I'm using Tridion 2011 (with DD4T, feeding an MVC webapp).
It seems that MetaData fields for Multimedia Components (specified on the Metadata tab of my Images Schema in Tridion) are not populating the corresponding property on the DD4T "Component" object. e.g. LinkedComponentFields[0].MetadataFields is empty and Multimedia.AltText is null.
Specifically the field I'm after is the AltText. But as the entire MetadataFields collection is empty on the Component, it's obviously not pulling through any metadata properties. i have tried using TemplateBuilder to set parameters in the Component Template (I set "resolve width and height" to yes, and the MergeAction to Merge) - this did not help.
Any ideas?
It is possibly caused by the linklevel. By default, links are followed for one level from the page or component that you are publishing. You can increase this by adding a parameter to the template invocation, called linklevel. Try it with a value of 2 first, then increase until it works.