Messages

1

[Max] I need help! / Re: Strange behaviour when exporting EXRs (Corona 4.0 issue?)

« on: 2019-07-08, 11:48:57 »

Hi rowmanns,

thank you for the reply.
For anyone who faces this issue:

A quick workaround would be to open the EXRs in GIMP (you can keep them at 32 bits) and then (by using CTRL + C) to copy and paste them into PS. For some reason this keeps the color and gamma intact.. it is really strange.

We tried exporting PSDs from GIMP and also TIFFs with layers but these ideas also did not work (still wrong color, always 8 bit and so on), so we settled with this workflow. In the long term this of course highly unsatisfying, but for now it at least works somehow...

P.S. Affinity also has this problem.

2

[Max] I need help! / Strange behaviour when exporting EXRs (Corona 4.0 issue?)

« on: 2019-07-05, 10:10:52 »

Hi Coronauts,

We have come across a strange issue when opening EXRs that have been rendered in Corona 4.0. At least it seems to be related to 4.0, as we had no similar issues before.

Descripton:

My task is to render a set-extension for a photographed set (large wood beams on the ceiling).
No problem so far: camera-matching, light-setup, shadow-cather - everything worked as always and Corona's IR makes it very easy to see if what I was doing acutalley feels right.

However, when I finally rendered the Hi res version as CXR, wrote the EXRs from the CIE and then loaded them into PS, they looked wrong colorwise. Not completely wrong, just a little bit off.

You can clearly see the seam where the wrong color of the EXR meets with the real image. The real image has a lot more red in it and seems to have a bit more punch:




No matter what we tried (writing EXR directly from VFB, using different PS-versions and setups, renaming CXR to EXR), nothing solved this problem.

The only "usable" workarounds are: using JPG (which is obvously not an option) or using the CTRL + C option from whtin the VFB in order to copy the image directly into the photo.

This is how it should look like:



The strange thing is: GIMP does handle these files very well.

So the problem might be related to Photoshop, but it is unclear in which way and since these problems only occured since Corona 4.0, there  also might be some causality on the Corona-side.

Has anybody come across a similar problem so far? It is really strange und we did not change any of our PS-versions or settings...

3

[Max] I need help! / Re: Corona 3.0 Displacement Artifacts

« on: 2019-03-07, 10:29:29 »

The wall has a simple box-mapping applied, nothing fancy there.
In fact we had a case in which a wall with a relatively simple brick-texture applied to it(and chamfered edges) worked fine in 2.0 and had to be re-done in 3.0 - we deleted the chamfers and then it was ok (although I would consider this an unsatisfiying solution).
Unfortunately I cannot show these steps, as we did not save the image due to the corrupt geometry and currently we do not have the time to switch back to 2.0 to show exactly what I mean.
At that point we still considered it an isolated case.

I do agree with romullus, as an unnecessary subdivision might be an "ok-ish" solution, but seems redundant, especially as it worked fine before.

I attached the MAX-file of the wall including the textures, maybe you can have a look at it at some time.

4

[Max] I need help! / Re: Corona 3.0 Displacement Artifacts

« on: 2019-03-05, 13:32:09 »

I added some horizontal lines and the chamfered edges turn out a little bit better... Therfor another problem appears on the right flat side of the wall, which is really strange, as it does not seem to tesselate this simple geometry properly.
You can clearly see the new edges as artefacts in the displaced geometry, this has usually never been an issue before.
(I only attach the AO-pass, as the phenomenon is most prominent there).

5

[Max] I need help! / Re: Corona 3.0 Displacement Artifacts

« on: 2019-03-05, 11:14:45 »

Disableing AutoBump unfortunately does not do the trick, weirdly enough it was already disabled (although I did not alter any settings in dev/debug)...
Has nobody else come across this problem? Maybe for the most part it is not really visible when displacing large irregular surfaces like brick walls without a corner or uneven muddy terrain.

6

[Max] I need help! / Corona 3.0 Displacement Artifacts

« on: 2019-03-05, 10:09:08 »

Hi Coronauts,

in our company we just upgraded to 3.0 (including Hotfix) for 3ds Max and ran into an issue regarding the new displacement.
I tried to find a solution in the forum, but did not find any.

