Thumbnails are great, but some folks post thumbnail code from Photobucket that does this:

Which is poo, since you prolly want to just see the full-sized pic, not have to load the page around the full-sized pic resized to 600 wide (if you're running Firefox and right-click the pic and go
View Image you can see it's the full pic). I think by default this code is inserted before the filename...
?action=view¤t=
To change it, click
account options at the top right of your Photobucket page:

And go down to
Album Settings and uncheck
Images Link Back To Album.

Then if you click
Link options, this window pops up:

If you don't know what those options mean, just select the ones I have. Which looks like this on your album page:

If you copy and paste the Direct Link in a post, it'll just show a link which takes you to the pic; IMG Code will embed the full-sized pic, and having changed your album settings as above, the thumbnail should now do this:

Win. Read on for yet more tips...
You don't have to go through all that Photobucket-related stuff just to post thumbnails, though... you just need to know the form of the thumbnail BBcode:
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[URL=address of full pic][IMG]address of thumbnail[/IMG][/URL]
The thumbnail is embedded with the IMG tag, which is nested inside the URL tag the same way you can replace a bare address with a word in a text
link:
Code: Select all
[URL=http://www.randomwebsite.com/]link[/URL]
So the code for the above thumbnail looks like this:
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[URL=http://i4.photobucket.com/albums/y111/Kimmo666/AppetiteforDestruction.jpg][IMG]http://i4.photobucket.com/albums/y111/Kimmo666/th_AppetiteforDestruction.jpg[/IMG][/URL]
Notice how the the thumbnail's filename has
th_ stuck on the start? Tinypic uses a similar trick...
The following kinda relies on you using Firefox, or knowing how to do the same stuff in your browser of choice. If you're using Internet Explorer, that's prolly not by choice and you should get Firefox cause this stuff is a hassle in IE, plus it generally sucks. If you're using Opera or something, you prolly know how to get a pic's address.
So anyway, in Firefox, if you right-click almost any pic you should see an option to
Copy Image Location. This is equivalent to Photobucket's Direct Link above. So if you can find a small copy of a pic you want to post, you can post a thumbnail (unfortunately this doesn't apply to the thumbnails Google Image Search makes, cause they're dynamically generated).
For example, say you want to link the pic of carbon nanotubes from Wiki's
Space elevator page. You can right-click the thumbnail to get its
address (mouseover the link to see it in your status bar), and paste it in your post. Highlight it and click the
Img button to make it an embedded pic, then go back to your Wiki tab and copy the main pic's
address (clicking on the thumbnail when you've copied its address so the main pic loads while you're pasting the thumbnail's address is a good move). Now go back and highlight the thumbnail address including IMG tags and hit the
URL button. Click after [URL and hit = and paste your main pic's address, and voila.
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[url=http://upload.wikimedia.org/wikipedia/commons/thumb/5/53/Types_of_Carbon_Nanotubes.png/646px-Types_of_Carbon_Nanotubes.png][img]http://upload.wikimedia.org/wikipedia/commons/thumb/5/53/Types_of_Carbon_Nanotubes.png/180px-Types_of_Carbon_Nanotubes.png[/img][/url]

It's a lot easier than it sounds in practice... especially if you know Ctrl-V means paste.
Remember the
th thing with Photobucket? Tinypic puts it on the end of the filename instead, eg the thumbnail for
http://i37.tinypic.com/2hyzz8o.jpg looks like
http://i37.tinypic.com/2hyzz8o_th.jpg . So you can grab the direct link for any Tinypic image, paste in some IMG tags and add the
_th, then add your URL tags and the main pic's address already in your clipboard (where things are copied to before pasting). The same technique can be used to reconstruct Photobucket's thumbnail code by sticking
th_ on the start of the filename.
And another thing... if you're using Firefox, which I highly recommend if you have a lot of RAM (it does have memory leaks and can use restarting every couple of hours on lower-end machines), I also highly recommend grabbing the
ImageTweak addon. It kicks arse; you can configure a bunch of stuff about how bare images are displayed like what colour the background is (grey or black is heaps better than white), and pics are centred and zoomable FTW.