corona sky

[Basshunter]

Yeah, some Corona processing controls behave really strange. I've talked about some of them in other threads. Hope the devs pay attention to that in the future.

On the other hand, I don't like the "straight out the camera look" either. At least not for the final image. But I think that having the ability to mimic that would help me in many ways. In fact, I think that having the ability to make the creation and post-processing of CG still images as close as possible to photography would bring a lot of benefits. But my English is not that good to enter in such a discussion. And at the end of the day, developers have the last stand on this. To make that possible they would have to start paying attention to simple requests like fixing the post processing tools inside Corona to behave like they do in photography software or give us the ability to save images in DNG for example to be edited easily later. I'd also love to have built-in presets that mimic some camera behavior like iPhone Camera.

I know lot of people prefer to work in a more "artistic" way, without having to constraint to real world rules when it comes to CGI. That's not my case. I'd like to have less guessing in my job. So for me having the possibility to replicate the real world and getting images that are as close as possible to what I'd get straight out of an iPhone or other camera would be wonderful. Then I could take that "photo" to LR or PS and for further editing and turn it into whatever I want. Anyway, I'm probably just rambling at this point.

[Juraj]

Well, I ask the devs for DNG 4 times per year at least :- ).

The ACES OT Tonemapper (not to be confused with full ACES color pipeline, which would not improve the realism in any way anyways) is very close to film/camera look as it gets.
It's perfect starting point. But it's also full tonemapper, so you cannot bring it to Lightroom or ACR and change exposure, highlights, shadows, etc..
And most framebuffer modifiers don't work correctly positioned before the ACES OT, but that's another longer discussion.

Honestly though, 95perc. of my "look"  these days is just ACES OT + Contrast/Curves + Some personal LUT for colors. Nothing secret or special in any way.

In fact, the screenshot in this thread is just ACES + Contrast. Looks good to me.

[aldola]

Don't you think that the aces ot is very contrasted? especially in the shadows, I would have liked a better explanation of their use from the corona renderer team

[Juraj]

Well it tries to emulate filmic response, and that was always S-curve with much deeper lower part. I don't find it very contrasty I can easily add 2 or 4 points of CoronaContrast until I like the result.
Ideally it could be countered with some shadow parameter but the final result is clamped and any modifier before ACES OT gets broken because it operates in linear space and it wasn't written to work like that. (I asked the devs about that many times, I never got any answer, the whole post-production stack just doesn't work well right now as it was designed at different stages and now it gets mixed.. and...that's long discussion, I gave up. Post-production is just not strong point of Corona Team, and I am happy we have what we have).

What use explanation would you want from the team? How it works internally? (Just filmic tonemapper). How it's meant to be used? (Just another alternative tonemapper).
I can completely replicate how it works with something like (HC=2, S-Curve and Saturation LUT that desaturates highlights). The ACES OT is bit more complicated, but I can replicate the look with 99perc. Which is why my new renders look exactly as my old renders :- )

[aldola]

yeah i worked with  10 hc and a contrast lut, somehow ACES OT looks a lot more contrasty, it is possible to add HC to ACES OT in the stack?

[Juraj]

Technically you can do any combination, it's just that most of the combinations aren't meant to work :- ). But you can also combine something to your liking.
Little bit of HC before ACES OT is effectively stronger highlights correction. But we're talking HC 1.01-1.5 +/-. Otherwise you flatten the whole whites.

[leviathan420]

and any modifier before ACES OT gets broken because it operates in linear space and it wasn't written to work like that.

sorry i get a bit confused with that whole stacking order thing ,by default acesot is at the bottom of the stack,so u mean it should always be at the top of the stack ?

[Aram Avetisyan]

and any modifier before ACES OT gets broken because it operates in linear space and it wasn't written to work like that.

sorry i get a bit confused with that whole stacking order thing ,by default acesot is at the bottom of the stack,so u mean it should always be at the top of the stack ?

Hi,

The operators are applied from top to bottom. It is generally a good idea to have ACES OT at the bottom of the stack, as after applying it (and some other oeprators) the image is not linear anymore (the real render values are clamped/compressed).

You can of course experiment and see what works for you.
The thing I would not recommend - having ACES OT at the upper part of the stack.

[leviathan420]

got it,thanks for replying