Question

[NeoMikel]

Okay, so I've been teaching myself about camera's using many websites. One thing I don't get is this: (newbie question)

I know all about apertures, f-stops etc etc.... and I get that there's a certain amount of mm and f-stops on a lens.... but I'm wondering if say a lens is f/4-6.4 and 24-105mm... that means that I can ONLY do f4 to f6.4 and only go between 24-105mm?

It seems limited when a lens says f2.8... or does the actual camera body allow me to go more/less than that, or am I limited to f2.8?

Sorry if I'm not making any sense... I'm just trying to understand.

Thanks guys. Ask any questions about what I said if I'm confusing

 

[Peanuts]

The apertures 'combined' with the length of the lens are the largest apertures which can be obtained with that specific lens. The smallest number being for the shortest end (in this case f/4 to 24mm) and the largest to the longest (f/6.4 to 105mm). Somewhere in between will be the f/5.6 etc. These apertures are not the only f-stops which can be used, as you can go to the smallest aperture your camera will allow, but not larger (In this case at 24mm, you couldn't achieve f/2.8 )

Hopefully this helps some. Someone else will probably be able to straighten out any terminology I might have mixed up and give a clearer picture.

 

[KevinR]

What that means is that at say 24mm the maximum fstop is going to be f4. But at 105 the maximum fstop is going to be f6.4. As you zoom to 105 you are gradually letting in less light. A lens that is 28-85 f2.8 is that the lens will have a maximum fstop of 2.8 through out the zoom range. Minimum fstops will always be there for any of these lenses.

Hope this helps.:thumbup:

 

[Big Mike]

That's right. The listing on a lens is the maximum aperture. When there is a range (F4-6.4)...that means that at the widest focal length...the maximum aperture is F4...but at the longest focal length...the maximum aperture is F6.4.

On most lenses you can adjust the aperture...just not any bigger than the maximum.

Where is says 24-104mm, that is your focal range (zoom).

 

[NeoMikel]

Wow this helps a tonnn guys. Thanks a bunch! It makes so much more sense now.. and I couldn't find any information like this anywhere.

Once again, thanks!