Image Renditions are a great feature of SharePoint 2013. While writing another blog post about Image Renditions I figured out that there is actually a maximum size when adding an Image Rendition.
If you are used to add Image Renditions by using the UI you may have noticed the validation message “The value entered is invalid. Value must be a number between 1 and 2048” :
If you are a developer like me who is playing with the API before the OOB features this limit is not so obvious. When you are provisioning Image Renditions thanks to a SharePoint Feature you won’t have any messages or log entries to warn you. The Image Renditions with a width or height over 2048 will be simply ignored.
Is it possible to configure your environment to increase this value? No. When decompiling the IsValid method of the Microsoft.SharePoint.Publishing.ImageRendition class you can notice that 2048 is actually a constant.
It’s not really an issue in my opinion. You probably won’t need to generate renditions over this size but I think it’s good to know this limitation when deploying this kind of artifacts for SharePoint.