Large Product images are key to showing off the very thing you are trying to get your customer to purchase.
What? High quality images of your product.
Why? A picture is worth a 1000 words. The better quality that picture is of your product, the more it will speak to your customers. A poor generic image of a product will result in little to no conversions.
How can I create larger product images?
Improve Clarity with larger product images on your category pages and product pages. In ecommerce, images are everything. They are arguably one of your stores biggest assets or should be.
If you have images that are high quality but appear small on your store, it could be the theme or a setting within the theme that is reducing the size/quality. Look at the product page settings for your theme to see if there are options for larger product and gallery images.
If you are using stock imagery and its below par, you need to get it improved. It may sound like hassle but getting a photographer in for the day to blitz through your catalog and get those images in high quality jpgs is a gold mine. There are also services where you can send off your products to get high quality images.
On a side note, lifestyle imagery is just as important. Finding influencers to create stunning imagery that you can reproduce on your site is a great way of improving your store visually.