To answer the copyright queries, you should be concerned & watchful as to what you copy & from where.
Each country has its own laws governing copyright & usually on forums the laws that pertain to this would be those of the country/state that the site owners are based.
Broadly speaking, if you take away possible income from the source (eg post a pic that others are paying to reproduce) then you can certainly be in trouble. Always take the time to check for copyright links or the copyright symbol. Definitely pics etc with watermarks across them are copyrighted & seeing as the owner took the time to put these on, I wouldn't be copying them at all.
I often post pics & add a link if it from a site with a story attached. This won't cover me for being sued if the site owner objects at all & so I am choosy and don't over do it. Often it gives the site more traffic which is money in their pockets anyway.
As for pics that have been made on tumblr sites, facebook, etc (fan made pics mainly) it's a grey area. Where did they get the original pics from? Perhaps they photoshopped a copyrighted image?
Some private users get very irate if you take their work & post it without a link acknowledging the source. Some don't like you copying their work at all. The worst thing people can do is to copy something froma site who have taken time to put their 'name' across the top/bottom or somewhere on the page/pic & you take it & cut that reference off; very bad manners & you will be caught out as 'everyone' sees 'everything' posted eventually.
Many people take pride in their 'art' & take a lot of time doing it, it's one of their 'babies' so be very aware of what you 'take'.
Use common sense, ask the owner if you are not sure & be ready to defend yourself if you do it often.
*This is not professional advice, is certainly nowhere near exhaustive & each user should investigate the laws pertaining to copyright for themselves to become more responsible users of the internet.
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Sherlock Holmes 28 March 13:08
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