I am trying to make a 3x3 montage with a hole in the middle. But the hole always appears to the right of center, i.e. at -gravity east rather than center. Note there also appears to be a slight gap between tiles 3 and 4, which is more obvious when using -background red.
Is this a bug or am I doing something wrong?. See http://www.imagemagick.org/Usage/montage/#null
Here is my test with 8 copies of rose: and 1 null: in the fourth position.
montage -tile 3x3 -background red -geometry +0+0 rose: rose: rose: rose: null: rose: rose: rose: rose: rose_montage.png
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