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I must be missing something here. I'm doing an extremely simple Import Image as Plane using the AddOn and the imported image has an alpha background but it renders (and even previews in the material preview) as black where the alpha background should be.

When I import, I select Emission & Transparent so the material setup is automatic. I've read similar issues but people are typically missing the transparent node and connecting the Alpha channel from the image into the Mix Node factor. But this is all here.

I must be missing something really stupid but I've wasted so much time trying to fix this thing. Any help would be greatly appreciated.

Not sure if it matters but I'm using 2.74 RC2.

Many thanks!

I created this dummy blend file to test outside my project but problem still exists. Here is the simple .blend file: AlphaTest

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The reason you see black in the background of your image is because your image is not using the alpha channel.

Press N to open the panel on the image/UV editor and enable the Use Alpha option for the image:

enter image description here

Other things could that could be happening:

1.-The Alpha channel was not enabled during the import process.

If you are using the images as planes addon to import images that have an alpha channel you have to enable the Use Alpha option, and then choose the shader you need.

In 2.8 check the box for Use Alpha

enter image description here

enter image description here

For older versions of blender the options are:

enter image description here

In newer versions of blender the Use Alpha box might not be there but you can still select to have transparency as you import the image:

enter image description here

2.-Your Image has no alpha channel.

Open your file in an image editing software (gimp, photoshop, etc), delete the black background to make it transparent and save it again in a format that supports an alpha channel (JPG files do not support alpha, PNG, TIFF, OpenEXR do).

enter image description here

How can you tell if your image has an alpha channel?

At the bottom of the UV/Image editor's window you can select which channels to display:

enter image description here

Switching from RGBA to Alpha will allow you to see the alpha channel only

enter image description here

The white areas on the alpha will be opaque, the black areas will become transparent.

Just for comparison here's what the same image with no alpha channel looks like (As you can see it does not contain the outline of the leaf, just solid white):

enter image description here

AS AN ALTERNATIVE

If you don't want to edit your image, you can use the black information to control the transparency using a node setup like this where the parts of the image that are darker than 0.1 will be used as the mix factor for transparency. (Note that I inverted the order for the mix shader sockets) :

enter image description here

NOTE Alpha transparency for the texture will only be displayed in rendered and material view.

enter image description here

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    $\begingroup$ cegaton, your response is unbelievably thorough. I really appreciate you putting so much energy into this. You are absolutely right that the image didn't have the alpha channel. I just did some testing with the exact same image in 2.73 and it works just fine. It appears that 2.74RC2 loses the alpha on the image when using Import Image as Plane. Now I have to figure out how to report this bug. I wouldn't have figured this out if you hadn't confirmed the image in the blend file had lost the alpha. Thank you very much! $\endgroup$ – Dale Forbes Mar 25 '15 at 13:06
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    $\begingroup$ I just confirmed that this is a known bug in 2.74RC2 and will be corrected in the final 2.74 release. Thanks again to cegaton. Either way, I just learned how to deal with these kinds of problems. $\endgroup$ – Dale Forbes Mar 25 '15 at 13:14
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    $\begingroup$ Thanks for priceless tip! $\endgroup$ – Rita Geraghty May 20 at 19:11

protected by David Jul 31 '17 at 19:41

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