Simple guide to lenses?

Skipraider

Skipraider

Messages
114
Edit My Images
No
Has anyone got a simple guide to what the numbers mean on a lens, f stop etc?

Was thinking about getting a new lens but need to reseach what i'm doing first!

Any help appreciated!


These lenses on Ebay look like a good price, any reason why?
 
I would suggest a book would be a good place to start.

Understanding Exposure by Bryan Peterson would be my suggestion!

Those lenses would probably be okay for casual amatuer hobbyist use but they are low priced for a reason. In photography much as in anything else, you tend to get what you pay for, so they may not be as fast, durable or sharp as better quality lenses, but under the right conditions and used in the right way they should be capable of decent results.
 
I can tell you....

a lens will generally be referred to as a 18-55 3.5-5.6
The first two numbers are the focal length range. If it is a prime you will only get one number. The so called "zoom" can be worked out by dividing the larger number by the smaller one (55/18=3x zoom) but really focal lengths are far more relevant.

The second two numbers are the f stop range. Some lenses will have a constant maximum aperture (70-200 f4 means that the widest aperture available is f4 throughout the focal length range). If there are two numbers the first number refers to the f stop at the wide end of the zoom. The second number refers to the f stop at the long end of the zoom. So, in the case of our 18-55 3.5-5.6 we could shoot at 18mm and f3.5 or 55mm and f 5.6. We could of course choose smaller apertures. In between the widest and longest ends of the zoom you will have an inbetween value as the max aperture. Eg 35mm f4.
Hope this clears things up.
I should add that there are often a number of letters after the lens. You will ahve to google these, there are rather a lot. The most notable are probably
IS= Image Stabilisation (Canons technology to reduce the effects o camera shake)
VR=Vibration reduction (exactly the same but Nikon lenses)

All the best,

Alex
 
Yeah thanks, that's a help.

How do the Sigma lenses compare to the standard 18-55mm in terms of quality?

I am a amatuer hobbyist so it really isn't worth me spending £££ on fantastic lenses. I'm just wondering at the minute if it is worth me buying some lenses like the one above to give me more flexibility, or just keep the standard kit lens.
 
Look to increase your focal range ie: 55-250mm zoom, this will give you more range and freedom to experiment, (18-250 effective range). Of course it really does depend on what you intend to photograph though.
 
If you don't know what the numbers mean then you don't need a new lens.

Get to grips with what you have, read a couple of books and go take pictures to experiment with what you've learnt
 
...and generally the smaller the number the higher the $$$ !
 
You must log in or register to reply here.
Back
Top