I’ve been asked a couple times how to force ProPhoto to show full posts when people visit your archive or category pages. Right now, the default for ProPhoto is to show excerpts of the posts in the category and archive pages. So, when a user clicks on an archive month, this is what they see:

If you want to change this so that the full posts are seen, in your WP Admin area, you’ll need to go to your “Design” tab (”Presentation” in WP 2.3.3 and earlier) and select “Theme Editor.” Then choose the file called “Archive (archive.php)” to edit it. (NOTE: don’t get confused with the file called “Archive (archives.php)” - they are named almost exactly the same - you want the one that is not plural.) In that file, look for a line that says:
<?php the_excerpt(''.__('Read More <span class="meta-nav">»</span>', 'ProPhoto').'') ?>
Delete it and then paste in this line:
<?php the_content() ?>
Click “update file” to save your changes and then check your work.
You can also do this with your category pages as well. Just open up the file “Category Template (category.php)” and do the same edit.
A word of caution, however. The ProPhoto theme was built to display excerpts only on these pages for a reason. That reason is to avoid ‘duplicate content,’ which search engines don’t like, and which can get you a small penalty in Google and other search engines. Basically, the issue is, search engines don’t like it when websites have multiple pages with exactly the same content. That seems spammy to them, because a lot of spammy websites have hundreds of pages of duplicate, computer-generated content. When you leave your full posts open on your category and archive pages, you end up with a good deal of duplicate content, because your posts may be shown in full in 4 or more pages: your home page (or paged interior pages), your single post permalink page, your category page, and your archive page. This is why a lot of WordPress themes excerpt posts on archive and category pages. It is also why lots of blogs even excerpt posts on their home page.
Technically, the best search engine friendly way to do things is to have only your single-page permalink post page show the entire post, and have every other place show an excerpt. Now, that’s a little extreme, so ProPhoto was built to be a compromise between what’s good for your readers and what is good for the search engine robots. You’re more than welcome to change your archive and category pages to show the full post, just do it with the awareness that there is search engine optimization tradeoff. At the end of the day, most people’s blogs are for people and not search engine robots, so you may decide that ease-of-use for your readers is more important. I just thought you might like to know why the theme (and many themes) are built that way.