Moon Size

This is a quick blog to show the effects of using a different focal length lens on distant objects relative to a foreground object.

A few nights ago I shot the full moon rising out of the sea just south of Napier, in Hawke's Bay.  My goal was to frame the moon inside a newly installed arch / gateway, and to have the moon central in the arch.

Below are 2 of the shots that I came away with that night:

These 2 photos were taken 2 minutes apart as the moon rose.  They are both ( apart from some minor cropping to straighten them etc ) the full image that was taken with the camera.

The photo on the left was taken with a focal length of 107mm ( on my 50-230mm Fuji lens ) and the photo on the right was taken with the same lens at a focal length of 50mm.  After taking the first photo I changed focal length on the lens and walked closer to the arch to frame the second shot to have the arch a similar size as the first photo.

As you can see the moon in the longer focal length photo appears much larger in comparison to the arch than the same moon in the second photo.

This is purely down to the effects of "compression" that you get as you increase the focal length of a lens, where objects that are far away from the camera appear to get closer and larger.  This is one of the reasons that in my landscape photography kit I carry a telephoto lens; so I can distort the size of near and far objects to suit the shot.  It is a very powerful tool to have.

You may ask why I moved closer to the arch for the second photo? Well as the moon rose it also started to move to the left in my frame, so to keep it centred in the arch I would have needed to move to my right, but unfortunately there were some signboards that would have blocked by view of the arch if I had gone any further right, so I had to change focal length and reframe the shot on the other side of the signboards to keep the moon in the centre and have the arch fill most of the frame.