The ISO should be in the file. Download Opanda IExif 2.3 available free at www.opanda.com and open a jpeg created in the camera with IExif 2.3. It should show the ISO. You can also check the image data in the camera. See page 116-121 in the D5000 Users Manual. If you modify the file in PSE7 and put it back on the card, the camera will not be able to see the image. Good Luck and Enjoy your Nikons!