How take a picture and have the background dark?

I want to take pictures of myself and have the bachground be dark where you can't really tell what's in it. I'm using an iphone 4. Someone said to turn the lights off and only have a bit of light in the room then use flash. What are your ideas?

Use photoshop or take the photograph at night with background objects far away.

If you want professional pictures, go with a D-SLR…

Anyway, for the background to be dark, you just need to be in a dark room and have only one source of light that focuses mainly on you. You would also need to be some distance away from the background so that it doesn't show in the light's reach.

Go outside on a dark night. Stand where there's NOTHING behind you. Have someone shine a light on your face while they take your picture. Voila!

With an iPhone, go into a dark room and stand far away from any walls and use the flash.

Photographs with the subject in sharp focus and a background in a diffused blur give a pleasing, surreal look. A film or digital camera featuring manual focus and aperture controls can produce this blurred background effect. A shallow depth of field and selective focusing draws attention to your subject. A blurred background can soften any distracting details.

Keep the subject far away from the background. Increasing the subject-to-background distance helps throw the background out of focus.

Move the camera closer to the subject. As you focus on the subject, the background clutter will appear soft and blurred.

Set the lens aperture to a wide setting. A 50mm lens often has a maximum aperture of f/1.8. Try photographing with a range of wide apertures, such as f/1.8, f/2 and f/2.8. This wide aperture results in a shorter depth of field.

Focus on a specific part of the subject, such as a person's eyes or a flower's center. Focusing with the limited depth of field makes the subject stand out and the background recede.