How do photographers change photo backgrounds?

My son goes to a preschool. Once in a while some photographers go there and take picture of the kids. Then they send parents the pictures with the kid in different backgrounds, like sitting in front of a pond, etc.



How do they do that?



I understand that they could cut the kid's image from the original photo and paste it on different backgrounds. But that would be a laborious job. Wouldn't it? I saw a friend did it once with Photoshop and it took him at least an hour. I can't imagine professional photographers spend that much time for every kid knowing many parents won't order the pictures.



Do they really do that this way? Do they use special software? Or hire some people to do it for them inexpensively?How do photographers change photo backgrounds?
They use a chromakey (sp?) background, usually blue or green, and then the computer can automatically crop them into new backgrounds very easily. It's the same thing that the weatherman does on TV.

To do this manually, as your friend did, is VERY time consuming. I couldn't imagine doing it for every kid in a school.How do photographers change photo backgrounds?
well some use what is called photoshop it is a comuter program that you can scan the picture then it will be in your computer you then can make the picture flawless change skin tones anything even backgrounds then print it back out on photo paper and it will be the same picture altered
They probably just have a blown up image (one large enough to fill the frame in the camera's view finder) and change it in and out depending on the background that was requested. For the regular old color backgrounds they have lights on the ground shining up onto a white background and they just change the colored gels in and out.
Its easy to do in photoshop even if the background is not a single colour.

1. open the background you want it to be

2. open the photo of the kid/subject

3. copy the kid/subject into the background photo as a new layer, close the original file you opened of the kid/subject.

4. using the eraser, right click in the image and make the diameter small and harness 0%

5. erase around the kid. it will reveal the background you want (its the layer under the kid photo)

6. keep erasing around the kid till it looks good and then make the diameter larger and erase everything else to reveal the rest of the desired background.



The time it takes will depend on how messy the subjects hair is. If its tied up in a pony tail it will be very easy and quick.



Like everything in photoshop, theres a million ways to do the one thing. This method is quick and easy. There are other ways to extract a subject from the background and give a truly professional look but take a lot of time to remember the process.



Here is an example. The background was just a 2 second job in photoshop as well but the method for replacing the background as mentioned above are exactly the same:



Before:

http://members.iinet.com.au/~tmorgan/IMG_8583sml.JPG



After:

http://members.iinet.com.au/~tmorgan/Art.jpg



My other work is here: www.trevormorganphotography.com