TEXTURE INACCURATE

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skip
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Joined: Mon Feb 28, 2022 4:31 pm

TEXTURE INACCURATE

Post by skip » Tue Mar 01, 2022 4:23 pm

Why is the granite (grey texture) so different on my rendered model?Image
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Screen Shot 2022-03-01 at 10.16.22 AM.jpg
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Chris
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Re: TEXTURE INACCURATE

Post by Chris » Wed Mar 02, 2022 6:02 pm

Your index of refraction (IOR) is way too high.

If you want a typical polished concrete, it's probably in the 1.5 range. You would very rarely go over 2.0 for any material and never below 1.0 for any real-world material.

skip
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Re: TEXTURE INACCURATE

Post by skip » Thu Mar 24, 2022 6:02 pm

I had no success with those numbers.
Had to go much higher.
I would add a photo, but for some reason when I click on the photo icon I get this
Image

Fletch
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Re: TEXTURE INACCURATE

Post by Fletch » Thu Mar 24, 2022 6:29 pm

IOR would be the index of refraction. So IOR at 10, you have made it similar to metal.

Increase the shininess to 2000 to make it very shiny, but leave the IOR at that of real granite, around 1.3-2.5. Or you could use the Perfect Reflection template to quickly make a polished granite look - try 'Perfect Reflection Medium" to start. I use that for granite countertops.
IOR for
Diamond is 2.418,
Pyrex is 1.474

List of IOR for many materials here

so granite must be somewhere in there, right?

to attach an image use the "Attachments" tab under your message on this board where it says "preview/submit" below.

skip
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Re: TEXTURE INACCURATE

Post by skip » Tue May 31, 2022 3:04 am

I tried what you suggested, but the result was not what I would call shiny granite. I tried using stone/gloss template, and plastic shiny template with no result that showed a shine. Only way I got shiny granite was to use glass which was too much .
Here's my result using plastic shiny template. The stone/gloss template was the same.
Image[/img]
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Screen Shot 2022-05-30 at 9.58.43 PM.png
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Fletch
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Re: TEXTURE INACCURATE

Post by Fletch » Tue May 31, 2022 2:00 pm

You should use a spherical sky instead of this geometry dome with photo applied that you appear to be currently using.

The stone material is clearly shiny, and reflective. Not sure exactly what specific material you're going for here, (maybe attach a photo example) but you can clearly see the reflection of the man on the right in the shiny stone.

When you are rendering a shiny surface, it's very important that the environment be correct, and the angle of the camera is also important for catching reflections.

If you want a more polished surface, maybe increase the shininess (double it).

Try lighting with HDR spherical sky, and find higher quality Tree and vegetation models.

skip
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Re: TEXTURE INACCURATE

Post by skip » Tue May 31, 2022 3:02 pm

that WAS using a spherical sky (see screenshot above)
also, I added a light to simulate a skylight to light up the breezeway, but it didn't seem to have any effect.
see attached
Screen Shot 2022-05-31 at 9.58.21 AM.jpeg
Screen Shot 2022-05-31 at 9.58.21 AM.jpeg (569.04 KiB) Viewed 3766 times

Fletch
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Re: TEXTURE INACCURATE

Post by Fletch » Tue May 31, 2022 9:17 pm

Have you watched the 6 video tutorials linked in my signature?

The unrealistic vegetation models are not helping the image. There are better models available on the 3D warehouse and other places online.

Adding a light for that purpose will only cause it to slow the rendering as it tries to correct for errors being caused by the unnatural light.

My mistake in the spherical sky comment, it's that the sky is so dark in the rendering that something is strange, and makes it appear as geometry. I realize now that the screenshot you provided does show the spherical sky settings, and even stranger, you have the sky brightness set to 1.6.

Learning to create renderings does have a bit of a learning curve, be patient as you learn.

The spherical sky is going to cast light onto the model from all around, you should put a ground plane under your model and trees, as they are not getting lit up properly (light is shining up from the ground.) Paint the ground plane with grass, or a medium grey (50% grey).

Render test renderings at very high resolutions is going to slow your testing/tweaking phase down very much.
Render only small resolutions while testing. 800x600 or something like this.

The lighting should be adjusted with the Post Process tab. see this:
Subject: ACES vs Filmic : When do I use Filmic versus ACES when Tonemapping?
Image

skip
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Re: TEXTURE INACCURATE

Post by skip » Wed Jun 01, 2022 3:58 pm

yes, I have watched most of the videos. what brightness do you suggest on the sky?
I'll try a different spherical sky.
I plan on making 2 renderings, one without a grass plane so I can use the background trees and one with and blend the 2 together, then add a photo
of grass to the rendering
Meanwhile I'll look for a bighter spherical sky.

skip
Posts: 115
Joined: Mon Feb 28, 2022 4:31 pm

Re: TEXTURE INACCURATE

Post by skip » Wed Jun 01, 2022 4:28 pm

I"m trying to import an HDR spherical sky but seems its not available
Screen Shot 2022-06-01 at 11.27.48 AM.png
Screen Shot 2022-06-01 at 11.27.48 AM.png (821.67 KiB) Viewed 3738 times

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