Author Topic: How to get my corona sky this type of blue  (Read 21712 times)

2016-11-06, 15:25:44

Jadefox

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Hi Guys

I was browsing the gallery and came upon an old post by Spike Spigel ( think his name is Sergey ) https://forum.corona-renderer.com/index.php?topic=6021.0
I was just blown away by the realism. He states its nothing more that Corona sun and sky and I read in the comments that he uses a color correction on his corona sky. I tried my best to recreate this but always end in a dirty blue sky. I have also contacted him but I suppose he is not so active on the forums anymore.  Can anybody please assist me in explaining to me how I can recreate this rich blue sky

I would appreciate so much !!

Regards

2016-11-06, 18:13:16
Reply #1

maru

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I think he only used Sun+Sky for lighting, so the background may be something else.
Marcin Miodek | chaos-corona.com
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2016-11-06, 19:53:14
Reply #2

Jadefox

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Hi Maru

Thanks ,I see what you mean
I've put an HDRI in environment override and I think it closely resembles his background

Thanks for the advice

2016-11-06, 20:15:53
Reply #3

Ludvik Koutny

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I don't see any reason why it could not be CoronaSky on Spike Spigel's renders. It's just a blue gradient after all, exactly what what CoronaSky is.

2016-11-07, 07:21:37
Reply #4

Jadefox

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I've tried the color correction node Rawalanche

1. Increase saturation
2. Decrease gamma
3. Set the intensity of corona sky

( I am sure the above is not correct, it was just the only way I could try and simulate that type of blue )

But it always comes out, almost dirty and not that rich blue , I'm attaching screen shots to explain better

Regards

2016-11-07, 09:23:47
Reply #5

fellazb

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I think that the green colours of the grasses and especially the trees and the dark facades of the house gives the sky that nice blueish vibe. If you make testrenders with a white scenery than it's just what it is.

My suggestion would be to add more vibrance to your scene and not worry that much about the sky intensity first.

2016-11-07, 12:38:49
Reply #6

Cheesemsmsm

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Is this what you are after?


2016-11-07, 12:39:43
Reply #7

romullus

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You will never be able to get rich deep blue sky unless your enviroment is underexposed a little bit. Instead of trying to colour correct enviroment and potentially messing with scene lighting, i'd suggest you to use direct override or even replace sky in post processing stage.
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2016-11-07, 16:05:05
Reply #8

Ludvik Koutny

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Actually, you don't even need to underexpose as long as your scene is dark to start with. Like the black house and darker foliage around it in the link above. You will often get that rich blue sky especially when sun is very high above horizon. I guess he just rendered nice linear images, and then did some postprocessing in PS to boost contrast. That's most likely what pushed CoronaSky into those more rich tones. Color correcting in right in the environment slot is a nonsense.

2016-11-13, 18:46:32
Reply #9

vkiuru

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Color correcting in right in the environment slot is a nonsense.

You're big on having the UI as tidy as possible. If correcting a background to be more appealing is nonsense then in what scenario do you see Direct visibility override as valuable? I'm genuinely interested because back in the day I remember comping skies to Vray renders where, IIRC, I used a black environment color in the render so the tree etc edge pixels would be correctly fixed and ready for comping, otherwise there would be artifacts. I've forgotten the right technical wording. Is this still something to consider in Corona?

2016-11-15, 23:42:54
Reply #10

Alex Abarca

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I dont think is nonsense, i think hes using the tool as intended.

 Maybe its just me, but the sky system is a bit overexposed in corona when rendering with default values (just the sky color).

2016-11-16, 10:13:05
Reply #11

Frood

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Maybe its just me, but the sky system is a bit overexposed in corona

Agree, I feel the same.

Good Luck


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2016-11-16, 11:45:07
Reply #12

maru

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Maybe its just me, but the sky system is a bit overexposed in corona

Agree, I feel the same.

Good Luck
Isn't this just because the model assumes that sky is completely clear? It's like a supper sunny day with no clouds.
Marcin Miodek | chaos-corona.com
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2016-11-16, 12:52:18
Reply #13

Frood

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Don´t know what the model assumes, but when I compare photos (clear sky, unmodded) with standard corona sky renders, it´s allways too bright compared to the rest and thus too washed out, even when the effect depends drastically from day/time.

But maybe the rest of my scenes is just too dark :) Cannot substantiate this any further, sorry. And since 1.5 I additionally have the feeling that the standard exposure for a cSun+cSky setup went from -3 to -3.5 for some reason.

I would setup many scenes by lighting with cSky + cSun but have HDRI in visibility override and reflection override. But as long as this exists it´s just not possible to do this reasonable.

Good Luck

Never underestimate the power of a well placed level one spell.

2016-11-16, 15:08:09
Reply #14

romullus

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Curious at which sun angles you get away with EV -3 -3.5? I have toolbar button that creates sun at ~55 angle, adds sky to enviroment and sets EV to -4. If i set EV to -3, then for clear unobstructed outdoor shots, my sun angle should go to 70-75 degrees, which is basically sunset-sunrise already.

And i didn't notice change in sky brigthness from 1.4 to 1.5. Might it be due to changes in materials (new PBR)?
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