Yeahhh, there are a ton of screencaps here. Thought a list would make it easier to find what you're looking for.

In the episodes where Ben is shown in flashback form (as Sterling Beaumon), I've included a link to the side if you're looking for just caps of young Ben. Emerson's Ben will be further back in the gallery if you just click the episode title, but you can filter the keywords by his name once you're there if you just want those.

Season 2
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Season 3
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Season 4
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Season 5
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Season 6
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Epilogue
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As of January 2011, all of the episodes & epilogue have been capped and uploaded. That's all, folks!
(Unless someone wants to go through and look for Ben in any deleted scenes...)