mm to X

[perfectpixel]

Ok, so I get asked this a lot and am not sure what the answer is:
How to you convert lens focal length mm to magnifications factors (ie X)
I have had too many friends brag that their new P&S digicam has an 10X magnification, etc

now in the traditional world,
50mm is normal, so
100mm would be 2X
is 4X then 200mm or 150mm?
what X is 400mm? 8X? :roll:

geeze o'pete!

[OviV]

If your friends PS has a lens that goes from 10 mm to 100 mm then it is considered a 10x zoom in the PS world since 100 MM is 10x as much as 10 mm. It really does not mean much since as you can see it does not really tell you how close you can zoom but rather the zoom range. If you were to use a 100-400 lens on your camera you would be able to get much closer even though that lens would only be a 4x.

Ovi

[nosquare2003]

now in the traditional world,
50mm is normal, so
100mm would be 2X


For binoculars world, yes it is.

For camera lens, please refer to Oviv's post.

[Persian-Rice]

Oviv, gave the perfect answer...........

I guys Drisley is absolutely screwed, he has a bunch of 0x lenses lol.

[timmyquest]

Oviv, gave the perfect answer...........

I guys Drisley is absolutely screwed, he has a bunch of 0x lenses lol.

1x lenses ;-)

[Ballen Photo]

If your friends PS has a lens that goes from 10 mm to 100 mm then it is considered a 10x zoom in the PS world since 100 MM is 10x as much as 10 mm. It really does not mean much since as you can see it does not really tell you how close you can zoom but rather the zoom range. If you were to use a 100-400 lens on your camera you would be able to get much closer even though that lens would only be a 4x.

Ovi

Sigma's 50-500 lens would be another perfect example of a ten times lens also.
Ten times is quite a stretch for a lens. :shock:
-Bruce

[Persian-Rice]

Oviv, gave the perfect answer...........

I guys Drisley is absolutely screwed, he has a bunch of 0x lenses lol.

1x lenses ;-)

oh shutup! :D

[timmyquest]

Oviv, gave the perfect answer...........

I guys Drisley is absolutely screwed, he has a bunch of 0x lenses lol.

1x lenses ;-)

oh shutup! :D

Whhaaaat


I wouldnt invest in a 0x lens, i think they call 'em extension tubes :lol:

[ron chappel]

Actually the answers you've got don't quite tell the whole story.

The zoom ratio of the lenses are as everyone has said-
i.e a 35-70mm zoom is 2x,a 100-300mm zoom is 3x,etc

BUT..there's also true magnification
A focal length of about 30mm on a normal digital SLR gives the same magnification as the human eye *

so...

a 90mm lens is like looking through 3x binoculars
... a 300mm lens would be like looking through 10x binoculars
...a 500mm lens would be like 16.5x etc



* so why isn't magnification the same if you look through the camera with one eye and keep the other eye open (with a 30mm lens on the camera) ??
It's because the viewfinder has it's own optics which confuse the issue....

[MarkH]

Ok, so I get asked this a lot and am not sure what the answer is:
How to you convert lens focal length mm to magnifications factors (ie X)
I have had too many friends brag that their new P&S digicam has an 10X magnification, etc

now in the traditional world,
50mm is normal, so
100mm would be 2X
is 4X then 200mm or 150mm?
what X is 400mm? 8X? :roll:

geeze o'pete!

When you have an SLR you just explain that you can change the lens to suit your shooting situation. You can use a lens that goes to 10mm or one that has 1200mm. Therefore your camera is able to have a 120x magnification, or more if you count teleconverters.

A camera that doesn't have interchangeable lenses is much more limited, even with a 10x lens.

Some 10x zoom cameras offer 38-380mm equivalent, the Canon EF-S 10-22 lens will provide 16mm equivalent at the wide end when used with one of the 1.6x cameras. That is a huge difference on the wide end.

10x zoom? Is that all? My 10D gives me the ability to have 120x zoom, or 240x if you count teleconverters. And no I am not talking about digital zoom, I'm talking true optical zoom!

