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So thats why I`m going to put my neck on the block and ask a silly question....

With a lens that has a 3.5 - 5.6 speed, how come sometimes the camera wont allow you to get the speed at its fastes when composing a shot?

For example, I have it set on manual and set the shutter to for talking sake 1/250, sometimes the camera wont allow me to open the apeture any more than 4.5 (just guessing figures here) but I have noticed that at times I am prevented from getting a maximum opening of the apeture.. Is this something I have set wrong in the camera, or is that how they are designed?

I refer to the lens kit here.

Thanks

I think it would depend on the focal lenght you have the lens set to.
For example, if the lens is a 70-300 f3.5-5.6 and you have the lens set at 300mm you can't select anything lower then f5.6

NewbieD70 wrote:Is this something I have set wrong in the camera, or is that how they are designed?

Nope, it's just how they work. As Phillip says, it's f/3.5 at 18 mm, f/5.6 at 70 mm, and... in-between in-between!

Thanks guys... the penny has dropped