i find that the digital zoom on 4mega pixel dc looks quite good but not on my 2 mp camera...mine appear to me very grainy when i use digital zoom....but if i just use optical zoom the quality is quite good.......
hmm when u use digital zoom the dc is actually trying to use ur bigggest image and try to enlarge it. So for a 4mp cam u have more image info for the cam to enlarge unlike a 2 mp cam.
Try this in PS it will be easier to understand. Use a small image and resize it bigger, u will find the image quite bad look cause the computer is trying to think how to fill in the missing pixels but there is no image imformation avaliable. SO it tries to guess base on the surrounding pixels.
I feel digital zoom is not a good idea, at least for 2m pix camera. The picture quality is very bad, and if you really want to do this, you can enlarge it once downloaded into computer. donno why they build in this function into the camera, now when i use my canon ixus, i must be very careful to avoid digital zoom.
i know it bad but i didn't know it was that bad...i was shooting some animals at the zoo but 3x optical zoom is not enough for some animals.....like the white tiger so far.....so i used digital zoom...and the result was....blur blur blur.