Display excerpt for certain category, display 200 characters for rest

First & foremost here is my existing code. I am showing 6 posts on the homepage with the first 200 characters of the post displaying, followed by a ‘Read More’ button. This is great for my posts with words, but not so good for my posts with video. My solution is to have category 14 for all videos, when a category 14 post is to be displayed I would like it display the excerpt rather than the 200 characters.

?php query_posts('showposts=6');
if(have_posts()) : while(have_posts()) : the_post(); ?>

	<!-- begin post -->
	<div class="post">
		<h2> <a href="<?php the_permalink(); ?>"><?php the_title(); ?> </a></h2>
		<p class="date"><?php the_author_posts_link(); ?> on <?php the_time('m j, Y') ?> | <?php comments_popup_link('No Comments', '1 Comment', '% Comments'); ?></p>
		<div class="thumb"><a href="<?php the_permalink(); ?>"><?php dp_attachment_image($post->ID, 'high', 'alt="' . $post->post_title . '"'); ?></a></div>
		<p><?php echo dp_clean($post->post_content, 200); ?></p>
		<a class="readmore" href="<?php the_permalink(); ?>">Read More</a>
	</div>
	<!-- end post -->

	<?php endwhile; endif; ?>

My attempt to solve my code was this:

<?php query_posts('showposts=6');
if(have_posts()) : while(have_posts()) : the_post(); ?>

	<!-- begin post -->
	<div class="post">
		<h2> <a href="<?php the_permalink(); ?>"><?php the_title(); ?> </a></h2>
		<p class="date"><?php the_author_posts_link(); ?> on <?php the_time('m j, Y') ?> | <?php comments_popup_link('No Comments', '1 Comment', '% Comments'); ?></p>
		<div class="thumb"><a href="<?php the_permalink(); ?>"><?php dp_attachment_image($post->ID, 'high', 'alt="' . $post->post_title . '"'); ?></a></div>
		<p><?php if ( is_category('14')) {
				the_excerpt();
			} else {
				echo dp_clean($post->post_content, 200);
			} ?></p>
		<a class="readmore" href="<?php the_permalink(); ?>">Read More</a>
	</div>
	<!-- end post -->

	<?php endwhile; endif; ?>

This didn’t do it, but I think I’m missing something simple with my IF statement. Anyone have some ideas?