this is the first time I’ve heard of the position of keywords matter in terms of SEO.
I think that the first 100 or so words have a higher importance, but don’t think that the actual placement matters.
SEO optimization for a photographer I would say requires a lot of off-site optimization. I mean, how many Photographer and given City are there already? So optimize the page title, keywords and description metas, and use a good descriptive alt tags for the images. I also like to suggest a blog that links to the portfolio. Blogs are like Google keyword fodder now-day.
Additionally, my little trick for image galleries is to host images with flickr. That way you already have strong tagged links pointing to your site. Though I must admin, I can’t substantiate this with any hard data, but it seems reasonable to me

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