CORONA LIGHT PROBLEM

[Romas Noreika]

I don't know what you discovered here maru, but I was just saying that your technique with:

corona light material - emit light off on a bulb. (I would leave emit light ON, because I want that my spot light interior would be lit, not dark)
corona light with IES profile below the spot light everything off

DID NOT WORK, I was not getting enough speculars in the scene on my materials.

Anyways - maybe one day there will be a solution for this situation with an IES light spot light setup.

Best,

Romas

[maru]

Ok Romas, in my last post I admitted that I understand the problem.

[Romas Noreika]

Also another big problem, especially in production region rendering.

Lets just say the client want to change just the sofa material or something small in the scene.

I ussually re-render just a region, why should I bother re-rendering the whole image.

So I rendered a full IMAGE in 80 passes. Then i drag a region in corona buffer and that region cleans it self up in 20 passes it is supper clean. So the question now is how the hell I should know how many passes I need to put to this region. I mean if the whole image rendered in 80 passes. That region that I draw, should render at the same quality vise in 80 passes, but those passes should be a lot faster. At the moment I have no idea how many passes I need and the region is completely different noise wise.

I did not try this with MAIN MAX region, reci it will be the same. But corona buffer region and selected element render will not be the same quality as your final image. The pass count and quality will be different.

MARU - can you please tell me how I can get exactly the same quality region as my final image rendered in 80 passes?

[maru]

MARU - can you please tell me how I can get exactly the same quality region as my final image rendered in 80 passes?

I don't think this is possible with adaptivity enabled. You can disable adaptivity, and then you will get exactly the same quality after the same number of passes, but obviously without adaptivity, the rendering will be slower. You can disable adaptivity in devel/experimental settings: https://coronarenderer.freshdesk.com/support/solutions/articles/12000021288
Once again, disabling it is NOT recommended!

[Romas Noreika]

Alright then another way of thinking.

Theoreticly if using noise threshold instead of passes threshold.

Lets just say I set my final full image to 1 of noise threshold cap.

So if I will render that region it will stop rendering at that 1 noise threshold, correct me if I am wrong? And I shouls get exactly the same quality noise vise region and full image? Yes?

[maru]

No, it does not work like that. You will get different results. For example if you have the whole image and there is a lot of contrast in it - e.g. a glowing sphere, dark background, and some flat surface like a wall, then the same noise limit will be completely different when rendering the whole image, and when rendering a part of it (e.g. a part where the glowing sphere is visible, a part where the flat surface is visible, etc.).
I can see an issue here, but currently can't think of any reliable solution other than disabling adaptivity.

[Romas Noreika]

I do not want to put Vray here again just going to say how I work with the clients sometimes,

If I need to re-render just a region I send it to a farm ant forget it. When I will open it I will know 100% that it will slap in photoshop 100% correctly no noise difference or anything else.

With corona I have to render it by looking at it and pres stop whenever I am happy or I dont know :) I am talking here about a heavy production, not some simple freelance work. :)

[maru]

I have submitted both issues (reflections of lights with "emit light" option off and different quality of region renders) to our internal bug tracker. I will be sure to report any updates here. You are also welcome to track the reports yourself:
regions - https://corona-renderer.com/bugs/view.php?id=2417
reflections - https://corona-renderer.com/bugs/view.php?id=2416