### ImageMagick version

7.1.1.3

### Operating system

MacOS

### Operating system, version and so on

Monterey

### Description

The result of adding a grayscale image to an RGB in the meta channel results in an image that shows the meta channel as if it was in the alpha channel.  Is this the way it should look? Does not seem correct to me. Is there a bug?

Input:

![lena](https://user-images.githubusercontent.com/13458218/224761070-41aeda93-b7c7-40ba-80f8-652ea2aeee8d.png)

![mandril3](https://user-images.githubusercontent.com/13458218/224761081-fdb9d083-5efd-4842-9da7-ba631e586091.jpg)


`magick lena.png \( mandril3.jpg -colorspace gray \) -channel-fx '| gray=>meta’ meta.tif
`

[meta.tif.zip](https://github.com/ImageMagick/ImageMagick/files/10959346/meta.tif.zip)


### Steps to Reproduce

see above

### Images

see above
image with meta channel created from using -channel-fx does not look correct
This is a GitHub Issue
repo:ImageMagick
owner:ImageMagick
Title : image with meta channel created from using -channel-fx does not look correct
Issue date:

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### ImageMagick version

7.1.1.3

### Operating system

MacOS

### Operating system, version and so on

Monterey

### Description

The result of adding a grayscale image to an RGB in the meta channel results in an image that shows the meta channel as if it was in the alpha channel.  Is this the way it should look? Does not seem correct to me. Is there a bug?

Input:

![lena](https://user-images.githubusercontent.com/13458218/224761070-41aeda93-b7c7-40ba-80f8-652ea2aeee8d.png)

![mandril3](https://user-images.githubusercontent.com/13458218/224761081-fdb9d083-5efd-4842-9da7-ba631e586091.jpg)


`magick lena.png \( mandril3.jpg -colorspace gray \) -channel-fx '| gray=>meta’ meta.tif
`

[meta.tif.zip](https://github.com/ImageMagick/ImageMagick/files/10959346/meta.tif.zip)


### Steps to Reproduce

see above

### Images

see above
--- end body ---
