By default, iTunes optimizes your images before it syncs to the device. This optimization results in a copy of the image that is of less quality than the original. This can be detrimental if you use your iPod to transport digital photos and other images to another computer. To bypass this process and keep the quality and resolution of your image, do the following:
1. Connect iPod to your computer.
2. Select the iPod in the iTunes Source list (Your iPod needs to be set to act as a portable hard drive).
3. Select the Photos tab in iTunes.
4. Check the Include full-resolution photos checkbox.