I have a question regarding the LightMix multiplier limits. In older versions of Corona (I believe prior to v10), we used to be able to input very high values in the LightMix panel, sometimes reaching into the thousands. However, in recent versions, this value seems to be capped.
I’m curious about the reasoning behind this change. The ability to use large numbers was extremely helpful for quickly tweaking the scene lighting on the fly, without having to go back and manually multiply the base intensity of each individual light source.
Are there any plans to bring back this unrestricted input in future updates?
I think there were multiple reasons. One of them being that you are generally not supposed to use LightMix for such extreme intensity adjustments as it will always cause noise or other issues. Actually, the limit of 100 is set pretty high.
Another reason would be that with extreme intensities you could get NaN errors or other bugs.
I don’t think we have plans to make those values unrestricted again, unless it turns out to be very important for our users.
As I said, high values were really helpful for my work, particularly for HDRI images used in environment lighting. They usually come with weak intensities and can require multiplying by 200 to 300 times to start showing an acceptable result. Even some fixtures with small bulbs, like chandeliers or wall lights, require values that can exceed 1000.
I wasn’t seeing any noise, though I might be mistaken. Since I appear to be the only one who brought this topic up, I’ll adapt by modifying the light parameters themselves. I was just wondering. Anyway, thanks for the explanation!
Either increase your camera exposure, or increase light intensities directly in their properties if they are originally set too low.
The reason is that Corona maps how to render the scene efficiently based on original light intensities. The way light sampling works for a light with intensity 1 is very different than for intensity 200. If a light has originally its intensity set to 1 and you boost it 200 times through LightMix, Corona’s mapping is not correct anymore and you end up with heavy noise that might never go away or artifacts.
