Author Topic: incorrect alpha with opacity  (Read 2287 times)

2023-03-09, 15:02:46
Reply #15

Tok_Tok

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I sometimes use the Opacity setting to get the effect I want. But usually I change the IOR or the reflectiveness. In both cases I get a wrong alpha map.

But as I stated before, even if I save the alpha channel to a file, I get a different image than the VFB shows me. So I think the problem is in the saving.

2023-03-10, 14:16:22
Reply #16

maru

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If the background color in the target document is going to be similar to the one in 3ds Max, then this is the best I could come up with:

0. Our end goal is to get a result similar to the Corona VFB.


1. Enable direct visibility enviro override and set it to black.


2. Add a CMasking_Mask render element, include all objects in it, scroll down and disable "allow propagation".


3. Render and inspect the Beauty element. It should look like this.


4. Inspect the Mask element. It should look like this (all objects are solid white).


5. Save in any format, without alpha - I used PNG (settings attached).


6. Load both files into Photoshop. Apply the Mask to the Beauty. Save as PNG.


7. Load into PowerPoint.



Marcin Miodek | chaos-corona.com
3D Support Team Lead - Corona | contact us

2023-03-13, 10:00:43
Reply #17

Tok_Tok

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Oke yes I got this far, but where is my semi transparent alpha channel? I know I can use a mask in corona to single out objects but I need something that allows for half transparant pixels that give me the same result in photoshop as it does in the VFB.

Check the alpha channel of the render you just showed me, I need that map to give me the same results as in photoshop. As or right now it doesn't and frankly this is either a bug of corona has gone down hill since Chaos Group got involved. I'm a bit frustrated that something this simple is so hard to do...

2023-03-13, 12:42:36
Reply #18

TomG

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Bear in mind Chaos "got involved" in 2017, that is 6 years ago now...... also you are assuming that this transparency issue ever worked any different, but there's nothing to say it was any better than it is now ;)
Tom Grimes | chaos-corona.com
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