Messages

31

[Max] I need help! / Re: Long rendering time

« on: 2025-02-28, 22:57:11 »

So I did some tests, given what you said, but the problem remained, except when I turned off caustics.
I turned On Caustics so that the glass on the table casts nice light patterns on the table. And this is what is causing this massive slow down: when I turn caustics Off, the image renders 6.5x faster!

I hardly understand why, as the only object in the scene set to receive caustics is the table. How can a small object like this glass being responsible for the render time being 6x slower?!

Now you get what the text in parentheses next to caustics mean ;)

Enabling caustics without caustics solver may only improve the look of the glass (shadows/colors nearby) but the photon calculation (light shapes, ray concentration) won't happen.
Enabling caustics solver automatically enables reflective caustics, but you can still control the refractive caustics per material.

Remember there is caustics include/exclude list too.

32

[Max] I need help! / Re: How to brighten shadows in a white scenery?

« on: 2025-02-27, 13:04:39 »

Sorry, my bad, apparently visibility does not affect alpha (I may report this), but here is a good way to change the shadow density (alpha), using a trick - a light which illuminates only the shadow catcher.
Scene attached.

33

[Max] I need help! / Re: Long rendering time

« on: 2025-02-27, 12:48:27 »

First, make sure the exterior windows have simple (thin) glass - this is a common user error that can significantly increase render times.

I don't think it's the best advice to say people should model things in such a fake way. Double glazing is also a thing, and makes a very visible difference when rendered correctly. Not to mention it's not practical advice depending on whether you might receive a certain level of detail in a model from a client, for example. There will be other more obvious ways to optimise the scene before doing something like that, it's just not necessary or desirable IMO.

It has nothing to do with double glazing ;) it is about glass having no refraction (thin mode) for outside light to be calculated easier. Of course it is good to keep things as they should be, but when render times are a concern, checking this is one of the first things. I, in fact, have been using double glazed windows everywhere for a very long time. As mentioned, full scene check is the best way.
Hope it's clear now.

34

[Max] I need help! / Re: How to brighten shadows in a white scenery?

« on: 2025-02-27, 11:39:06 »

Keep the shadowCatcher as it was - for compositing. Change only the visibility parameter (or opacity) of the object. Making an object invisible to camera will of course remove it from view.

35

[Max] I need help! / Re: How to brighten shadows in a white scenery?

« on: 2025-02-26, 14:12:14 »

Is there something I can do to minimize the shadow noise directly in Corona (without having to wait for it)?

Denoising? :)

The speed/noise difference may be exactly because of raySwitch (maybe no GI or other ray type is dismissed). There should be ways to have transparent shadows with rayswitch as well.
You can simply change the visibility (object properties) of the object. This should work in any case, with any material.

36

[Max] I need help! / Re: Long rendering time

« on: 2025-02-26, 13:51:44 »

Hi,

First, make sure the exterior windows have simple (thin) glass - this is a common user error that can significantly increase render times.
For the light sources, make sure they are easy to calculate - not inside a refractive object, not in a hard to reach path etc.

With just screenshots and not the scene itself, these are the only things that come to my mind. Full scene investigation will be the best thing.
Also make sure there are no strange environment effects in the scene - e.g. Fire Effect can kill performance very much.

37

[Max] I need help! / Re: How to brighten shadows in a white scenery?

« on: 2025-02-26, 11:54:01 »

Hi,

You are doing everything correctly. If shadow amount does not do the trick for you, try changing the material for shadow catcher, making it brighter, or tweak it using raySwitch.
Ultimately you need to control the opacity for the shadow, so you need to tweak the Alpha value (given that shadows are not full white or black) - this can be easily done right in the alpha channel of the image. You can either save it, tweak and then apply to the image, or you can tweak it directly as a channel inside Photoshop, if that is were the final compositing is going to happen.

Hope this helps.

38

[Max] Bug Reporting / Re: CBitmap - environment blur issue

« on: 2025-02-26, 11:33:11 »

Update:
There has been a major feature update - Differential Ray filtering - which solves this issue. Meaning scene extents do not affect the blurring/filtering seen through reflection/refraction.
Old scene will have the options (differential ray filtering) disabled, so they should be affected. Turning this option ON (this is the recommended state and new default) should solve it.
Upcoming daily build will have this feature in it.

39

[Scatter] I need help! / Re: Scatter one object on specific points. Plants, Lights, Furniture ... How to do ?

« on: 2025-02-11, 15:53:01 »

For relatively non-complex distributions, 3ds Max's array modifier (tool as well) can be very handy as well.
It just may have some limitations - e.g. CoronaLight cannot be arrayed with the modifier.

Scatter, of course, is another good way to do such things.

40

[Max] Bug Reporting / Re: Backplate + Sun causing shadow bug

« on: 2025-02-11, 13:07:43 »

It should be possible through rayswitch material, give it a try.

41

[Max] I need help! / Re: Weird problem, moving camera inside room cause changing materials on models :/

« on: 2025-02-06, 10:29:00 »

This looks like a medium resolving issue.

The best thing would be to check the scene. For now, you can at least make sure the windows looking outside have simple glass material, without any volumetrics/absorption, and thin option enabled.

42

[Max] I need help! / Re: corona lightmix and beauty pass have different saturations or rather color space

« on: 2025-01-31, 09:06:51 »

This has been fixed for a while internally. Next daily build will most probably have this in it.
Please give it a try when it is out. Note that some tiny difference may still be expected, but there won't be a difference as in the original images posted.

(Report ID=CMAX-1402)
(Report ID=CMAX-22)

43

[Max] I need help! / Re: Is it possible to make an OSL shader that rotates a color map?

« on: 2025-01-31, 08:59:50 »

Yes, but I still have to use 16 maps if I want to use 16 helpers. My initial idea is to use only 1 map and make the rotation procedural in the Shader, because I want to use that single map in 16 different sectors independently with different rotation.

What about a multimap node, e.g. CoronaMultiMap?

44

[Max] I need help! / Re: Batch render 100 of products with 50 different materials and colors.

« on: 2025-01-30, 21:16:22 »

What you are describing seems to be doable even with animation (keyframing the changes) and batch render, for different cameras.
But for a more comprehensive approach, I am yet to find a more comfortable (and reliable) way of doing this than the native (while not user friendly) scene states.
I believe all render managers use it or its functionality to do the versioning tricks.
The important thing is the scene states are supported by batch render, and render presets (settings) as well.

45

[Max] I need help! / Re: Is it possible to make an OSL shader that rotates a color map?

« on: 2025-01-30, 10:33:28 »

Hi,

I believe wire parameters is the thing you are looking for.
It is still not fully clear to me, but a triplanar map, which can rotate the texture based on a node, should work with OSL too. It may be worth a try.