Photography also presented some positive effects on artists. They no longer had to have models stand still for extended periods of time. Instead, they could take a picture and paint from it later which eventually altered the way artists arranged their subjects on the canvas. They could also paint from a new perspective. It wouldn't be practical to try and paint from a hot air balloon, but it was easy to take a picture from one and then paint it.
The invention of the camera liberated artists of the responsibility of correctly documenting the events of their time period. They could paint whatever they wanted however they wanted because cameras would create perfect representations of people. Someone could easily blame impressionism on the invention of the camera because it forced artists to question the purpose of their profession.
I also think that the invention of the camera changed the way people perceive artists. Before the invention of the camera artists served a purpose: They were supposed to paint people the way they really are and document history. After the camera was invented people didn't really need artists. They didn't have to go to them for a portrait or a realistic representation of anything, so an artists role in society changed.