Topics

1

[Max] I need help! / noise threshold and tone mapping

« on: 2025-06-09, 15:07:17 »

Hello!

I wonder if the noise threshold is affected by the tone mapping? As I understand the noise measurement is based on the local contrast between pixels, right? And tone mapping and LUTs can affect the contrast, so does that in effect change when the render limit kick in? Will I get a longer and cleaner render if I increase the contrast with LUTs? Because I have a feeling that I'm getting shorter but noiseier renders when revising an old project, but rendering with my LUT off, because that gets applied in post. But it's just a feeling, I don't have any numbers and that was months ago on a different Corona version also.

2

[Max] General Discussion / OpenPBR Material

« on: 2025-04-28, 10:16:04 »

Hello!

Since of 3ds Max 2026, the standard material in Max is now OpenPBR Material. I'm not using 2026 in production yet, but this has sparked my curiosity and I would like to know if there is official documentation on what is supported and not in Corona?

After some breif testing it seems some parts work while there are some stuff that doesn't work as expected, much like the old Physical material. It's nice that it renders anyway. But are there plans to fully support it?

This would be really good since this looks like a material a lot of applications will support. And this would allow for building of assets and working in Corona, while still having to option to move things to other DCCs.

Also fully supporting it would mean implementing thinfilm, which doesn't make much difference to me right now, but I know it's been requested before.

3

[Max] I need help! / Batch convert CXR

« on: 2025-03-28, 08:39:04 »

Would it be possible to take an entire folder of CXR files and save them all (and all render elements) as 16-bit TIFF?

I know of CoronaImageCmd.exe and the possibility to create a batch job, but I don't know how to set the specific settings of the output format. Accoring to the documentation CoronaImageCmd.exe --help "will print general help". But for me it doesn't print anything.

There was a user made GUI for the batch editor that I found when searching, but the download link doesn't work for me. Isn't it about time that an official proper batch tool with a GUI is made? Or just extend the functionality of the CIE?

4

[Max] I need help! / Corona Light Texmap viewport visibility

« on: 2024-11-19, 09:05:33 »

Hi!

I just want to get it confirmed that I'm not missing something and that Corona Light doesn't display the applied Texmap on the Corona Light (rectangle) in the viewport?

If it could, it would be useful for product visualisation when applying gradients and such to rectangluar lights. To seem the mapping of it in the viewport directly before rendering.


It would also be very cool if we VraySoftbox was ChaosSoftbox and available in both renderers! It's a super simple map, I can't imagine it would take an actual programmer many hours to make something like that. I'm even thinking of going through the hoops of having a chatbot create a softbox map for me in OSL.

5

[Max] Feature Requests / MultiMap Gamma variation controll

« on: 2024-07-02, 10:02:34 »

Hi!

Often I find myself adding random variation to instances, mesh elements or Tile IDs using MultiMap with a single input and random gamma. But it often makes some elements too bright, and I have to "pre-darken" the color. If I could control a bias of the gamma or even have a -/+ controll like on the UVWrandomiser it would be really great! So I could make it go -5% and only +1%. Acctaully having - and + for hue, sat and gamma would be great. I don't know if it's usefull for hue, but for sat and gamma it definitely would.

Anyone else been thinking the same thing?

6

[Max] I need help! / Lens tilt/swing?

« on: 2023-12-15, 16:01:33 »

Hi!

I suspect this is way too niche and also something that will fly over most heads.
But I wonder if someone with insight into writing a ray/pathtracer (preferably a developer of corona ;) ) could answer if it would be possible to implement lens tilt/swing in order to change the angle of the focus plane according to the scheimpflug principle?

Doing product shots in Corona, I use a lot of lens shift to obtain desired perspectives/projections - as one would do in a real studio. And it would be cool if I could have all the tools of a physical camera in corona too.

Using tilt/swing in real life is really really hard. But having focus plane preview on the corona cam, it would be a nice tool to have up my sleave.


</ weird question that probably doesn't deserve much attention in the grand scheme of developing corona render>

7

[Max] I need help! / Corona Image Editor writes (possibly) corrupt TIFF

« on: 2023-11-16, 08:50:38 »

Hello,

Is there any known limitation to resolution or file size when it comes to tiff?

I've rendered to CXR, and I save as TIFF from Corona image editor, and suddenly nothing will open the files. Saving as PNG works. The only thing I have changed in the setup, apart from geometry and materials is that I bumped the resolution from 11600x7733px to 12000x8000px. Either the output is corrupt or Photoshop can't read it. But photoshop can create, save and read a Tiff of that size so I don't think that's the problem.

8

[Max] I need help! / filtering, bump and roughness

« on: 2023-10-09, 14:49:30 »

Hi!

I remember seeing threads about how Corona takes shortcuts with filtering so we can how our nice and quick renderings, and that this usually isn't a problem in most images/scanarios. I just lost my perfectly tweaked highlights in my powder coating when going from testrenders to rendering 11,6K. Test rendering at that size isn't realistic, hardly even with regions.

What should I do to make sure my highlights have the same roughness/bump no matter what render size? And how bad will the penalty be?

