It turned out to be quite simple.
Code: Select all
convert test_0001.png test1.pdf
"convert: UnableToOpenConfigureFile"
Adding the suffix to the command will sort that out
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convert test_0001.png PDF: test1.pdf
Code: Select all
convert test_000[1-3].png PDF: test.pdf
Optionally you can add commands like -rotate 90 or -resize 50% for further manipulation.