web design question about image display

Back in ancient times (okay, three years ago or so) I used to have my website setup in a way so that images like sketches or fanart and such displayed in a new pop up browser window, because personally when navigating thumbnails that just open an image, not a real page, I like not to go away from the gallery page. However I then did a a poll on this topic, and the vast majority preferred thumbnails to open the image in the same window. So I changed my site to match that preference.

However now I just found a neat javascript thing, Lightbox JS, that displays images in an overlay on the same page. If you surf with javascript turned off it'll behave just like before, so it doesn't break the basic navigation or anything like that, it's just an extra. And I'm considering to switch my site's picture galleries to this. To show the effect I created a copy of my fanart page using the script, so that you can see the effect. Just click on a link to a piece of fanart, and if you have javascript enabled, it ought to show the image in an overlay with the page underneath darkened (and please tell me if it doesn't work for you for some reason, or if there are any display problems, like distortions or whatever).

So given this alternative to the images simply opening in the same window, and having to use the back button, which do you like better?

[Poll #1133237]

ETA: Just to clarify, this script does not prevent you from opening the image in a tab with a different click (at least that still works for me, it was the first thing I tried), nor does it hinder saving images or any of the other annoying things some image display gadgets will do.

fanart (still a WIP), a freshly hatched Iskierka

Fandom: Temeraire Series by Naomi Novik
Characters/Pairings: Iskierka
Media used: only pencil so far
Rating/warnings: G, none
Notes/comments: I seem to be on a dragon kick lately. But I like Iskierka. I hope she looks enough like a baby while still fitting the description that they look just like smaller versions of the big ones. But making the head long and lean like I normally do for dragons to make them look ferocious didn't work for me for a baby dragon. The hatching pose took a ridiculous amount of time to get right. Maybe I'll do a real process post once it is inked and colored, showing excerpts from all the steps that were like tooth pulling, like the dozen thumbnails and head design sketches, and failed attempts. OTOH that would be kind of embarrassing, now it looks like I sat down and just did a pencil drawing as a process step...
Preview:

( the pencils are behind the cut )