9

[Max] Feature Requests / View LUT?

« on: 2023-09-19, 14:02:29 »

I've seen on trello that VFB and color management is being worked on. So maybe this is in the works already.

I've would like to have a LUT in the VFB that doesn't get applied to the output, a "view LUT" if you will. More savvy people in the area of color management and color grading will probably have a better word for this an also want to use very specific view transform LUTs. I just want to preview my render with some extra punch, but then not have it burned in and then finesse it manually in Photoshop :)

10

[Max] I need help! / Camera and White Balance questions

« on: 2023-09-11, 12:04:26 »

Hi!

Am I getting this right? Corona ignores WB setting of PhysCamera? IR starts over as if there was a change, but nothing changes. If it's not supported could we please have an option in Tone Mapping like Photographic Exposure, to also use WB settings from the Camera? I have cameras in different places :)

BTW, I noticed Corona Camera doesn't have focus breathing? (or I can't find it)
It also doesn't let you enter or see exposure in EVs which is a con for me. I don't think I'll ever convince anyone here how useful it is. But trust me, I've worked as a photographer professionally on the side of 3d for over 15 years - it's not that I don't know how to set a camera in manual mode. Mine is parked in manual mode.

11

[Max] I need help! / Performance penalty when using Max native Physical Material?

« on: 2023-03-01, 09:53:22 »

Hi!

Corona seems to fully support the Physical Material that is native to Max. Haven't checked all the features yet. But, is there any penalty in performance when using it?

Of course I prefer the Corona Material when ever I can, if just for easy of use. But there are situation where using only Max native material and maps might be necessary. Does anyone know if I would be looking at a severe performance hit? Or are we talking about a 1% increase or something like that?

12

[Max] I need help! / Render to texture, bake to texture

« on: 2023-01-06, 16:08:20 »

I feel very stupid now, but I thought this was something that one could simply just do. I'm having a lot of trouble and I can find very little info. And I just saw this:
https://support.chaos.com/hc/en-us/articles/4528523245073-How-to-use-texture-baking-in-Corona-for-3ds-Max-
"Note: using the projection modifier is not yet supported. "

So how does the projection even work!? I get black areas where high/low intersect and I just got around this but temporarily using a push modifer to grow my low outside the high one.

And I need to get out metallic, roughness and emission too. (Haven't tried the light pass yet)

Seems like I need to convert my entire project to arnold or generic Max materials/maps and bake with arnold or something instead. I know this kind of work isn't Corona main area of expertise so maybe I am kind of stupid for not checking this in advance. Spent many days setting up photoreal renders of a product hoping to just quickly bake it :( But this feature seems only half-baked in corona ;)

13

[Max] I need help! / Camera and exposure in Corona 8 + TintOperator

« on: 2022-04-14, 11:56:59 »

It was very confusing to not be able to use photographic settings right away. Eventually found that I had to add it to the tonemapping stack. But it's kind of wierd that I can still enable simple exposure, but the spinner is greyed out and I cannot change it.

Very glad to see the term EV removed from simple exposure! This was very confusing for people when it didn't mean the same thing as it does in the rest of the photographic world.

Would it be possible to get real EVs as an option on the photo graphic exposure and/or basic photographic settings? I know Juraj told me it was an antiquated/obsolete term or something. But I think it's really wonderful way of simplyfying exposure and it's been around for ages. There's lots of reference. And it's a really excellent tool when I teach visualisation students to get them in the ball park of how much light is reasonable for a scene. Juggling shutter, aperture and ISO is too much for them. So we look at loads real world examples and what EV they were shot at. So they know a bright daylight scene is around 14 EV and an bright office interior is 7-8, and that's also good for blue hour exteriors.

And what does this really mean?

"Physical camera: The following operators are supposed to be overridden but they are not in the tone mapping pipeline: Chaos.TintOperator.Data"

I just made a phys cam and tried to render with daylight system. I don't get the error messange when I open an old scene made in Corona 7

14

[Max] Feature Requests / Nesting multi/sub in layered material

« on: 2022-03-07, 22:08:31 »

Such a boring request :) I really thought it was possible and was quite baffeled when it resulted in a warning. The other renderer can do it I believe. And it would be super practical to be able to put dirt and other stuff on top of a more complex materials. I have a terrain or some streets with sidewalks and parks, that all are defined by one big multi/sub material. Would be nice to be able to put a dirtmap on top of all of it, instead of nesting a unique material manually between each sub-material and the multi material. Can't you like programatically tell the renderer to do basically that when there's a layered on on top? Is this difficult or is there a risk of a slowdown or loops?

15

[Max] I need help! / instances, instancing and proxy

« on: 2020-01-14, 16:48:37 »

Hello!

I did some searching of course, but just got more confused about memory management with proxies.

So I'm going to ask some very simple and stupid questions here to clear this out for myself once and for all.


In Corona on 3dsMax I have a thousand identical teapots, do I save any memory what so ever at render time if:

A. all teapots are regular max instances? (as opposed to copies)

B. all teapots are proxy? (all as instances, linking the same .cgeo-file)

C. all teapots generated with forest pack?