B&N Online Coupon: $5 off for every $50 you spend (eg $10 off $100, $15 off $150, $20 off $200, etc)

If you like to buy camera and photography books (or any other books and items) from the Barnes and Noble website, coupon code BOOKSMART gets you $5 off for every $50 you spend. So the more you spend, the more you save. IF you buy $100 in books, you get two $5 off (= $10 off) discounts. If you buy $200 in books, you get four $5 off (= $20 off) discounts. And so forth up to $500. Exclusions apply. Coupon expires 5/28/17 at 3am ET.

Strategically this is good for items that have the same prices everywhere you look, or are rarely discounted. The Clearance section is another place to look for deals. You can drill down the sub-categories or go directly to the Photography Clearance section.