the technician and I finally figured it out. Since I hadn't been getting good printing copies using the photo ink, I thought the cradle that came in the box might be something I was supposed to be using. That turned out to be a "holder" for the cartridge when it is not being used.
Eventually, I was steered to a page which explained the correct combination of cartridges to use. 57 is the color cartridge, whether it be regular or photo. The other cartridge uses a 56 or 58. I had to make sure that I was using the 57 PHOTO and the 58 PHOTO GREY rather than just the black and white cartridge or the photo grey with just the color cartridge.
Still, I don't see that using the photo ink makes a much better photo print than using regular ink. Still, perhaps the photo inks last longer.