We always use chamfered edges on our walls in order to make them more realistic.
When using displacement, these chamfered edges will become the typical distorted geometry known from older methods of displacement.
I attached some images to show what exactly I mean.
I do not recall this issue from any project we did with 2.0.
So far this problem occured in two seperate scenes with different kinds of geometry, so it might be safe to say that it is a general problem.
Is there a quick fix for this problem?

7

[Max] I need help! / Re: Output-gamma cannot be changed

« on: 2017-01-26, 08:35:15 »

Hi Maru,

I already checked the correct Gamma-settings in the ini-file twice.
What is really strange is, that every modification in the ini-file does not effect the finale .exr-files. They always end up with having a Gamma of 1.0 except for the Beauty-pass, this always has the correct 2.2 (even when I set the output-gamma to e.g. 4.4).
This is also why I asked if Corona overwrites these values internally, as any modification of the ini.file does not seem to work for the final exrs.
This whole issue would be half as bad as it is, if Photoshop could the correct Gamma properly, but of course it cannot do it completely correctly.
As a work-around we currently have to open the exr-files in the Vray VFB, so that we cann add the Gamma there and export the file again.

Has anybody ever tested if altering the Gamma-value within the 3dsmax.ini really has an effect on the images?

8

[Max] I need help! / Output-gamma cannot be changed

« on: 2017-01-25, 14:24:12 »

Hey Corona-team,

as we do not make heavy use of render-elements anymore since using Corona, we did not bother much with making sure that all of them come out completely correct.
As of today we wanted to use the Reflect-element for composing and noticed that its gamma-value was not 2.2 but 1.0 despite having a working 2.2 in the Beatuy-pass.
Afterwards we became sceptical and noticed that only the Beauty-pass had the correct 2.2, all the elements have 1.0. This is just an issue when using the "save"-button of the Common-tab in the render-dialogue.
When saving the files directly from Corona VFB, the Gamma-value will come out correctly.

I tried different things concering the Gamma-value (using values of 4,4 in display, input and output gamma in the max-ini, disableing Gamma completely) but the phenomenom strangely stays the same:
The Beauty-pass has a working 2.2, the elements only 1.0, just like it would not be affected in any way by the modified Gamma in the ini-file.
It is very strange and I wonder if something gets overwritten by Corona internally, so that this happens all the time...


3ds max: 2017
Corona: 1.5

9

[Max] Resolved Bugs / Re: Corona VFB switches to black

« on: 2016-12-01, 08:34:12 »

hi,

I rendered the frame over night without the VFB Post-FX and it managed to get to nearly 200 passes without a black VFB.
I stopped it and could save the image. As soon as I turned on Bloom and Glare the VFB became black again, all other FX seem to work fine.
At least you gave me the right direction if this occurs again, thanks a lot.
I still find it strange and of course we want to use Bloom and Glare from time to time.

Is there any advice how to avoid this behavior? I just want to make sure that we can use VFB FX without being worried that the picture will turn into black.

@ Ondra: Corona is 1.5.2 (but it also happens in 1.5.1). The scene is around 200 Mb large, no scattering, no proxies or any other fancy stuff.

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[Max] Resolved Bugs / Re: Corona VFB switches to black

« on: 2016-11-30, 15:36:58 »

I was using a lot the VFB-features.
I will try turning off all of them and see what happens. I will post an update as soon as I see anything strange.

11

[Max] Resolved Bugs / Re: Corona VFB switches to black

« on: 2016-11-30, 15:15:15 »

Hi,

I wanted to save them as .exr but also tested .tiffs, does not make a difference.
I have 48 GB of RAM and the scene is relatively simple, It took around 7 GB of RAM.
As I said, I already tried it via backburner or DR, picture still turns black.
There are no Corona-errors whatsoever which is the strangest thing.
As I had to try several things, I noticed that Corona will not render more than a certain amount of passes (e.g. 27) within one session before the VFB turns black. This is why I had to restart MAX and give it another try. In a new MAX-instance it will render past the level of passes which caused the black VFB.
Veeeery strange.

