USB Video Class device to the OS.

Many models don't give you "clean" HDMI output. It's usually low-res with overlay junk. edit: if the elgato can do it with HDMI, the question remains can it be done directly with SD out? e2: also, SD card readers/adapters are cheap and plentiful, this seems like it should be easier to implement

My DSLR camera has a mini HDMI out that you can use out of the box, doesn't require the camera to be in recording mode or such. It simply gives you the live video feed -- rather than having it write to SD card, having software on your computer decode the video & show the last frame there.

The only option I think (it's been a while) I had to vaguely enable is to have it not show the normal camera UI over HDMI, but that was a simple setting.

Having hardware emulate a SD card sounds like a niche product, if anything, whereas the only item I needed for my camera was a mini-HDMI to HDMI cable.

Re: Using a Canon EOS camera as a webcam in Debian

#50

Nice post, but that's way too much work to be worth it. You really want your camera and mic setup to just work rather than having to tell someone to wait 10 minutes to call because you need to reload your kernel module.

What work? That seems very comparable to any moderately nice webcam: Install software once, then forget about it. The "setup" for something like skype is then just selecting the cam from a drop down menu.

An argument I could see is having to get out the camera, put it onto a tripod, connecting power, ... etc.. Though that is only an issue if you cannot just leave everything set up.

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