Chaos Corona Forum

General Category => Gallery => Topic started by: Alcor on 2014-03-06, 22:04:36

Title: First Corona Test
Post by: Alcor on 2014-03-06, 22:04:36
Hi everyone,

Here is my first test on this amazing renderer.
I take an old vray scene, try to recreate all materials and keep the hdri (vrayhdri) for the environment
PT + HD, PTS 64, MSI 100 (precomp density 2 and max records [k] at 2000).
57min - i7 2600k

Title: Re: First Corona Test
Post by: Dervish on 2014-03-06, 22:26:42
Books books and books!.

Nice image.

For me that wall texture seems odd, maybe those lines are to repetitive.

I See Paraty house in that open magazine. :)

I think PT at 32 and a lower msi would have given you more passes and maybe less noise??
Title: Re: First Corona Test
Post by: Alcor on 2014-03-06, 23:36:11
My first "first" render was with PT+ HD and all default settings (pt 16 - msi 20) it was not so bad but a lot of noise (in the reflections especially).
I tried different settings and the best result comes with a higher msi value (and maybe with max records too).

I think I have read somewhere that for interior pictures it's better to use a high msi (200 ?) and for an exterior, a lower value is enough (40).

But I'm still at the beginning of my Corona's Adventure, so we'll see ! :)


Title: Re: First Corona Test
Post by: Alex Abarca on 2014-03-07, 01:25:48
thats nice, how did you make the floor?
Title: Re: First Corona Test
Post by: karazinsky on 2014-03-07, 07:17:40
That floor is totally awesome!:)
Title: Re: First Corona Test
Post by: Alcor on 2014-03-07, 21:19:19
Hi,

Here is my floor material Alex. :)
(The black&white map is use in reflection and glossiness slots)
Title: Re: First Corona Test
Post by: Alex Abarca on 2014-03-07, 23:43:04
Oh wow...your IOR is pretty high, but in the image your floor looks perfectly Reflect/glossy, not too much... not too little. Its just right!
Title: Re: First Corona Test
Post by: Alcor on 2014-03-09, 11:21:43
:)
Yes, I have a high IOR for that material. I'll try too explain that.

First, I've found on some sites (viscorbel and others) a small list of IOR (reflection) for some materials and all compound materials (wood, stone, concrete,...) are between 3 and 6 IOR. (water 1.33, glass 1.5 to 1.8, metal 20 to 100).
So, I have some numbers now.

Next, it's understand how the IOR (reflection) is working. For that, I've found on another site (Neil Bevlins) a lot of explainations about that.
And, the lower your IOR (reflection) value is, the less you will have reflection in front of the object (but you will have reflection on the side). And with a higher IOR value, the more the reflection will be uniform.

Best example is the glass.
When you're front of  a glass, the reflection is very low but if you look the same glass on the side you will see more and more reflection (depending of the angle).
For woods and others compound materials the reflection is less influenced by the angle.

So that's why I use higher value than usual pour my wood material.


p.s.: English isn't my mother language, so I hope I'm understandable and I hope too these explanations will be useful for others.
Title: Re: First Corona Test
Post by: subpixelsk on 2014-03-09, 12:17:16
Thanks for this explanation, do you by any chance have links to those sites with list of IOR numbers?
Title: Re: First Corona Test
Post by: Alcor on 2014-03-09, 19:48:04
Thanks for this explanation, do you by any chance have links to those sites with list of IOR numbers?

It's not a real complete list, just few words but here is the link
http://viscorbel.com/vray-materials-theory/ (http://viscorbel.com/vray-materials-theory/)

For the lazy
"
water 1.33
plastic 1.45
glass 1.5-1.8
diamond 2.4
compound materials like wood, stone, concrete etc 3-6
metals 20-100

Exact values need to be fine tuned for each material to achieve the right look.
...
"
Title: Re: First Corona Test
Post by: Alex Abarca on 2014-03-10, 03:23:12
:)
Yes, I have a high IOR for that material. I'll try too explain that.

First, I've found on some sites (viscorbel and others) a small list of IOR (reflection) for some materials and all compound materials (wood, stone, concrete,...) are between 3 and 6 IOR. (water 1.33, glass 1.5 to 1.8, metal 20 to 100).
So, I have some numbers now.

Next, it's understand how the IOR (reflection) is working. For that, I've found on another site (Neil Bevlins) a lot of explainations about that.
And, the lower your IOR (reflection) value is, the less you will have reflection in front of the object (but you will have reflection on the side). And with a higher IOR value, the more the reflection will be uniform.

Best example is the glass.
When you're front of  a glass, the reflection is very low but if you look the same glass on the side you will see more and more reflection (depending of the angle).
For woods and others compound materials the reflection is less influenced by the angle.

So that's why I use higher value than usual pour my wood material.


p.s.: English isn't my mother language, so I hope I'm understandable and I hope too these explanations will be useful for others.

I dont doubt it, Its looks great and you got it just right. Thanks for the explanation!