Top: Wide angle; Bottom: Telephoto. Duh

I had always wondered what does 12x optical zoom (or 36-432mm equivalent) means and I had taken photos with and without zoom to compare with my eyes, just like the ones above.

Finally, I took some time off to do an estimated comparison to find out what it really means in layman terms by cropping and comparing.


100% crop of the windows at wide angle. Image size = 18x29 pixels


100% crop of the same windows at telephoto (12x). Image size = 204x340

A simple punch in calculator will mean that the telephoto is 11.3 times wider and 11.7 times taller than the wide angle version. This is remarkably close to 12 times (given the large margin of error by simply doing rectangular selection and cropping to it in this poorly performed test. Not forgetting the less than level image taken with hand). So in other words, 12x zoom really means making your image appear 12 times larger in length or breadth (or 144 times larger in area)

Which brings me back to the smart zoom of up to 48x in VGA mode (640x480) in H1. The 5M mode is 2592x1944, or 4.05 times larger in length and breadth compared to VGA. That's why smart zoom can offer up to 48x in VGA mode since it is almost the same as cropping from the 5M version.

Maybe next time when I'm free i can explore the solid angle of view captured by this camera (in comes remote sensing knowledge). Well, at least found some use of undergraduate physics in my everyday life.

Tagged: singapore dsc h1 physics