Sections Anywhere has two types of image fields - image and image_picker:
image: saved to the asset folder of your theme
We no longer develop sections with this field type. The disadvantage is that image filters cannot be used when templating on images from your assets folder.
image_picker: uses images already uploaded to Shopify files (admin/settings/files)
This type of field is ideal for templating. However, you must upload the image separately as Shopify does not provide an API for files.