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C4D Alpha Channel - 10% of the image not showing up.

Message 1 of 7
1100 Views, 6 Replies

C4D Alpha Channel - 10% of the image not showing up.

Hey guys, I'm relatively new to C4D Arnold and loving the features. I'm currently having an odd issue with my Alpha Channel Texture in Arnold.

All works well, except for a select 10% or so. What I basically have is a PSD/PNG or TIFF bottle wrap (White Text and design) that goes over a solid color on my water bottle.

All works perfectly, except for the logo portion of the wrap. There is a gradient (the design is not 100%) opaque in photoshop, thus when it is applied in Arnold, it is not showing up as it should.

All areas of the wrap that are 100% opaque in Illustrator/Photoshop show up perfectly, while this small section does not. It is the only thing I can think of, as it is the only thing that separates it from the rest of the design.

What could I be doing wrong? Is there a setting that is not able to pick up the entirety of this subtle portion of the design? I'd like to also mention that on *some* of the wraps (there are a few), the darkest portion of this section *do* show through, if ever so slightly.

Nevertheless, the subtle details of this logo do not show up on the vast majority of the project, and there is very little that I can think of to solve it.


Labels (4)
Message 2 of 7

How do you blend the logo and the surface shader? Do you use the alpha channel of the image to control the mix?

Message 3 of 7
in reply to: tylerJBBG5

@Peter Horvath I have one label and tried using both an alpha image in the shader network that serves as the alpha channel for the entire thing, as well as just putting the image into the "alpha" texture... yielding the same result both times... do you think I need to separate the logo and rest of the wrap from each other? Even still, I'm not quite proficient enough (I don't think) to know where to go from there...screen-shot-2018-04-10-at-121817-pm.png

Perhaps I'm doing the shader network nodes incorrectly?

I modeled this texture setup after a few tutorials I saw.. as well as it being similar to the result ofthe "make this an Arnold texture" button as well... so hopefully it isn't too far off...


Message 4 of 7

I'm not sure, but I think what you need is to mix the logo and the base surface by the alpha channel of the image, something like this:


There was a similar thread recently, maybe this helps as well:

If that does not solve your issue, feel free to send me the scene and I'll take a look.

Message 5 of 7
in reply to: tylerJBBG5

I will check it out today and give it a go! If not.. definitely! Thank you so much man! 🙂


Message 6 of 7
in reply to: tylerJBBG5


So after some good attempts.. I am closer. Your setup was a winner when combined with the JPG version/image loaded into the alpha channel setup.

However, the finer details are still eluding me. I start to see some of them (attached, you can make out some of the dots), but I still need it to be a tad more visible.

I set up a folder with the JPG wrap, Alpha, PNG Wrap both normal and "contrasted". The contrasted PNG is still showing up.. so it seems like there is an issue with the shader not picking up the extremely subtle areas of the wrap.

I gave some of the tips on the other thread a shot.. but the only thing that made a change was this response here! So.. thanks!! I'm closer.

I'll send you the folder and if you *do* get a chance... maybe theres something in the settings that you'll see that I am doing wrong.

Either way, thanks again for the help! There *is* improvement and thats always good.


Message 7 of 7

Just send the files to Thanks.

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