Both technical and aesthetic aspects of digital photography are derived from conventional photography, and hence a good knowledge of photographic skills also help to make or break a picture. Inevitably, digital photography brings with it new techniques and means to capture an image. Basic photography skills such as lighting, exposure and composition are naturally important. For conventional cameras, the time lag from the moment your finger depresses the shutter release button till the moment the shutter opens is virtually negligible. On the other hand, for most digital cameras, there is a noticeable time lag which varies across the many camera models.
Response time is especially slow on the cheaper models.
For some makes, there are small beeps or clicks to let the user know when the picture has been taken. For others, the image taking process is so quiet that you may not even know if the camera has responded. You may think that this is an advantage over conventional SLRs with the noisy slap of the mirror, or the sound of the shutter of a rangefinder. Cheaper camera models come only with digital zoom, whilst the high-end ones come with both optical and digital zooms. Optical zooms work basically like your conventional zoom lens whereby lens elements in various groups are moved to change the focal length of the lens.