Camera Hacker

:

Add Comment | Related Links | TrackBack
Related Content

Teleconverter Magnification Comparison

A posible reason is that Sigma might be basing their converter rating on image area, while Olympus might have used a focal length multiplier. A doubled focal length makes lines appear to be twice as long, but areas four times as large. Areas are a square of linear dimensions, and it just so happens that 2, the Sigma rating, is the square of 1.4, the Olympus rating.

For example, let's say you took a picture of a 2"x2" cube with a digital camera using a 50mm (equivalent) focal length. Let's assume the sides of the cubes are 400 pixels long, so the surface area of one side is 400*400=160000 pixels. A focal length multiplier of 1.4 gives us 70mm, and sides of 560 pixels. Squaring that we get 313600 pixels for area, pretty close to twice of 160000.

Andrea Reina
Thu, 29 Dec 2005 09:23:10 -0800

<< Back to Article

Add Comment | Related Links | TrackBack
Related Content

Did your message disappear? Read the Forums FAQ.

Add Comment

Spam Control | * indicates required field
Your Name: *
E-mail:
Remember Me!
Comment: *
File attachment is optional. Please do not attach a file to your submission unless it is relevent.
Attach File:
(20 MB Max)
Spam Protection: * Answer of 5 + 4?
Click button only once, please!

TrackBack

TrackBack only accepted from WebSite-X Suite web sites. Do not submit TrackBacks from other sites.

Send Ping | TrackBack URL | Spam Control

No TrackBacks yet. TrackBack can be used to link this thread to your weblog, or link your weblog to this thread. In addition, TrackBack can be used as a form of remote commenting. Rather than posting the comment directly on this thread, you can posts it on your own weblog. Then have your weblog sends a TrackBack ping to the TrackBack URL, so that your post would show up here.

Messages, files, and images copyright by respective owners.