I'm wondering what the native resolution of your images might be. If you are shooting digital with highly-compressed JPEG files, then pixelization is inherent, especially if you are using a point-and-shoot and it is set to maximize the number of images you can fit on the memory card. Check your camera's image quality setting and ensure that it is set for the highest quality JPEG file. Of course, if you are an advanced amateur photographer and you shoot RAW... disregard. In that case, I don't have an explanation as I do shoot RAW, post-process in Lightroom and PS5, and my images are high-resolution. My camera is the Nikon D300.