Perspective on Paihia

Changing focal length in Paihia, New Zealand.   

If you go to New Zealand, and happen to visit a quaint little area known as Paihia, you will find this sword fish statue posing for your shots at town center.  I photographed the above images using a Panasonic FZ2500, a bridge type camera with a one inch sensor.  The actual focal lengths were quite a bit lower, at 8.8 mm for the wide angle shot and 60.4 mm for the telephoto shot.  The crop factor for the camera is 2.72, meaning that if you take any actual focal length for the lens and multiply it by its crop factor number, you will get the relative focal length on a full frame digital camera.  So in this case, 8.8 mm (actual focal length) times 2.72 (the crop factor) gives about 24 mm (the relative focal length).  A full frame digital camera with a 24 mm lens will give the same field of view as a one inch sensor camera using an 8.8 mm lens.

In order to get this type of photo you need a couple of things.  First of all you need a camera with a zoom lens which has the ability to change its focal length from a wide angle  to a telephoto.  Then you need two subjects, one closer to you and one farther away.  Lastly you have to position yourself so that you are close to the front subject with the back object lined up in the camera's viewfinder.  When that is all done, you are ready to go on to the next phase of the shot.

At this point you set the camera's lens to a wide angle value; generally accepted as being below or at 35 mm relative.  In this case I used a 24 mm setting.  I was close to the sword fish and made sure the island at the back was in my viewfinder.  Click.  The first shot is done.

This then is the key.  You have to move back and zoom in.  The distance you move back depends upon a lot of factors.  Without getting into details, it is all based upon ratios.  The zooming in enlarges the foreground subject.  If you zoom in the right amount that object should be the same size in your viewfinder as it was in the original shot.  Since the distance between the foreground and background object has not changed, the background appears larger relative to the foreground.  This is called compression because it looks like you are compressing the distance between the two subjects.  Again, it is all based upon ratios.

Click.  The second shot is now complete.

If you did this right your foreground in both shots should be about the same.  The background will look significantly closer though in the second shot - it is quite an earth-moving experience.