When will I see a filmstrip of photos in a message?
This article explains when a customer will see a filmstrip of photos in an email.
You will see a filmstrip of photos when an email contains attached photos or links to photos hosted at Flickr or Google Picasa. For attached images, certain images are filtered out if they are not big enough.
For Picasa Web Albums, we do not support links to single images. If an email contains attachments and/or multiple links you will see one filmstrip per set of attachments and each link.