Live View exposurre simulation disable

Started by [email protected], March 18, 2014, 05:59:30 PM

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[email protected]

Can anyone please tell me if ML can be used to disable Exposure Simulation on LiveView on the lower end cameras such as 1100D?

As background, when the 1100D is set to Manual mode as it would be used in a studio Live View is automatically set to Exposure Simulation, which in effect means that you have a black screen as the studio flash creates the light, that actual exposure is black.  Camera does the same if you slip a hot shoe adapter into the hot shoe.  Basically I think Canon is trying to prevent Live View being used in a studio setup on their low end cameras.

dmilligan

nope -> http://builds.magiclantern.fm/#/features

But I don't see how turning exposim off could possibly help you, as exposim makes the image brighter, not darker. AFAIK, the whole point of exposim is that when you use a shutter longer than the LV framerate (which is impossible for the camera to do, i.e. you can't take 30 1/15s photos per second), the camera compensates not being able to make the shutter longer, by applying digital gain, so that what you see on the screen will be approximately the same brightness as when the picture is taken (which stops LV and takes a regular photo, which can be of any length).  As long as your shutter speed is not slower than the LV framerate, then exposim isn't doing anything.

You can use LV display gain though, which sounds like it's exactly what you need.

a1ex


dmilligan

I did, and it does exactly what I described. It does nothing if the shutter is shorter than 1/30 and makes the display brighter if the shutter is longer than 1/30.

If you have it turned off and go from 1/30 to say 1/10 nothing happens. If it's turned on, the LV image gets brighter.

a1ex

Try changing exposure settings, for example 1/4000. Then turn ExpSim off => the image should get brighter.

Make sure expo override is off (because I assume you were talking about Canon's ExpSim).

dmilligan

Tried exposim on -> 1/2000 -> 1/4000 ->exposim off, I don't see any difference when I turn it off.

a1ex

Try expsim on, normal exposure at 1/30, then 1/4000 (yes, underexpose), then expsim off.

dmilligan

Quote from: a1ex on March 18, 2014, 10:35:32 PM
Make sure expo override is off (because I assume you were talking about Canon's ExpSim).
That was it. I guess I didn't realize that the default behavior of LV is that it always uses the same shutter speed no matter what and then exposim adjusts it, or at least that's what seems to be going on. If I turn them both off, adjusting the shutter does nothing.

a1ex

In M mode, expo override is actually some sort of ExpSim, but it's limited by FPS.

If you enable both expo override and ExpSim, ML uses a custom ExpSim algorithm that extends well into the darkness (it bumps display gain and knows about FPS override and bulb timer setting, so you should find it useful for long exposures).

dmilligan

So I guess the real problem here is that LV is displaying the ambient scene lighting, which, when using a flash means it's going to be way darker. I guess a solution would be ML's expo override being aware of a flash being connected and automatically boosting the exposure by some configurable amount. Has anything like this ever been requested?

a1ex

Good point, it can definitely be implemented via expo override.

ExpSim off is effectively auto-exposure for LiveView, ignoring your dialed exposure settings.

pssotteczka

was this function implemented already?
I'm begginer ML user :)  could you please tell me, how set it up...? thanks   

dmilligan


pssotteczka

When can I expect it will be implemented, even  in nightly builds?