Displacement grey level artefacts Tweet

[Tigersan]

Hello, I create muscular characters, therefore my work in octane is heavily dependent on displacements. I have a problem.
As much as I like the displacements in octane because they allow to both indent and extrude, it does lower the amount of
greyscale colors to portray extrusion or indention by half. Meaning 127.127.127 being the neutral 0.0.0 being the indention max
and 255.255.255 being the extrusion max. That presents a problem in form of lines on the rendered model that go along the
borders of each greyscale color representing another extrusion level - just like on the pic i attached. You can see weird lines
along the veins, and other extrusion or indentations.

Height is set to 0.02
Offset to -0.01

Anyone has an idea how to make this issue go away, without decreasing the value of displacement (but it doesnt really
make the issue go away). Maybe in ver 3.0 Octane guys can modify the algorithms to actually soften the color boders somehow.
I'm not sure im not an engineer. But I tried different formats to avoid compression because at first that was what i thought
caused it. But this render was made with all textures being used in PSD format. So I'm at a loss. Please help

[face_off]

This looks to be an issue with the displacement map source bitmap. Does the displacement map show these lines? Have you tried using a HDR bitmap rather than a LDR bitmap as the displacement source in order to get a finer level of detail?

Paul

[Tigersan]

Any bitmap will show the differences in the grayscale if you zoom in enough. You only have 255 greyscale levels afterall...

My displacement texture is painted by hand on my tablet. So theres no source. This happens even if i blur it to the point the
details are almost gone, but those lines still show, no matter what format i use... What do you mean HDR? in HDR white is still
255.255.255 all the same as LDR and black is the same 0.0.0... So I dont understand. If you use a gradient smoothly translating
from 0.0.0 Black to 255.255.255 white you will be able to see those lines along the borders of EACH color... Octane makers
probably didn't consider using displacements on the bodies in the extensive way I'm using them. But as Octane is supposed to
be creative program, this limits the creativity :/ I dont have to zoom in that close but i want to be able to, and not be limited
by my software.

Plus I never had an issue like this on ANY other rendering engine... I love Octane but I wish they fixed that.

This diagram illustrates what i mean. No matter if its the HDR or LDR you still have 255 greyscale levels no more no less.
My point is the rendering engine should have a way of softening the differences between colors not treating them like blocks.

[face_off]

Any bitmap will show the differences in the grayscale if you zoom in enough. You only have 255 greyscale levels afterall...

You have 65000 greyscales if you use a HDR image (such as .HDR or .EXR).

Paul

[Tigersan]

My point is, other programs dont have a problem like it.

[Liketheriver]

Hi Tigersan,
Try with 16 bit (or 32 bit ) images, like tiff, or exr, like mentioned above, but you need to paint them directly in 16/32, convert an existing 8 bit image don't work.
The best way is to sculpt the detail in zbrush and bake them in 16 bit

LTR

[Tigersan]

Sorry that I got quiet for a while, but instead of arguing about something I obviously had no idea
about I just went and tried it out... And it worked!!! I didnt even have to repaint my old displacements.
I just converted them to 16bit/channel in PS and did gaussian blur value 2, and it removed all the
unwanted artefacts, and kept most of the neccessary detail crisp. Saving them in PNG format was
enough to get rid of the issue i had... So I just wanted to thank you guys for always being helpful
with your advice and experience!