For my research for Squarespace template and also for future reference for my website portfolio as my work is getting more vibrant I researched website porfolios of photographers that decided for the front page grid and white background similarly to me and I compare them together.
First grid portfolio is by Ronald Stoops – http://www.ronaldstoops.com
Another one very handy with menus is Nicolas Fleure portfolio http://nicolasfleure.com/
Then Grid on the single pages at the portfolio of Frank Sauvaire http://francksauvaire.com/
And another grid by Marcus Erricson.
And I also checked some grids / digital magazine template provided for WordPress
Very important think about msot of those themes is the screen. When I’m opening the portfolio on my macbook air laptop is much less spacefull than on the big Mac room screen.