I've taken this picture by accident. I have heard from my friend that was caused because of ISO, aperture and shutter speed configuration. I am not that expert with these 3 settings because I normally use the automatic configuration. Could anyone give me some tips on how to take another photo like this one. Thank you.
By the way, I am only using a GEX500 camera.
The shallow depth of field you see is a combination of aperture, sensor-size and focal-length.
This has nothing to do with ISO or shutter-speed but these have to balance the exposure.
The wider the aperture, the shallower the depth-of-field. The longer the focal-length, the shallower the depth-of-field. To maximize the effect you therefore should shoot as zoomed in as your can and with the widest aperture possible.
The key factor here is subject distance.
Aperture and focal length play a part, but nowhere near as much as subject distance. Your photo is a very good example of this effect. Due to the small sensor and short focal length in your camera you will have difficulty getting a blurred background in most circumstances. If you were to upgrade to a DSLR then you could use longer focal lengths (for the same field of view) which would help you get blurred backgrounds. If you were then to upgrade the kit lens to a prime (going from f/5.6 to f/1.8) that would help you blur backgrounds more, but still not in every circumstance. Or you could keep your current camera, not spend another dollar and just get close to your subject for nice blurred backgrounds every time.
In fact once you get really close then there's no way to avoid getting a blurred background, whatever camera/settings/lens you use, a fact which is the bane of macro photographers!
There are two ways of blurring the background or to separate the background from your subject.
1) Use shallow DOF by using higher focal length , keeping the subject closer to you than the distance between the background and the subject.
2) Use the "panning" technique to keep your subject static while displaying motion blur of the background....
these two can be used effectively to blur out the background from Your subject
Your question is relative to a concept named Depth of Field (DOF) which is impacted in sensor-size, aperture and focal-length.
The concept that your friend told you is "Exposure Triangle", which help you to control brightness of your pictures.
You can refer more in http://en.wikipedia.org/wiki/Depth_of_field
