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Displacement banding problem

Posted: Fri Jan 25, 2019 8:40 pm
by Labrats
Hi,

I have a small issue here. For a job I need to create a landscape animation.
I'm exporting a 8K 32-bit TIFF height map out of world creator. Having it imported in cinema 4d and rendering it out with octane (displ settings 8K) i'm getting the results you can see in the attached image. If you look at the closest part of the mountain, you see a lot of artifacts. These are called 'banding' artifacts, and they are caused by using a image that has a bit-depth that is too low, for example an 8bit jpeg. However Like I said earlier, I'm using a 32bit TIFF. I tested this TIFF out on vray, and there it worked like a charm. All detail was perfectly visible and no banding. Any idea what's causing this in octane? I tested all kinds of other formats (RAW, EXR, PNG, etc) and even other bit depths. they all give me the same artifacts. With lower bit depth, the banding is worse (which is normal i think).

Any ideas?

Kind regards,
J

Re: Displacement banding problem

Posted: Sat Jan 26, 2019 3:39 pm
by niestudio
See here

Re: Displacement banding problem

Posted: Sat Jan 26, 2019 3:54 pm
by frankmci
If the referenced thread doesn't answer your question, you'll get better responses if you can post a small example scene exhibiting the behavior, along with system details. Good luck!

Re: Displacement banding problem

Posted: Sat Jan 26, 2019 7:44 pm
by Labrats
Hi there,

I tried the solutions on the thread, to no avail. I'm using Octane for c4d, V.4.01.1 on windows 10, using I7 3960X, 32 GIG ram. C4d is R20.
I attached a scene file with another exported displacement from another landscape in world creator, this time using a 16bit TIFF in 4K, so the scene file wouldn't be to big to upload. On my system, same problem with the bending. The strange thing is, when i'm using an 8K map, the banding is even worse (it looks sharper and bigger).

Hope anyone can help me out here. The problem is, I can't use displ this way, and that's kind of the whole point of this job :-)

Kind regards,
J

Re: Displacement banding problem

Posted: Sat Jan 26, 2019 9:58 pm
by frankmci
That example scene inspired me to dig deeper. I'm afraid I can't solve your problem, but after looking into it, I can share a bit of info that might lead the developers to a solution: The displaced geometry is fine, but the surface normals are way off.

Here's a quick test I just did in C4D R19, Octane 4.01.1-R2, using an 8k 32bit black to white linear ramp .TIF as the source displacement texture on a simple plain, with the Displacement Level of Detail also set to 8192. Notice that the actual geometry generated by the displacement is correct, but the surface normals are significantly lower resolution/sampling rate. I tested the surface res of these closeup images with an 8k black and white, single pixel per check, checker pattern (seen on the right) in the diffuse to be sure of the geometry resolution, as well. Click to see full size.

I hope that's helpful.

Re: Displacement banding problem

Posted: Sat Jan 26, 2019 11:39 pm
by Labrats
Thanks for that frankmci! I hope the devs will look into this, would be awesome if I can use displ again for my landscapes. One weird thing tough, I never noticed this on earlier versions of Octane. But that's probably because I only used displacement for more techy/greeble stuff.

Re: Displacement banding problem

Posted: Sun Jan 27, 2019 12:14 am
by aoktar
Labrats wrote:Thanks for that frankmci! I hope the devs will look into this, would be awesome if I can use displ again for my landscapes. One weird thing tough, I never noticed this on earlier versions of Octane. But that's probably because I only used displacement for more techy/greeble stuff.
You need to change "texture import type" to 32bit. But this tiff is mono 16bit and I think it's not recognised well and proper options not displayed correctly.

Re: Displacement banding problem

Posted: Sun Jan 27, 2019 1:49 am
by Labrats
Hi Aoktar,

Thx for your answer. Can you elaborate what you mean by a "mono TIFF"? The TIFF you talking about comes right out of world creator and should be fine. At least in Vray it is.

Also, there is no option ""texture import type" in my settings, see video in attachment (there I used a 32 bit 8k version of the file). There are 3 other options, but when I select one of them, Octane freezes (you will also see this behaviour on the video) Wich octane version do you use? I'm using 4.01.1.


Kind regards,
J
Capture.mp4
(29.17 MiB) Downloaded 3857 times

Re: Displacement banding problem

Posted: Sun Jan 27, 2019 3:03 am
by aoktar
Labrats wrote:Hi Aoktar,

Thx for your answer. Can you elaborate what you mean by a "mono TIFF"? The TIFF you talking about comes right out of world creator and should be fine. At least in Vray it is.

Also, there is no option ""texture import type" in my settings, see video in attachment (there I used a 32 bit 8k version of the file). There are 3 other options, but when I select one of them, Octane freezes (you will also see this behaviour on the video) Wich octane version do you use? I'm using 4.01.1.


Kind regards,
J
Capture.mp4
Options you see, these are for 8bit images. As I said there's a wrong detection for grayscale tiff you use. I've fixed it for correct options for V4.02. Please check image again for LV's title text.
Find it here: viewtopic.php?f=85&t=70479

Re: Displacement banding problem

Posted: Mon Jan 28, 2019 12:18 pm
by Labrats
Hi Aoktar,

That update fixed it. Thank you very much for your time and effort!

Kind regards,
J