These things are just matters of politeness:
- If you share a picture that you found somewhere else online, tell your readers where you found it.
- If it's a professional shot and you know who the photographer and/or model is, tell your readers that, too.
- If you have only incomplete information about a picture you found, tell you readers as much as you know.
- If you publish a story on the EMCSA and someone else helped you with it in any capacity (even proofreading), thank them by name at the start of your story.
What it all boils down to is this: if you want credit for the things you do, then it only makes sense to give others credit for the things they do.
End of rant. I promise to give you something sexier next time around. ;)