Tackling the topic of product detail page layouts is daunting because there is no short answer. Saying one element such as large product images increases conversion, though it’s proven, does not tell the full story.
The product detail page needs to be dealt with as a whole. The following article on Econsultancy does just that. It focuses on the ‘must have’ page elements, recommends where they should appear on the page, explains why, and provide tips on how to maximize the value of each.