Page 1 of 1

Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 2:40 am
by RSgraphics
Hello.

Im trying to render out a chrome cube and it has displacement material. Im using a 32Bit LAYERED Tif as the displacement image. Also in the materials displacement setting, im using "Follow Geometric Normal", "Level of Details = 4096", I blured the edges in photoshop on the TIF to try and round/bevel the edges of the displacement.

But all of this leads to the horrible noisy edges and jagged reflections. Here are my render settings:

OTOY RENDER SETTINGS.PNG

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 5:32 am
by niestudio
I don't know about the displacement. Perhaps this is pushing the limits there, and it's something that should be modeled instead.
For the fireflies, if this is the same scene you posted the other day:
1. update your hdr by loading it into an image texture node instead of c4d bitmap.
2. in render settings, drop your GI clamp down to 1
You may not need adaptive sampling after this, but if so, you can increase the samples much higher when using AS. The idea is that it will stop rendering selective areas when they are deemed clean enough, and then focus on the other areas. 4000 samples is probably not enough to meet those thresholds.

You shouldn't need 20 for diffuse when rendering chrome.
Watch this video on finding the right settings for your scene
https://vimeo.com/124066262
hdr.jpg
Live_Viewer_3_08.jpg

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 8:51 am
by bepeg4d
Hi RSgraphics,
note that you need to change the Channel format to Float or Auto, to work with real 32bit displacement.
The Half value corresponds to 16bit pixel depth:
93A5A9EE-8B55-45EE-A88C-2D7CCE8DC465.jpeg
ciao Beppe

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 5:58 pm
by RSgraphics
niestudio

Thank you for catching the need for an Image Texture node. I fixed it here (see screen shot).

However, I have a question. If I'm using an HDR or EXR should the "TYPE" still be set to normal or should I change it to something like "Float"?

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 6:05 pm
by RSgraphics
bepeg4d

I changed my "BITMAP" node to an "ImageTexture" node. Thank you.

1, Please see screen shot. Should I make both the "TYPE" and CHANNEL FORMAT" to "Float"?

2. Also, if I'm using 32 bit black and white images for overlays (scratches, smudges) should the "TYPE" and "CHANNEL FORMAT" be set to "Float" as well?

3. One last thing, I can't achieve rounded corners with this Displacement. I've blurred the image in photoshop but the effect doesn't show up very well. Isn't their a way to adjust the "Blur Offset" and "Blur Scale" to achieve the rounded edge effect?

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 6:26 pm
by niestudio
RSgraphics wrote:niestudio

Thank you for catching the need for an Image Texture node. I fixed it here (see screen shot).

However, I have a question. If I'm using an HDR or EXR should the "TYPE" still be set to normal or should I change it to something like "Float"?
You'll want to stick with Normal here. Float would change it to black and white.

Type for your scratches etc can safely be set to float as they are just driving roughness which uses B&W

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jun 25, 2018 7:14 pm
by RSgraphics
niestudio wrote:
RSgraphics wrote:niestudio

Thank you for catching the need for an Image Texture node. I fixed it here (see screen shot).

However, I have a question. If I'm using an HDR or EXR should the "TYPE" still be set to normal or should I change it to something like "Float"?
You'll want to stick with Normal here. Float would change it to black and white.

Type for your scratches etc can safely be set to float as they are just driving roughness which uses B&W

Thanks Niestudio, I'll make sure to take note of that.




Also, bepeg4d, if you can, will you please respond to my response to you?

Re: Lots of funky reflections on displacment also fire flies

Posted: Wed Jun 27, 2018 10:50 am
by bepeg4d
Hi,
have you tried to play with the Filter type and radius, in the displacement node?
About 32bit displacement, you need to set the Channel format to Float, to work in 32bit, Half is for 16bit.
ciao Beppe

Re: Lots of funky reflections on displacment also fire flies

Posted: Fri Jun 29, 2018 6:16 pm
by RSgraphics
Hi Bepeg4d

Yes i understand. "Channel" has to be set to float or auto to work with 32 bit images.
However, what about "Type", does that have to be set to float?

Also, can you confirm that i use the "Filter" to blur the image slightly to get soft beveled edges? I thought I was suppose to use "Blur" and "Blur Offset".

I would just check this myself instead of just asking you, but i can't at the moment because I'm having GPU driver problems.

Re: Lots of funky reflections on displacment also fire flies

Posted: Mon Jul 02, 2018 10:14 am
by bepeg4d
Hi,
the Channel format is relative to the depth, while the type is relative to the channels, so you can define if to consider all the color channels (Normal), consider it as Black & White (Float), or take into consideration only the Alpha channel (Alpha). So it depends on the file used.
The Filter parameter is used to blur the displaced image, you can choose between Box and Gaussian.
ciao Beppe