Freeze exposure after REC start & Manual ISO in Av/Tv

[HugoFilipe]

Hi,

I've search on the feature requests, on not possible and to-do list and I was unable to find this request.
What I figured out that would be really helpful on my recordings was a function that, when I use Av or Tv modes (on events with variable light with no time to manually expose), the exposure was always measured until I press the record button, from that time until the recording has stopped the exposure was kept as it was in manual mode.

Other thing that would be great was manual control of ISO on Av or Tv modes, i use a 5D3 recording raw, I want the exposure to be compensated only with speed or aperture (Av or Tv) but with constant ISO. This works great in photo but as soon as i set it in movie mode it shows a message saying that its not available in auto modes.
This is a issue when recording RAW because there is no intermediate ISO's, so an ISO change is really noticable.

This basically are 2 feature requests, but since they are related i posted on one post. If needed i can split.

Thank you very much