Create a list of my content type

Hi all

Having successfully created my own content type (AstroImage), I would like to create a simple 'gallery' showing a thumbnail of the body image of each node. The nodes would also be grouped into 'albums' by Taxonomy.

Now, I have been able to make a start for a single image using the following:

<?php

$query = new EntityFieldQuery();
$result=$query
  ->entityCondition('entity_type', 'node')
  ->entityCondition('bundle', 'basic_image')
  ->propertyCondition('title', 'Image2')
  ->execute();

$nid = current($result['node'])->nid;
$node=node_load($nid);
echo drupal_render(node_view($node));
?>

But this renders the whole node.

Example:
I have 20 AstroImage entities, 10 of which are tagged as 'NGC'.
When a visitor clicks on a link to show all 'NGC' images, they are taken to a new page which shows the 10 thumbnails. They then click on a thumbnail to be taken to the full node to view all the image details.

Can someone point me in the direction of a how-to to extract the image field from the nodes (field_astro_image) and output that?

Thanks in advance
Daz
Win7 64-bit
Drupal 7.19
WAMP 2.2
Apache 2.4.2
PHP 5.4.3
MySQL 5.5.4