Lenses
The lens is a very important part of your photography kit, it projects the image onto
the film or sensor so invest in some good " Glass " , you get what you pay for.
I recommend that if you wish to expand your lens collection then ask yourself what type
of photography will I use the lens for.
Then go on-line and check the reviews for the lens you are planning on purchasing
before you part with any of your hard earned cash, i.e. www.dpreview.com.
Types of Lenses
Prime Lens - Also known as fast lenses are great for low light, most prime lenses
have apertures as low as f/1.8 and f/1.4 with focal lenghts of 28mm, 50mm, 85mm
and 100mm, the wide angle lens would be great for landscapes while the longer zooms
100mm would be great for portraits.
Wide angle - A wide angle lenses are great for landscape and seascape photography
but can also be used for stadiums, tennis courts and close-up of group scenes typical
focal lengths 10-20mm, 12-24mm, 16-35mm , 17-40mm and 17-55mm . Wide angle lenses
should be used primarily to emphasize foreground detail, getting down low and making
that foreground really stand out.
Standard Zoom - Great for every day photography and travel, most do not have apertures
as low as a prime lens many around f/3.5 or f/4.5 a typical lens would have focal lengths
similar to 24-70mm or 28-135mm. The 24-70mm range makes a great choice for a
landscape lens, the 24mm for wide angle scenes and the 70mm for isolating details in
a scene or compressing together elements in a scene.
Telephoto - Great for sports and isolating parts of a landscape, most have apertures
of around f/5.6 and typical focal lengths of 70-200 or 70-300mm.
Macro - Mostly prime lenses, a macro lens will give you 1:1 image reproduction,
making this excellent for photographing flowers and insects.
Lens Perspective
From a creative aspect lenses have the ability to compress or bloat depending on
which one you use.
A 28mm lens will have a bloating effect on a image, with a landscape scene an object
in the foreground will really appear to stand out within the overall scene.
With a telephoto lens 70mm or greater you will get a compression effect in the scene,
with portrait photo's it will make people look thinner which is why it is favored by studio
and portrait photographers, another aspect of a telephoto lens is when applied to
landscape photography, a telephoto lens will compress elements of a scene together
making them look closer together i.e hills, trees, fences, buildings and signs.
Crop factor and lenses
If you are not using a full sensor camera, then you will have to take into account your
sensor's crop factor i.e. 1.6 that is if you are using a 50mm lens the equivalent focal
length will be 50mm x 1.6 = 80mm, which is one reason why this is one lens that you
will find in nearly every wedding photographers kit.
Every lens has a an aperture where it achieves its sharpest images and this is mostly
at 2 stops above its lowest aperture i.e. on the 50mm f/1.8 the sharpest aperture would
be around f/5.6.
Portrait Lenses
What makes a good portrait lens ?, a good portrait lens would have to a prime lens
with a typical focal length of around 85-100mm and you should position yourself 10-12
feet away from the subject. If you prefer to have the flexibility of a zoom lens then a Nikon
24-120mm lens or a Canon 28-135mm lens would be excellent choices.
Protection
Protect the front lens element of your lens with a uv filter or simply put on a lens hood
to the front of the lens.
Ghosting
Be wary of ghosting on a photograph if you have a UV filter attached to the front lens
element and photographing in low light.
Care when using a Prime lens
If using a prime lens for portrait photography and selecting an aperture value of around
f/1.8 - f/2.4 then the overall zone of focus will be so small that you will need to focus on
the eyes of your subject to ensure this part of the face stays in focus while the rest will
be slightly blurred.