I just got this question in email, and thought I should answer it publically to help other people who might be wondering:
I used following commands to convert D:\>convert -adjoin scanImage_1.tif -adjoin scanImage_2.tif -adjoin scanImage_3.tif three.pdf This didn't work. And I use D:\ >convert -adjoin scanImage_1.tif -adjoin scanImage_2.tif -adjoin scanImage_3.tif three.tif And convert three.tif three.pdf Did not work. Then I use D:\ >convert three.tif three.pdf Did not work How do I create single pdf file?
As far as ImageMagick is concerned, a PDF file is simply a format capable of storing more than one image in a file. TIFF files are another example, as are animations. Therefore, to turn multiple TIFF files into a single PDF, you just need a command line like this:
convert scanImage_1.tif scanImage_2.tif scanImage_3.tif three.pdf
Too easy. Obligatory advertising: you can find out more about this in chapter three of my upcoming ImageMagick book, which is slated to be released around Christmas.