Go Back   Steve's Digicams Forums >

LinkBack Thread Tools Search this Thread
Old Jan 5, 2004, 12:35 PM   #1
shoelessone's Avatar
Join Date: Oct 2003
Posts: 71
Default So I am curios, what is the "zoom" equivalent of a

I just sold my G3 and purchased a Digital Rebel. I am very curios what the equivalent zoom number is for the 18-80mm lens... Is I am sure there is some simple formula. If not, then could somebody also tell me what the zoom number equivalent is of a 75-300mm zoom lens would be?

Also, to clarify by "zoom number" I am refering to the number the Point and Shoot Dcameras bost, for instance my G3 had "4x zoom".

Thanks much
shoelessone is offline   Reply With Quote
Sponsored Links
Old Jan 5, 2004, 2:01 PM   #2
Senior Member
PeterP's Avatar
Join Date: Jul 2003
Posts: 3,397

The zoom number on P&S is pretty silly actually.
It is just the lenses max/min FL, so if the lenses minimum is 10mm and its max is at 40mm you have a 4x zoom. Almost meaningless to actual magnification

Your 75-300 is a 4x lense and the 18-80 is a 4.44x lense.

It is a great marketting tool though

What you really need to work out is your camera magnification factor. For the sensor in the canon EOS dRebel and d10 I believe it is 1.6 so your 75-300 lense works out as a 120-380 35mm equivelant lense and the 18-80 is 28.8-128 at 35mm equivelant.

This is why it s tough to get really wide angle lenses for most of the digitals.
PeterP is offline   Reply With Quote
Old Jan 5, 2004, 9:50 PM   #3
SpeedyManiac's Avatar
Join Date: Aug 2003
Posts: 74

If you're trying to figure out what the magnification of the lens is, just take the longest focal length and divide it but the shortest focal length, so the 75-300mm lens is 4X, the 18-55mm lens is a little over 3X. Knowing the magnification is actually pretty useless, knowing the focal length is better. With a digital SLR, most have a magnification factor due to smaller sensors, the Digital Rebel has a 1.6X magnification factor, so it's like putting a 1.6X teleconvertor on a 35mm SLR.
SpeedyManiac is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -5. The time now is 9:45 AM.