Disable automatic expo correction when zooming with variable aperture lenses

[JABA2]

Canon cameras have an interesting bug. Whenever you zoom in and out with variable aperture lenses in movie mode, the exposure changes a little bit, even when you set everything to manual and set the aperture to its smallest value.
Example:
When using 18-55/3.5-5.6 lens on my 600d, I set everything to manual and set aperture to 5.6. But whenever I zoom in and out in movie mode, there's some auto adjustment going on that makes the image a little brighter/darker.
Curiously, if you unscrew the lens from the mount a bit, so that it loses electronic connection with the body, this problem goes away, so this certainly has sth to do with Canon firmware.
It would have been great, if this could be fixed via Magic Lantern, for example by fooling the camera into thinking that you are using a manual chipped lens, whenever you enter Movie Mode.
Hope this gets implemented, 'cause it'd finally make the variable aperture lenses usable for video.

[dmilligan]

It's actually trying to hold exposure constant. Problem is that zoom is continuous but aperture blades move to discrete positions. If you go from 18 to 55 with your lens and keep the absolute aperture the same physical size (don't move the blades, like when you unscrew it) the effective f number changes (because it's the ratio of focal length to focal diameter, and you're changing the focal length). Therefore your image actually gets darker.

Turn on the spot meter, unscrew the lens, and zoom, and you'll see what I mean.

[JABA2]

Nevertheless, it's better to have your image get a little darker than flickering like crazy.
And since this feature has not yet been implemented, would you please move it back to feature requests section?
I assume this is what it is for - requests of new features.
For now, the only workaround I have for this issue is to unscrew the lens every time which is quite annoying.

[a1ex]

The request is valid, though it was asked a couple of times (that's why it ended up here).

http://www.magiclantern.fm/forum/index.php?topic=2964
http://www.magiclantern.fm/forum/index.php?topic=9776
http://www.magiclantern.fm/forum/index.php?topic=11162
http://www.magiclantern.fm/forum/index.php?topic=15495

I have an idea. Does the aperture get corrected when recording raw video? There, we disable the auto exposure from Canon code in order to squeeze a little speed for recording. If that works, the workaround would be pretty easy to implement.

[JABA2]

I have an idea. Does the aperture get corrected when recording raw video? There, we disable the auto exposure from Canon code in order to squeeze a little speed for recording. If that works, the workaround would be pretty easy to implement.

Just checked and it works in raw! The aperture does NOT get corrected.
And if it's easy enough to implement, it would've have been awesome if this feature got released for 600D!