<p>I solved my own problem after some more trial and error. For awhile it looked like the fact that I was using Mental Ray shaders combined with general shaders was the problem, but that didn't really make sense so I kept tweaking. It turns out that an image plane I had tied to my camera was the problem. The image on the plane never rendered out, so I assumed the plane wasn't affecting the rendering, but it turns out it was showing up as a black plane when rendered. I deleted the plane for my render and it works fine now.</p>

CC BY-SA 3.0
2015-07-02T20:06:29.927Z
2015-07-02T20:06:29.927Z
KC McLaughlin
<p>I'm trying to export a scene to composite in Nuke.  When I "render current frame" and save the image from there, I get an image with an alpha channel, but when I batch render the images don't have the alpha channel.</p>

<p><img src="https://i.sstatic.net/myJnQ.png" alt="enter image description here"></p>

<p><img src="https://i.sstatic.net/qAubM.png" alt="enter image description here"></p>

CC BY-SA 3.0
2015-07-02T10:33:56.107Z
Hard to say. In general your _beauty pass_ should contain the alpha. Bmp is very limited, try to render as exr. Also check if _Pass Custom Alpha Channel checkbox_ is enabled.
p2or
<animation-rendering><nuke><compositing><maya><alpha>
Maya batch render missing alpha channel
KC McLaughlin
# Maya batch render missing alpha channel

(Asked by: username_0 on 2015-07-02)

I'm trying to export a scene to composite in Nuke. When I "render current frame" and save the image from there, I get an image with an alpha channel, but when I batch render the images don't have the alpha channel.

![enter image description here](https://i.sstatic.net/myJnQ.png)

![enter image description here](https://i.sstatic.net/qAubM.png)

**Tags:** animation-rendering, nuke, compositing, maya, alpha

> **Comments:**
> **username_1**: Hard to say. In general your _beauty pass_ should contain the alpha. Bmp is very limited, try to render as exr. Also check if _Pass Custom Alpha Channel checkbox_ is enabled.  

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## 1 answers

### Answer by username_0 on 2015-07-02. Score: 1

I solved my own problem after some more trial and error. For awhile it looked like the fact that I was using Mental Ray shaders combined with general shaders was the problem, but that didn't really make sense so I kept tweaking. It turns out that an image plane I had tied to my camera was the problem. The image on the plane never rendered out, so I assumed the plane wasn't affecting the rendering, but it turns out it was showing up as a black plane when rendered. I deleted the plane for my render and it works fine now.


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