So I am a young photographer (17). I am really into photography, but am consfused on the numbers on the lenses. I see people talk about lens So-and-so 12-345 (or something of that nature). What do the number stand for or tell me?
My mom lets me use her Canon Rebel XTi along with the four lenses she has, but I never really know what lenses to use. Thanks for the help!
the numbers tell you the focal length(mm) of the lens. a small number is a wider lens( you can see more of the landscape or whatever in the photo)
if it has only one number ie 50mm, that is called a prime lens and when you take a photo you may need to move up or back to get what you want in the photo.
if it's something like 28-135 mm that is a zoom lens and you can turn the lens barrel to make the photo take in more scenery ( wide or smaller number) or less of the object ( larger number, narrower view).
the other numbers you see ie f4, f5.6, tell you the largest the aperture will get( in other words how big the opening that lets in light will be)..the smaller the number the wider the aperture and the better the lens will be in lower light. in a zoom it has something like f3.5-5.6 which tells you what the aperture will be at the widest end( in that case the f3.5) to the narrower end( the 5.6) although it usually goes to the larger number( smaller opening) long before it gets to the end of the zoom range.
so 50mm f1.8, good lens for low light( the 1.8) not a real narrow view ( 50mm) but you have to move to change the view( move forward tomake it more narrow, back to make it wider
while 28-135 f3.5-5.6= zoom lens with widest angle at 28mm. f3.5, narrowest angle at 135mm and f5.6 so versatile lens( some call it a walk around lens since you could pretty much just leave it on your camera and it would be ok for most situations you would normally come across) but not very good in low light
check this out to see how focal lenghts differ as well as lots of info in the learning center about lenses in general
http://www.tamron.com/lenses/learning_center/tools/focal-length-comparison.php
the f number also tells you how much sharpness the photo will have ie sharp front to back( f20 ) or blurry background (f1.8) but that is another story
what lenses does she have?
a wide angle( smaller mm number is good for something like landscapes, a bigger mm is good for something like nature shots where you can't really get close to the subject, close up shots, something you really want to highlight just a part of the overall scenery
