Not every picture is the same and each picture is made different by the type of picture it is, that is full length, portrait and so on. To be able to take good portrait pictures there is a certain type of lens that you have to use to get the image right. In the paragraphs that follow I will talk about some points to consider when shooting a portrait picture.
In choosing a lens for a portrait you must take into account the prevailing conditions of the environment that you want to take the photo in. Light, wind etc. It is also important to consider the focal length. Why this is a consideration is because it is dependant upon the film size. From personal observation I have noticed that a portrait with 35mm film camera is best taken with a 105m lens and an 80mm requires a 160mm lens. You can see then how the size of the film has an effect on the lens that you choose and the eventual picture that you take.
If you are unsure as to how to make these adjustments in focal length, size of lens and film you can always ask around from fellow photographers who understand the concept better . Sometimes having a practical experience provides a better explanation than theory.
The size of the lens does not affect the view of the picture instead it depends on how far you are from the subject. What I am saying is the view of a picture will remain the same even if you change the size of the lens. What will be different is the number of things that will appear in each image that is the scope. Of course assuming everything else remains constant and only the focal length changes.
As I mentioned previously the one way you can grasp this concept of focal length and size of lens is if you experiment with taking various pictures and see the effect.You will be able to find some great DSLR cameras and lenses at any one of these:
