copyright question

if you download a pic on the web and then you edit it, can you treat it as your own?

No.

I am pretty sure you have to design the whole image or have it be your image from the "Get Go"

there may be exceptions as to how you change it, my art teacher was talking about something similar a while ago.

wow. so that's a no, maybe, and could be. boy. anyway, thanks guys

If you edit it in such a manor you can not derrive the original from it you shouldn't get any problems.
Copyright is for the whole image maybe i am wrong but if you pick a certain part of the image that is not very distinctive you could use it to make it fit as a whole with other parts of your making or from someone else again.

A litlle bit from him and her and him and her overthere and you have a complete image and it's your own

Unless the copyright owner specifically places the image into the "public domain" or gives you permission to do so, you are NOT free to edit the image, whether it is to be used in a derivative work or not.

Using some small portion of an article or using a single image from a collection for use in a review IS legally allowed and does NOT require permission since it falls under the heading of "fair use"...but there is a big difference between fair use and a derivative piece of work.