1. well when you ask if i can trust a pictures you see in the media i think it depends on what you are talking about. for example if there is a woman looking for some sort of plastic surgery. on the internet and on T.V. there are before and after pictures so then maybe the after pic of some other woman cant be trusted because people will do anything to get publicity. so maybe this woman gets her surgery and she wonders why she looks so horrible but on tv it looks so good.
a second example where pics cantb e trusted is those loose weightcomercial with the weight loss pills. people in the comercials look all extra plastic when in actuality thats is not how it is.
a last example of hpw pics are unworth is the pics of models and how young ladies think that is is true beauty. some of these picture consist of people with no pores in their skin. we all have pores. this is all false advertisment and cant be trustd.
2. how to differenciate a credible picture from one that is not credible. it depends on what the photo is pertinent to. the given examples above are questionable. the weight loss pictures and plastic sergery pictions can and cant be deamed as credible. but the super model pictures are automatically known as not credible. not saying that these women and mean for that matter arent beautiful. make up works real miracles. it hides alot. as shown here: http://homepage.mac.com/gapodaca/digital/bikini/index.html. these are examples og what make up does. it decieves you. these pictures are not credible.
3. manipulating a photo isnt always bad. its ok when the picture is not bwin used to scam people like for advirtisment purposes. like cartoons or art work. artist have different visions some of which include manipulation to their art. an artist cant be faulted for a manipualted picture because it is the way they see it. an example of art that is manipulated is shown here: http://images.google.com/imgres?imgurl=http://www.rafelalmaary.com/images/manipulated-images/SunFlower.jpg&imgrefurl=http://www.rafelalmaary.com/manipulated-images.htm&h=404&w=595&sz=90&hl=en&start=3&tbnid=uc3lPBqiGYZc1M:&tbnh=92&tbnw=135&prev=/images%3Fq%3Dmanipulated%2Bpicture%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN
visual:
here its ok because ur your scaming anyone and because an artist has the right to be creative. its also beautiful.