Processing a folder of images with Applescript

Hi everyone

I am having a problem with my Applescript that I want to open a folder of images and process in PS.

The script works fine on a single test image whose file path I hard coded to open, but after adding the looping section, I'm not sure I have the right set up to open each image.

That part of my script is:

set sourceFolder to "Users:etc:etc" as alias

set destFolder to "/Users/etc:etc"

--source and destination folders for the images

tell application "Finder" to set imageSet to every file in sourceFolder

tell application "Adobe Photoshop CS6"

  activate

  set ruler units of settings to pixel units

  repeat with i from 1 to (count of imageSet)

  set currentImg to item i of imageSet

  open currentImg

  ....

  (rest of the code to adjust the images)

  ....

  end repeat

end tell

The error i get is "Finder got an error: document file "(filename)" of folder "(folder name)" (the rest of the file path) of startup disk doesn’t understand the “open” message." when it halts at the 'open currentImg' command

Just wondering if anyone could help me with this? Or offer some code that might work?

Would be appreciated, as this is the last thing I need to do to finish the script and get the job completed.

Thx in advance

Marty