If the colors of your print look very dull or just plain inaccurate, you may have used the wrong color space. Check your camera menu right now. Does it say Adobe RGB? If so, you have just found the cause of the problem. Simply change it to sRGB in your camera menu and don't look back. The reason is simple; it gives the most consistent results. Not only does it work well for printing, but also for images shared on the web. Now there will be some experts who proclaim Adobe RGB to be superior as it technically captures more colors. While this is true in theory, it does not translate well in practice as most printers are set to sRGB. If you're not sure, ask the lab what color space they recommend. For even more on this topic, check here for starters.