Incorrect glass alpha Tweet

[Scrudje]

Whats wrong with reflections/refractions in the png? they do not correspond the original jpg preview

[paride4331]

Hi Scrudje,
I think you forgot to select Reflection pass.
you should assign Active layer ID as you want and select render pass.
Eventually you could check Keep environment option in Kernel panel, saving image with alpha.
Regards
Paride

[Scrudje]

Hi Scrudje,
I think you forgot to select Reflection pass.
you should assign Active layer ID as you want and select render pass.
Eventually you could check Keep environment option in Kernel panel, saving image with alpha.
Regards
Paride

1. Doesn't matter reflection and refraction passes doesn't have this "black" strips like on original preview when alpha channel+render layer is on
2. If i check keep environment i ..... just look at the attach file.

Thank you

[paride4331]

Hi Scrudje,
maybe I don't understand the question, maybe you're not considering that you are working with linear compositing. therefore black equals 0.
viewtopic.php?f=27&t=66757&p=336128&hilit=photoshop#p336128
Regards
Paride

[Scrudje]

Bug is present and so far it is not solved. Today only solution of this problem is "Compose":

1. Render of the image with the included alpha channel render layer(optional)
2. Render of the image with the switched-off alpha channel.
3. Compose this 2 images with aplha mask of the image with the included alpha channel + manual brush mask on problem areas

render 2 times the image that on a result to receive 1..... no comments. Octane for enthusiasts/masochists

[paride4331]

Hi Scrudje,
layers allow users to separate their scene geometry into parts, where one part is meant to be visible and the rest of the parts “capture” the side effects of the visible geometry on it. The layers allow different objects to be rendered into separate images where in turn some normal render passes may be applied.
The Render layers are meant for compositing and NOT to hide parts of the scene itself.
you can use "Render Layer Mask" or criptomatte now as an alternative to this option.
As for the shadows, you can use the diffuse material "Shadow Catcher" and for the reflections you can use only "reflection pass".
Regards
Paride

[ramone163]

Hi Scrudje,
layers allow users to separate their scene geometry into parts, where one part is meant to be visible and the rest of the parts “capture” the side effects of the visible geometry on it. The layers allow different objects to be rendered into separate images where in turn some normal render passes may be applied.
The Render layers are meant for compositing and NOT to hide parts of the scene itself.
you can use "Render Layer Mask" or criptomatte now as an alternative to this option.
As for the shadows, you can use the diffuse material "Shadow Catcher" and for the reflections you can use only "reflection pass".
Regards
Paride

Paride, forget about passes. I think the problem is, that with Affect Alpha ON we lose some specular-reflection information. Check my images.

[Scrudje]

Paride, forget about passes. I think the problem is, that with Affect Alpha ON we lose some specular-reflection information. Check my images.

You absolutely right, this is the problem about i post.

[Scrudje]

Hi Scrudje,
layers allow users to separate their scene geometry into parts, where one part is meant to be visible and the rest of the parts “capture” the side effects of the visible geometry on it. The layers allow different objects to be rendered into separate images where in turn some normal render passes may be applied.
The Render layers are meant for compositing and NOT to hide parts of the scene itself.
you can use "Render Layer Mask" or criptomatte now as an alternative to this option.
As for the shadows, you can use the diffuse material "Shadow Catcher" and for the reflections you can use only "reflection pass".
Regards
Paride

Hello Paride4331!

Does not matter how i make final image: render 1 beauty pass or render compositing passes like diffuse/reflect/refract etc. Final image must be with alpha which is included all reflections and refractions from beauty pass. In my example alpha does not have all this details(black strips from cylinder), alpha just make this black strips transparent, but it should not be.

If i open exr/tif/psd etc. in soft like photoshop i can blend passes/make alpha masks and change to any background, but i need PNG with plausible alpha without any blends.

I hope well explained

[paride4331]

Hi Scrudje,
I see, yes I suppose something goes wrong, I will ask to developers.
Meanwhile a workaround is creating an environment to use in Octane DayLight refractions/reflecliotions.
Regards
Paride