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I uploaded my pictures using UploadSiteHostedPictures. I chose picture with the largest size that was returned in the response and used it in my AddItem request. However, when I go the view item page for the listed item, the image appears to be significantly smaller in the picture area (next to the title). What does this happen?
When you upload pictures to eBay using UploadSiteHostedPictures, you get back urls for multiple sizes for the image as below:
<!-- more PictureSetMember containers -->
When you use this in the AddItem request, you should use the url returned in the FullURL field. When you use this, the correct size is automatically rendered when users go to the view item page or when they click on the enlarge link.
Here is a sample snippet of the AddItem request:
<?xml version="1.0" encoding="utf-8"?>
<!-- other required fields need to be specified -->