Bring something really simple, like a Yashica T4. Point. And. Shoot. I can tell you from personal experience that focusing too much on photography while your wife is around, will quickly kill the joy - for her! Choose your time to photograph very very wisely. Include her in as many of the photographs as possible, if she doesn't mind. Really. It's your honeymoon, after all. A memory of your first adventure together as a married couple.