Generally, if SEO takes too much of your time or you do not have the time to learn it on your own, it's time to consider hiring someone to do it for you. With that, comes an added expense which may or may not be affordable to you. It's a tough decision to make. There are quite a few qualified SEO's on this forum (KP, joshz, tstobler)
Photography is a hobby of mine and I tend to revisit sites where the content (articles, images, tips, etc.) are easy for someone at my knowledge level to comprehend, flows nicely and presents tips & tricks to expand my knowledge in an easy to read format. Camera settings are technical and it's easy to get lose or confused. You will have visitors with variable degrees of expertise and you will have to see where to focus your efforts.
If I were you, I would stick to what you know and focus on creating awesome content. It certainly cannot hurt you. Since you say your on-site optimization is ok, sift through the data and give your visitors what they want. Great content will eventually yield links which will help boost your rankings.
"Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime." Chinese Proverb