12

[Max] Resolved Bugs / Re: Corona VFB switches to black

« on: 2016-11-30, 13:04:37 »

Ok, seems like no one ran into this before.
Just if anybody experiences this problem:
So far the only way to at least get the files out of the framebuffer is to keep an eye on the FB and save the VFB every ~ 10 passes or so. When the VFB turns black again, close the file, restart MAX and resume the renderjob from file.
It is not very fun to do this, but at least it works.
I am still interested if there is anything to prevent this, we do not have this issue with any other file.

13

[Max] Resolved Bugs / [feedback] Corona VFB switches to black

« on: 2016-11-29, 10:22:28 »

Hi @ all,

I have encountered a strange behaviour in Corona 1.5 (1.5.1 and 1.5.2) with 3ds max 2017 SP 2.
I rendered a Hi-res image (4900 x 3500 px) and when starting the render process everything is fine. After 30 passes or so, some of the render elements (including beauty, lightmix and reflect/refract) turn black. When scrolling through the elements, they will be visible again, but will disappear after a second or so. When I try to save the .exr files, they will turn out completely black. I hoped that it would be just a display issue, but the image itself does not contain any information except black.

I already made a completely new file, tried it only locally, with DR and via backburner, it is always the same. There are only Corona-compatible cameras and materials inside the scene and the camera is not occluded by any other geometry.

Any ideas how to fix this? I did not encounter anything similar so far

14

[Max] I need help! / Re: Strange behavior when rendering interactively

« on: 2016-09-30, 17:29:28 »

Maybe eventually IR will start showing a picture, I waited around a minute or so and often decided to abort it, often times even crashing 3ds max.

The t-shirts were models which we bought some time ago from http://www.viz-people.com/
They seem to be simulated meshes, but they are heavily optimized before export, so that they do not contain any really heavy geometry.
My collegue did not use any models from this collection, when he encountered this problem, so this collection is not even something I could point my finger on. It is all very strange.

The material itself is really simple, just a Falloff in the diffuse-slot and a little bit of reflection (not even bump).

Maru, I sent you a PN with a download-link for the problematic scene. The shelf-system has been removed, as it was the product of our client, the problem is still persistent. I am really corsious, if you encounter the same issue.

15

[Max] I need help! / Strange behavior when rendering interactively

« on: 2016-09-30, 09:38:32 »

hey guys,

I am writing regarding a strange issue we came across during the last two productions, both times we encountered the same behaviour.

The situation:
In our studio, we do ArchViz (using 3ds max) and use a lot of High Poly props (Some scenes have around 15,000,000 polys in just one room).
So far, Corona could handle even this amount of polies even in interactive mode (and sometimes even with Hair and Fur enabled). Of course it took a while to get an image, but it was okay working this way and of course it is much better compared to Vray (we did not even bother using RT there, it was just too slow).

In the last production, I had to visualize a room with a lot of clothing. After merging a certain type of 3d-model from our stock (some T-shirts), I could not use Interactive mode anymore. Well, I could still press "Interactive" and Corona tried to start it, but no image came up. I looked at the task-manager and noticed a strange bahaviour (you can see a screenshot attached). Basically the processing power and the RAM go up and down, but the CPU never reaches a constant high, like when it is rendering. At the time I blamed the 16 GB of RAM and simplified the scene until I got it working again (that was not very fun, I had to check every prop, until I found out that the T-shirts were causing the trouble). The strange thing is, that the T-shirt material seemed to have caused this, although it was not very complex. I created a new one from scratch and this one worked again.

Anyways, yesterday we got an upgrade from 16GB RAM to 48 GB RAM and I was eager to see if I could get this scene working now. But still, it was the same issue, just without the Corona-warning, that I am running out of RAM. My collegue also encountered the same behaviour in another project which was completely unrelated to mine. If this problem was just on my machine, I would have blamed it on the file, but in this case, I am starting to get a little nervous. Is this something, anyone has come across so far?

We are using 3ds max 2017, newest SP and newest Corona Daily Build.
I also checked the file in 3ds max 2016, Corona 1.4, same problem...