Batch-convert images to TIFF (AppleScript, Mac OS X)

images to TIFF.scpt

# this script converts all PDFs and images selected in Finder
# to the TIFF format and appends .tif to the file name

set t to (time of (current date))
tell application "Finder" to set sel to selection
set errors to {}
tell application "Image Events"
	repeat with img_file in sel
		try
			set img_file to img_file as text
			set img to open img_file
			save img as TIFF in (img_file & ".tif")
			if (class of result) is not file then error "could not convert to TIFF"
			close img
		on error errMsg
			set errors to errors & ((name of (info for (img_file as alias)) & ": " & errMsg & "\n") as text)
			try
				close img
			end try
		end try
	end repeat
end tell

# error report
set errcount to length of errors
set msg to (((length of sel) - errcount) as text) & " files converted to TIFF in " & ¬
	(((time of (current date)) - t) as text) & " seconds.\n\n"
if errors is not {} then
	set msg to msg & errcount & " errors occurred: \n" & errors as text
end if
display dialog msg

The lines 24 to 31 will generate a report, see example output.