I wanted to post what eventually worked - a combination of several items put forward.

Creating the initial Photo image with no reference, then immediately loading the image from the file.

    # Start with a blank image - somehow this causes memory cleanup
    $TK{'image-'.$NVP{'Id'}}=$TK{'canvas-'.$NVP{'Id'}}->Photo(-file =>
+ "" );

    # Create an image object for the image file of the correct format
    $TK{'image-'.$NVP{'Id'}}=$TK{'canvas-'.$NVP{'Id'}}->Photo($NVP{'Id
+'},
                                                              -file   
+=> $NVP{'File'},
                                                              -format 
+=> $image{'extension'});
[download]

    # Create a "catch" for closing the window
    $TK{'pw-'.$NVP{'Id'}}->protocol('WM_DELETE_WINDOW' => [\&CleanUpOn
+Exit, $NVP{'Id'}]);
[download]

  sub CleanUpOnExit
  {
    # Get the id
    my $ID=shift(@_);

    # Delete images on the canvas
    $TK{'canvas-' . $ID}->delete("all");

    # Delete the original image
    (delete $TK{'image-' . $ID})->delete();

    # Destroy the popup window
    $TK{'pw-' . $ID}->destroy();

    # Exit the Tk window
    Tk::exit;
  }
[download]

So I wanted to say thanks.

nzsvz9 - formerly known as the mad memory monger of my own creation