Lens manufacturers love to spout the specs of their lenses. Among these specifications hides the "magnification factor", which is especially important to macro photographers. This number often looks like a cryptic ratio, 0.25:1 or 0.5:1. Most photographers know that the closer the number is to 1:1, the more it magnifies images at close focus. But what does that number really represent? Erez Marom shares some of his insights into this mystery in the following article.
Erez Marom writes:
To understand the concept of magnification, it's worth taking a very brief look at how a photographic image is created. Every point in a given scene reflects light rays. The front element of the camera lens 'captures' these rays and then focuses them onto the imaging sensor, producing a projection of the scene at the location of the sensor.