EOS R8 Clog3 indoor videos very dark

[Damiano]

Hey everyone. I am brand new to the video recording world I have a canon R8 so I’ve been watching videos and everyone seems to suggest recording in Clog3 with an ISO of 800. I tried this indoor and the video is very dark. My question is without extra lighting. Is it possible to keep an ISO of 800 indoor and increase exposure without extra lighting? My Lens is 24-50 stm. A is at 5 and shutter at 60 or 125. Would it help with a new lens with a higher aperture? Like 1.8? 

[rs-eos]

Without knowing the lighting conditions in your indoor area, it will be difficult to say.

However, when taking a photo in my office (all light blocked from outdoors; just two 60 W overhead lights on), it was between 2 to 3 stops underexposed for these settings: f/5, 1/60 s, ISO 800. Thus, I would need to add additional light if wanting to keep all those settings as-is.

With your lens (widest aperture of f/4.5), you really have no choice but to add extra light or raise the ISO.

Also, recommend you keep the shutter at 1/60 (assuming you're capturing 30fps). i.e. use the 180º shutter angle rule. If you're shooting 60 fps, then use 1/125 shutter.

If you cannot add extra light to the scene, and are introducing too much noise with higher ISO values, your only option will be a lens with wider aperture.  e.g. in my office example, opening my lens to f/2 gave a proper exposure when at 1/60 and ISO 800.

[Damiano]

Yes forgot to mention I’m filming in 4K 24fps. Would a different lens make me achieve it? Like a 35mm 1.8? 

[rs-eos]

At 24fps, you could use a shutter of 1/50, but that would only give you a 1/3 stop increase in exposure.  Yes, an f/1.8 lens would let in around 8 times the light as your current lens (3 stops).  That would give you many more options.

However, there's always a trade-off. At the wider apertures, depth of field will become more narrow. So you'd need to balance the aperature and ISO depending upon the depth of field you need.

[Damiano]

Yes makes perfect sense. Thank you so much for your help