Corona Sun - additional control for reflected/refracted intensity

[pokoy]

As the title says. It would be very useful to have a separate control for the sun's intensity in reflections and refractions. Either as a multiplier (factor of direct intensity) or as an absolute value.

[Ludvik Koutny]

I think this is way too much fakery already. This would break the intention of corona being physically based renderer. If you need to compensate for such things in order to make your renders look good, then you are doing something wrong in the first place. Also, it would make all parts of corona full of various knobs dedicated just to guiding users to use wrong workflow and making renders look worse.

I would first suggest you try to spend some more time with Corona, and at least try to adapt your workflow to be little more physically based. Corona will never become Brazil. For example, if your sun reflection is too strong, then your material may be too reflective in general. If you decrease reflectivity, and sun looks ok, but other reflections are gone, then maybe your environment intensity was not correct. Also, when you take photos, you usually see that sun reflections are accompanied by very strong glare, which corona does not do. So often you may just think that sun reflections are unrealistically strong, while they just miss that secondary optical effect (glare) which your eye expects to see.

[Ondra]

sorry, this is a little too much fake-y than I would like to corona to be

[pokoy]

Hmm, I guess any artist (from small shops to large studios), if asked by his client if he can dim the reflection of the sun, would be happy to say something different than "Sorry, not possible."

So, he'll disable the sun from reflections and create an object to replace the sun with a material he can fully control. There goes your physically based rendering. Why not simply allow him to save time and do this in the sun object directly? After all, you allow the sun to be invisible in reflections, give it a different color than physically possible etc. and people love it - because they wanted it.

Every single image, be it from a small shop doing stills or from a highly acclaimed studio, is carefully designed, directed and revised, and in almost all cases they will go for 'looks good' instead of 'looks physically correct'. Why should you want your software to limit their possibilities?

I realize trying to convince you is in vain. After all, it's just a time saver that some people will think of as a benefit.

[Ludvik Koutny]

I did a lot of shots recently, and lots of them had artistic direction, but no one ever complained about sun reflections. If they do, you always have option to render in passes, and dim the sun in reflection pass selectively.

There needs to be some sort of balance. If you need to do some advanced fakes, then it's easier for you to have 20 knobs to control everything, but it makes it a lot harder for new, or even experienced user, to then orient in UI full of all the spinners and buttons, and it becomes as frustrating as Vray is.

I personally know a lot of people from different studios, and while they sure sometimes need to make adjustments that break physical accuracy based on the client feedback, it's very rarely tweaking breaking relation between light intensity and it's reflection, and if that very rare occasion comes, then the workflow you have described is in place. Most people do not do these things 30 times a day.

Mental Ray not having this, Vray not having this and Arnold not having this is a nice proof that there's not too many people needing such a deep fakery.

http://www.progressivefx.tv/work/jeep-renegade/

http://www.progressivefx.tv/work/jeep-poem/

Here are two ads we done for Jeep. Half of the shots were done by me, other half by my friend and colleague Martin. All cars and environments in car scenes are fully CG, and even though there were tons of client comments, not once we had to resort for such a deep fakery as you describe.

Of course i understand you do quite different work for quite different client, but i still do not believe you need to do such drastic fakes to get good looking results. Again...  i think you should first try to adapt to physically based workflow... at least give it a shot...  because you can not expect to apply all workflows you learned using your old engines to the new one... Brazil was completely based on fakes, it was basically scanline renderer on steroids... ;)

[pokoy]

Ah well, I'll work around it then. Thanks for taking the time and explaining your point of view.

[Ondra]

Why should you want your software to limit their possibilities?

Because fakes and modern high-performance realistic rendering do not mix very well. Each fake added limits the speed of rendering and/or speed of further software development.