1. Introduce yourself with photo challenges. Attend to other blogger’s challenges or create one for your followers.
2. Develop a photo challenge into a voting area. Create a gallery and send the link to people who are interested in photography. Every week change your theme photo according to the viewers opinions/votes.
3. Crave yourself for feedback not only about technical issues, but also about how people feel when they look at the photo you’ve taken.
4. Use a portfolio theme instead of diary style blog theme. This will make your blog more acceptable for photography lovers, aka your audience.
These tips will both increase traffic and consistency of your commitment to your blog.
You can use my ideas freely. Also I recommend this for further reading about tips on serious blogging.