By Rephopy Mar 15, 2010 0 comments

A zoom lens is one where the photographer can vary the focal length within a predetermined range, whereas this can not be changed to "prime" or fixed focal length lens. The main advantage of the zoom lens is that it is easier to achieve a variety of composition or perspective (due to changes in the lens is not required). This advantage is often essential for a dynamic subject matter, such as in photo journalism and photography of children.

ZOOM LENS vs PRIME LENS

Keep in mind that using the zoom lens does not mean that no longer have to change their position; raise only increases flexibility. In the example below, the original position is shown along with the two alternatives using the zoom lens. If the main lens is used, then the change in composition would not have been possible without cutting the image (if desired strict composition). Similar to the example in the previous section, is achieved by minimizing the change in perspective and getting closer to the subject. Or, to achieve the effect of the opposite perspective, one could have enlarged and moved further from the subject.

By Rephopy Mar 14, 2010 0 comments

Understanding camera lenses can help add more creative control to digital photography. Choosing the right lens for the task can become a complex trade-offs between cost, size, weight, lens speed and image quality. This tutorial aims to improve understanding by providing an overview introduction to concepts related to image quality, focal length, perspective, prime vs. zoom lens and the aperture or f-number.



ELEMENTS & QUALITY IMAGES

All but the simplest cameras contain lenses which actually consists of several "lens elements." Each element of directing the path of light rays to create images as accurately as possible on a digital sensor. The goal is to minimize the aberrations, while still utilizing the elements of the least and most expensive.