Since files sizes can have a dramatic impact on your upload and processing times, we encourage you to optimize your file size to suit your needs prior to uploading your images. The maximum file size that can be uploaded is 32MB.
The chart below is a guideline for each indicated print size at a desired resolution.
Example: The recommended size for an 8” x 10” print at 300 ppi would be 7.2MB.
Keep in mind that this is for reference only and you should conduct your own print tests at various resolutions in order to establish thresholds for your workflow.
Read our blog post: High-Volume Photography Workflow: Why Image Size Matters