app/views/pictures/_thumbs_list.html.erb
<ul class="pictures-thumbs">
<% object.pictures.find_all do |picture| %>
<li data-picture_id="<%= picture.id %>" title="<%= picture.description %>">
<a href="<%= url_for([object, picture]) %>" class="thumb"
data-components="modal" data-modal-options='{"remote":"true"}'>
<%= image_tag picture.image.thumb.url, class: 'thumb-image' %>
</a>
</li>
<% end %>
</ul>