Are you curious what ISO levels work well for YouTube videos? So am I, let’s figure out it out together!
First a quick background on ISO levels and why they matter. ISO is the sensitivity to light of a digital camera. When trying to setup a scene, you want to get the right exposure. If i had an image with a lot of light, and it was overexposed, the white in the image will look blown out. For example, let me overexpose what you’re looking at right now and show you what that looks like.
So the goal is to expose the image at a level where the whites aren’t blown out but theres enough light in the scene to see your subject matter. If it’s too dark or the contrast is too high the blacks will blend together and you won’t have a clean video. When setting up a shot like the one you’re looking at now, there’s a 3 settings that you want to focus on to expose an image, Shutter Speed, Aperture, and ISO. There’s a famous exposure triangle image you can google that explains this more in depth, or I could do a video on this in the future. Right now I’m in optimal lighting conditions and am filming at f/2.0 aperture, 1/30 shutter speed with ISO 100. ISO 100 is the lowest my camera will go, and therefore the BEST setting. But you won’t always be in perfectly lit conditions, and when filming in low-light, you will most likely have to increase the ISO to get usable video. The cost to increasing the ISO is a noisier image. At some point the image will be too noisy to be usable.
So let’s do some testing. The camera I am going to use is the Canon m50, which is an entry level camera with an APS-C crop sensor. Just know that a full frame camera would let in more light in a comparable test. For this setup I am filming at 30 frames a second full HD 1080p, and going to use a shutter speed of 1/30. I am going to use a fixed aperture of f/3.5. The only thing we are going to tweak is the ISO. I will however be shooting with 2 different lenses. I will be shooting with my Canon EF-M 22m f/2 lens and my Canon EF-S 18-55mm with the Commlite adapter for EF-S to EF-M.
The EF-M lens is a native lens to the Canon M50 which can let in more light, but again ill be using f/3.5 at 22mm.
The EF-S lens is an old kit lens I got with my T3i which can only go as low as f/3.5, and it will be focused at 22m. I’m testing both to see if the quality is different between the two lenses, since one is native and the other is not and connected via an adapter. I will be cranking up the ISO in equal increments and seeing how it performs in low light and how noisy it gets.
Now I’ll give my analysis on what we just saw. Again if possible shoot at 100 ISO, that’s your best setting for video, but when not possible i thought approximately 800 was acceptable. it was a nice blend of good exposure on the image, and there wasn’t too much noise in the image. This is of course viewing the video at full screen FULL HD 1080p. Now here is where maybe you can fudge things a bit. If your audience is primarily a mobile audience, try looking at the video tests on your phone, and let me know if you change what you think the highest acceptable ISO is. After viewing it on my phone, I feel like I could let the ISO go as high as 1600 and it still looks fine. So keep in mind, if you have a target audience you can tailor this to, and are happy with the results, feel free to fudge that a little.