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i'd like to render a piece of paper, with a layer of transparent, glased ink. (see images below)

The thing is, i can't tune down the "alpha" settings in the Materials pannel, as it is already used by the "Images as planes" thing. Every time i try to change something in the Materials pannel, it goes wild because of the transparency of the png image. I am using cycles.

I'm a beginner in Blender and would love to see how you guys would do it. Thanks a lot!

enter image description here enter image description here


Here is an image to clarify :) enter image description here

Here is the file:

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  • $\begingroup$ So you have imported a png image with transparency and now want to make the visible parts of it a little translucent as well? Is that the problem? $\endgroup$ – Ectras Aug 24 at 17:07
  • $\begingroup$ yes ! It's exactly what i want to do. Making the PNG image a little transparent. :) Do you happen to know how i could proceed? $\endgroup$ – xyglon Aug 25 at 9:05
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If you have a look at the Alpha channel (plug the Alpha output from the image into the Surface Node from the Material Output), you can see that alpha is stored as a black & white image.

White means fully opaque, black stands for fully transparent parts. But values in between are also possible! viewing the alpha channel

So if you want the opaque parts to be partially transparent, you need to dim the white color to a grayish color. There are many ways to do this. For instance, mix the alpha channel with black color using a MixRGB node. If the factor is 0, the result will be the original image whereas a factor of 1 results in a completely black image (which means fully transparent). dimming the alpha channel

Now that we have seen the effect this has, we can connect the mix output to the alpha input of the Principled BSDF. Then connect the BSDF output back to the material output. And there is the transparent image :) partially transparent image

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  • $\begingroup$ Hi ! First of all, thank you so much for taking the time to guide me through this ! I followed the steps, my shading pannel is exactly like in your last picture, but my PNG image is still opaque. Do you know what i could do ? Thanks a lot :) $\endgroup$ – xyglon Sep 1 at 0:13
  • $\begingroup$ Hm, that is strange. Maybe you could upload your blend file to https://blend-exchange.giantcowfilms.com/ and share the link in your question? When you upload, you should make sure to do File > External Data > Pack All Into .blend in Blender first $\endgroup$ – Ectras Sep 1 at 9:39
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    $\begingroup$ I just uploaded the file. :) $\endgroup$ – xyglon Sep 2 at 8:25
  • $\begingroup$ Looking at your file, it seems that you forgot to set the Color2 of the Mix Node to black color. Does this solve your problem? $\endgroup$ – Ectras Sep 3 at 13:58

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