VERY handy when it comes to complex fly through animations, when camera travels through areas of different lighting
Insight render had it
super simple
pre-render a frame at a set low res and arrive at a average exposure number, before rendering production size and quality
give users a multiplier to manipulate the resulting desired EV up or down
to prevent flickering in the animation pre-render (-2, current, +2 frames) and average the EV value out
there may be a smarter way of doing it, but that’s how it was handled in Insight, and worked like a charm
thank you!
PS there’s always a chance that i’m missing something, and there’s already a way to accomplish autoexposure, in which case please point me in the right direction
Sorry, it does not seem to be that useful, compared to the relative complexity it would take (prerendering animation at low res), so we will not implement it
may be there is a smarter way to do it? i just gave you a brute force approach
right now there is no easy way to control exposure if the camera travels through areas of drastically different lighting conditions, say between lit and unlit spaces or exterior to interior
manual animation of exposure will never look right and is a paint to set up
There might be a way to adjust exposure dynamically for animation, the same way Timelapse triggers (who don’t know the future) adjust exposure dynamically.
It’s called automatic BULB RAMP, in real life photography we change the exposure time over time, and the only way to do that easily is to set the camera into BULB mode and let the trigger control the exposure time by how long in presses the shutter, anyway, that’s why it’s called BULB RAMP. Of course corona could much easily change the exposure.
well, the real cameras have an advantage of metering before taking a shot
obviously for a rendering engine to “meter” it would have to generate a preview of a sort, even if strictly internally
that’s why, i think, Ondra is dismissing it as complicated
but, the size of that preview can be very small and there is no need for AA
considering the sheer speed of corona even on heavy scenes it’s a shame not to take advantage of it
even max itself has an option of auto-exposure, albeit not supported by Corona, let alone any real photo and video camera
it seems odd that developers are inclined to bring in all the complicated settings of real wold cameras letting out the convince features
ever tried shooting a non-stationary video with locked exposure? probably not, because it’ll be garbage
I’ll be the first to admit that I’m not an expert on how Corona works, but if I’m able to change the exposure while it’s rendering, shouldn’t Corona be able to do the same ?
Also, if you are rendering a video, you don’t want abrupt changes in exposure, so even if you transition from a dark place to a very bright one ( getting out of a tunnel ) It would be acceptable for Corona to take some time to get used to it. I don’t think a 1 frame delay is a big deal, but as I said, Maybe exposure can be set just before saving.
Auto White Balance and Auto Exposure are completely 2 different things. The first one is easier to do, Photoshop does it, Lightroom as well and even better. The second one is more difficult and I understand the complexity.
Personally I prefer the White Balance to be done manually in post production, much more professional move and more control.
one of the joys of Corona is that you can just tweak the exposure once you have started rendering, so no need to try to guess the EV level like in Vray. For animations perhaps, but normally I’d just quickly check it using interactive and then keyframe the camera exposure.
I can totally see how hundreds of hours of rendering goes in to a bin, if something goes wrong with either AE or AWB or both of them :] Both features could be nice for still images, but i’m not sure if i would dare to use them on animations.
I saw a video showing V-Ray’s auto exposure, and I think it makes sense in many cases (especially in animations where the camera moves between interior and exterior). I am sure we can expect it in Corona soon as well.
is it hidden? I’ve always thought it was in plain sight. although “automatic” here doesn’t describe it! automatic for vray means a different thing. the renderer sets the white balance with no user input besides clicking a checkbox.
