i notice alot of the pictures people shoot are at f2 or f4, which causes the background to be slightly blur( they also mentioned its auto)

in order to get a clear sharp overall picture, need to capture at f8 rite??? but how come auto camera tends to go around f2 or f4?? anyone can enliughten me???

Probably the focus object has been given priority, and therefore the camera assumes that a foreground object is designated as the main subject, adjusts the aperture (f number), ISO sensitivity, shutter speed to capture that object.

If you want to have background focused sharply, you can try changing the scene mode / landscape mode on your camera. Alternatively, aim your focus box to the far background so that the camera is try to focus on it, adjusting the capture settings accordingly.

but by aiming behind, will the foreground be blurred???

Yes, there is a chance the foreground might be blurred, unless you choose the smallest aperture opening (big 'f' number) like 8.0. With a large 'f' number, you are likely to get under-exposed shots, unless you use slower shutter speeds / high ISO.

Best is to experiment a bit with your digital camera. Try progressing to semi-advanced / manual mode and see if you can get the perfect settings.

sunbeam, like your pumpkin la? it looks underexpose to me....but i think u shiould be at f2 or something rite??

It's kinda futile to ask that question actually, since unless it's documented, only the camera's programmers can tell you why those choices were made. Not to mention that every camera model is different.

I can get a blur background at F8 - F11 also, it's not only the aperture that counts. If I wanna get an overall sharp image, it's not only aperture as well.

Another thing, I dun understand WHY you need to start a new topic for a new questions

That shot was slightly underexposed, but I was playing around with some camera effects (colour ascent on yellow), which is why the background appears dull and gray scale.

You get a blurrer background if:

1) You use a longer focal length e.g. 300mm
2) You use a brighter aperture e.g. F1.4
3) You focus nearer e.g. 45cm away

On a digital camera (not a digital SLR) F2.8 looks like F11 on a digital SLR. Why?

Because the real focal length of a 3x zoom digital camera is about 6-18mm. Its crop factor is 6x whereas a digital SLR's crop factor is 1.5x. Therefore, while a digital camera seems to have 36-104mm focal length, it has a bigger depth of field because of the wide focal length.

To get a bit more depth of field with a bright aperture, use hyperfocal focusing. This means to focus 1/3rds of the way into the subject. For example:

Supposing 1, 2, 3 and 4 are objects all the same distance from each other.

Your camera ----------------> 1 2 3 4 ---------------> background

Point at #2. #1 and #4 will be equally in focus. Hence, when focusing on a face, focus on the eyes and the nose and ears should be reasonably in focus. Darken the aperture if you find it's not in focus enough.