[RichardtheSane]

10x zoom? Is that all? My 10D gives me the ability to have 120x zoom, or 240x if you count teleconverters. And no I am not talking about digital zoom, I'm talking true optical zoom!

I believe there is an 8mm fisheye lens out there, so technically you can have a 150x zoom, and 300x + with just one teleconvertor. You can stack teleconvertors.....

Just a thought

[timmyquest]

10x zoom? Is that all? My 10D gives me the ability to have 120x zoom, or 240x if you count teleconverters. And no I am not talking about digital zoom, I'm talking true optical zoom!

I believe there is an 8mm fisheye lens out there, so technically you can have a 150x zoom, and 300x + with just one teleconvertor. You can stack teleconvertors.....

Just a thought

1.4 tcon=140x
2 tcon=200x
1.4+2=240x

[OviV]

Actually Timmy,

1.4TC = 1.4 x
2.0TC = 2X
1.4+2TC = 3.4X

[Ballen Photo]

Actually Timmy,

1.4TC = 1.4 x
2.0TC = 2X
1.4+2TC = 3.4X

True story. :wink:
-Bruce

[timmyquest]

I was thinking percentages :oops:

[aznkid.com]

just find out the 35mm equiv of his camera (i usually find this on stevesdigicams.com) and compare to yours...

let's take the S1 IS for example..
the 35mm equiv is: 38 - 380 mm

so when your friends brag about 10x zoom, i assume they're bragging about how far they can get instead of the RANGE (what it actually is.. 380/38 = 10)

take for example my 75-300mm lens (4x zoom because 300/75 = 4).. multiply that by the 1.6x factor, i get 480mm.. farther than they get with my 4x zoom lens ;)

go bring them to a camera store and try out a 600mm prime and tell them it's only 1x zoom ;)

[pcasciola]

Am I missing something? Isn't this basic math?

1.4x + 2x TC = 2.8X

For example, put a 2x TC on a 100mm lens and you have a 200mm, right? So put a 1.4x TC behind that and you get a 280mm, 2.8 times your original lens (or magnification, whichever).

[timmyquest]

Am I missing something? Isn't this basic math?

1.4x + 2x TC = 2.8X

For example, put a 2x TC on a 100mm lens and you have a 200mm, right? So put a 1.4x TC behind that and you get a 280mm, 2.8 times your original lens (or magnification, whichever).

corectomundo

[pcasciola]

Am I missing something? Isn't this basic math?

1.4x + 2x TC = 2.8X

For example, put a 2x TC on a 100mm lens and you have a 200mm, right? So put a 1.4x TC behind that and you get a 280mm, 2.8 times your original lens (or magnification, whichever).

corectomundo

Ok, but then what was this:

1.4 tcon=140x
2 tcon=200x
1.4+2=240x

and this:

1.4TC = 1.4 x
2.0TC = 2X
1.4+2TC = 3.4X

[OviV]

Ok, but then what was this:

1.4 tcon=140x
2 tcon=200x
1.4+2=240x

and this:

1.4TC = 1.4 x
2.0TC = 2X
1.4+2TC = 3.4X

I guess Timmy and I are the product of our inferior educational system. :lol:

[tofuboy]

Oviv, gave the perfect answer...........

I guys Drisley is absolutely screwed, he has a bunch of 0x lenses lol.

1x lenses ;-)

oh shutup! :D

Whhaaaat


I wouldnt invest in a 0x lens, i think they call 'em extension tubes :lol:

I'm happy with my 0x investment :) I'm also happy with my 4.?x investment, and my 1x investment... and I can't wait until I make my 2.?x investment.

[pcasciola]

I just bought an f/6.3 reducer to shoot the eclipse through an f/10 scope which had too much magnification to fit the moon in frame, which is roughly a -1.4x TC. Negative zoom, how's that for a waste?

Man, this sure is becoming a silly thread. :roll: