# mm of lens and magnification

Status
Not open for further replies.

#### oxygn

##### New Member
hey guys,

what mm of lens would give you a magnification of 1x?

?mm = 1X
?mm = 2X
.
.
.
.

Thanks,
Colin

#### espn

##### Deregistered
X is counted by the total zoom divided by the widest zoom.

70-200mm = 200/70 = 2.8X, 1X = 70mm.
28-70mm == 70/28 = 2.5X, 1X = 28mm.
500mm = 500/500 = 1X, 1X = 500mm.

And so on.

In short, "X number of zoom", this phrase, is totally useless. The actual full range known is much better.

#### reno77

##### New Member
"Magnification
Lens magnification is calculated relative to the normal 50mm lens. With a 50mm lens, a 6 man will fill the frame at 8. A 20mm lens is about half the focal length of the 50mm lens, and therefore has a magnification of 1/2. A 6man will fill the frame at about half the distance, or at about 4. A 400mm lens is about 8 times the focal length of the 50mm lens, and therefore has a magnification of 8. A 6 man will fill the frame at about 64.

The standard or normal field of view of the human eye is about 40 degrees. This is about the horizontal field of view of the normal 50mm lens. A 20mm lens is about half the focal length of the 50mm lens and has a field of view about twice as wide, or about 80 degrees. A 400mm lens is about 8 times the focal length of the 50mm lens and has a field of view about 1/8th its width, or about 5 degrees. "

Taken from http://www.shutterfreaks.com/Tips/LensSelection.html

#### oxygn

##### New Member
THank you all=)

Colin

Status
Not open for further replies.