iMac: Running Hot with iSight camera turned on? I have an iMac (21.5-inch, Mid 2011) with OS X El Cap. I noticed that it appeared to be running hotter than usual over the last few days. This sort of thing happens when I’m doing a lot of video work, but not on this occasion.

I don’t think it’s overheating, but I would be interested in learning why it’s hotter. 

I did have the camera turned on to monitor things while I was away, using iCam Source. I am also using iGlasses to improve the image.

Since turning iCam Source off, and hence the camera, the machine seems to be cooling down.

The question is: is it normal for the camera to heat up the Mac? Or should I look elsewhere for a cause?

Thanks
It's normal that your laptop got heated that much. It's not because of the camera, actually. Even if you'll switch to external web-cam, you'll still have this effect.

The CPU is being heated because it has to process really heavy thread of video data, to encode and to process it on the flight. 

I have this effect on my laptop as well, especially on long skype meetings or when using other video processing.