Author Topic: Color correction + light balance  (Read 703 times)

2020-01-19, 12:59:55

moalfaraj

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Hello Everyone,

I've been using Corona for a couple of months now and i'm facing an issue that i don't know how to fix. i've noticed that there's a difference in color in different angles. for example i would apply a single wall paint color but i noticed it looks different from angle to angle. is there a color correction function built-in 3DS Max to fix this? also i noticed the lighting is not balanced. is there a way to balance the outside lighting with the outside lighting? i'm using HDRI as a lighting technique. i've attached some images for you to see


Thanks!

2020-01-20, 10:00:19
Reply #1

GeorgeK

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I am guessing you are referring to the walls? Can you please provide a screenshot of the node structure of your material?
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2020-01-20, 13:34:02
Reply #2

moalfaraj

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yes, i am referring to the walls but also how to do color correction in max in general. i've attached the node structure, its taken from a corona preset material and been modified to get this color.

2020-01-20, 13:56:41
Reply #3

GeorgeK

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yes, i am referring to the walls but also how to do color correction in max in general. i've attached the node structure, its taken from a corona preset material and been modified to get this color.

Is there any coloration in reflection? what's the scale of your triplanar settings under the reference node?

Would help if you could upload the scene in an archive and send us to investigate, please consider using our uploader or dropbox if the file is too large : https://corona-renderer.com/upload
“Every artist was first an amateur”

2020-01-21, 16:41:18
Reply #4

maru

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Most probably the difference in walls depending on the viewing angle comes from their reflectivity. Removing reflectivity completely might help, but obviously would also change the appearance of those materials.
How a surface gets its "color" is quite complicated - you have to take GI, reflections, lights, other objects into account.
If you would like to negate the coloring coming from an HDRI, you can desaturate it.

2020-01-22, 08:14:49
Reply #5

moalfaraj

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I've uploaded the scene, it's named (Abdulrasool Al Nahash_INT)


Thanks!

2020-01-22, 08:21:06
Reply #6

moalfaraj

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Most probably the difference in walls depending on the viewing angle comes from their reflectivity. Removing reflectivity completely might help, but obviously would also change the appearance of those materials.
How a surface gets its "color" is quite complicated - you have to take GI, reflections, lights, other objects into account.
If you would like to negate the coloring coming from an HDRI, you can desaturate it.



yeah the color is satin. i'll remove the reflection and see if i get better results. in the meantime, you are welcome to check the scene and if you can give me some tips on how to improve it. i'm trying to improve the quality of renders and the scenes i am doing at work are pretty complex for me, so i'm trying to figure out the best way to light a scene.

2020-01-22, 12:52:25
Reply #7

GeorgeK

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Most probably the difference in walls depending on the viewing angle comes from their reflectivity. Removing reflectivity completely might help, but obviously would also change the appearance of those materials.
How a surface gets its "color" is quite complicated - you have to take GI, reflections, lights, other objects into account.
If you would like to negate the coloring coming from an HDRI, you can desaturate it.



yeah the color is satin. i'll remove the reflection and see if i get better results. in the meantime, you are welcome to check the scene and if you can give me some tips on how to improve it. i'm trying to improve the quality of renders and the scenes i am doing at work are pretty complex for me, so i'm trying to figure out the best way to light a scene.

Thanks for the scene moalfaraj some things to consider:

- I've noticed you are using a lot of light-select elements for light mix, did you try going one by one to see if there is a correlation with your reported issue?

- Please make sure the scale of your triplanarmap is correctly set for your scene, big scale numbers will result to strange shading artifacts due to the size of the original bitmap.

-Try collapsing all instanced modifiers of your walls and try please to fix the non-smoothed facets, you can either apply a smooth modifier or try auto-welding with very small distance threshold.

- Lastly if possible remove any missing plugins/scripts/anim.layers/garbagecollection/ from your scene, also delete or remove the deactivated vraylights from your light-select elements.

Try the above and please let me know if it helped or not.
“Every artist was first an amateur”

2020-01-23, 00:44:06
Reply #8

Njen

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I haven't had a look at the Max file, but after looking at the screenshot of the material, the colour being used in the diffuse slot looks awfully bright. Are you sure it's less that 0.85? 0.85 is an albedo for fresh white snow, one of the whites substances known, so no colour should be whiter than this.

For a white satin wall paint, I'd recommend somewhere in the range of 0.77 to 0.81. Any brighter than that and you will start to break the relationship with a physically accurate material.
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2020-01-26, 10:15:06
Reply #9

moalfaraj

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Most probably the difference in walls depending on the viewing angle comes from their reflectivity. Removing reflectivity completely might help, but obviously would also change the appearance of those materials.
How a surface gets its "color" is quite complicated - you have to take GI, reflections, lights, other objects into account.
If you would like to negate the coloring coming from an HDRI, you can desaturate it.



yeah the color is satin. i'll remove the reflection and see if i get better results. in the meantime, you are welcome to check the scene and if you can give me some tips on how to improve it. i'm trying to improve the quality of renders and the scenes i am doing at work are pretty complex for me, so i'm trying to figure out the best way to light a scene.

Thanks for the scene moalfaraj some things to consider:

- I've noticed you are using a lot of light-select elements for light mix, did you try going one by one to see if there is a correlation with your reported issue?

- Please make sure the scale of your triplanarmap is correctly set for your scene, big scale numbers will result to strange shading artifacts due to the size of the original bitmap.

-Try collapsing all instanced modifiers of your walls and try please to fix the non-smoothed facets, you can either apply a smooth modifier or try auto-welding with very small distance threshold.

- Lastly if possible remove any missing plugins/scripts/anim.layers/garbagecollection/ from your scene, also delete or remove the deactivated vraylights from your light-select elements.

Try the above and please let me know if it helped or not.


i'm not familiar withe triplanar mapping, i will look for it online, but if you happen to know a good tutorial do please share.
i also removed the reflection node and reduced the diffuse from 1 to 0.85, and i did get better results.
Thank you! really appreciate it