zoom lengths

iknowdatalfabat · Jul 19, 2008

How do you know how far a zoom can reach?
I used to think 70-300mm told you that but now i know that it's the focal angle.

Rogan · Jul 19, 2008

all 70-300's will reach the same distance
same with any 17-50
18-70 etc etc

when your at 300mm not matter what 300mm lens you use you will be looking at the same picture (removing IQ etc etc)

there isnt a way to say exactly how far you can reach depends on the subject really

iknowdatalfabat · Jul 19, 2008

yeah but do 70-300s reach the same distance as 24-70s?

Rogan · Jul 19, 2008

no, a 24-70 zoomed in fully will reach the same distance as a 70-300 not zoomed in at all

flygning · Jul 19, 2008

As I understand it, it also depends on the camera you are using-- if you use a 70-300mm lens on 2 different cameras, each with a different sensor size, it will affect how "zoomed" the picture looks at any given focal length. Please, however, correct me if I'm wrong (I'm still learning too).

tirediron · Jul 19, 2008

No. A 70-300 starts where a 24-70 ends.

iknowdatalfabat · Jul 19, 2008

focal length AND zoom length?

flygning · Jul 19, 2008

I think to calculate your actual zoom, you have to divide the largest focal length of the lens by the smallest. However, that won't actually tell you how "far" the lens will reach, just how much farther your largest focal length will reach than the smallest one does.

iknowdatalfabat · Jul 19, 2008

sooo does that mean that 200/18=11.11 so the zoom is 11x magnification?

Rogan · Jul 19, 2008

yes your right about that

and it does depend on your cameras sensor, a 70-300 will be differant on a canon dslr to a nikon dslr, to a 35mm camera

iknowdatalfabat · Jul 19, 2008

I have a Nikon D40. So what does that mean for the zoom?

Josh66 · Jul 19, 2008

iknowdatalfabat said:
sooo does that mean that 200/18=11.11 so the zoom is 11x magnification?

I think that's what they would call an 11x zoom, but it's not actually 11x magnification.

The long end is 11 times longer than the short end, but you're probably not going to be anywhere near 11x magnification. You will just have a smaller field of view.