Focal Length and Different Viewpoints
This exercise requires me to photograph a subject using both a wide-angle and telephoto lens with the difference between the two focal lengths as large as possible. The task instructions are:
Find a scene that has enough space in front of it to allow you a choice of viewpoint, from near to far. Avoid a flat subject; it must have some depth – a building will do, or a person in a setting. Start with the telephoto lens and make a tightly framed composition – that is, with the subject filling the frame. Study the view through the viewfinder very carefully, and remember the limits at the edges of the frame. Take your shot. Change lenses to the wide-angle. Then, in a straight line, walk forward, looking through the viewfinder until the same subject fills the frame. Take the second shot.
For this exercise I went down to Antrim town centre to photograph the old castle gate way. Shot one was taken at a focal length of 80mm from a distance of about 100 meters and from my eye height of about 175cm, whereas, shot two was taken using a 12mm fish eye lens (hence the slight vignette around the edges) from a distance of about 15 meters also at my eye level.
There is a very marked difference between both shots even though the main subject, the castle gate, takes up roughly the same proportion of the frame in both. Below are the main differences between each shot:
- The angle of view of the gate
- The vertical towers
- The horizontal parapets
Angle of View
In shot one the view of the gate is very flat, there is no obvious difference in distance between the top and bottom of the gate towers to the viewer. However in shot two, there is an obvious difference, the viewer is looking up at the gatethe view is from my eye level in both. This is due to being considerably closer to the subject in the second shot causing me to look up slightly to include the top of the subject in the image.
The Vertical Towers
In shot one, the towers are parallel to one another and perfectly vertical, however in shot two the towers seem to converge towards each other due to angle of view and seem to get narrower towards the top caused by distortion in the lens.
When viewing any scene, objects closer to the viewer appear larger. Take a row of identical cars leading away from a viewer for example, the car nearest the viewer will be the largest of them all, gradually the cars further away will look smaller and smaller until the furthest away is the smallest of them all. In the case of the gate towers, the top and the bottom of the towers in shot one are roughly the same distance away from the viewer making the tower look the same size all the way up. However in shot two, the top of the tower is further away from the viewer then the bottom, therefore, the top of the towers look smaller then the bottom of the towers.
The towers appear to be bent and converging towards one another in shot two this is due to lens distortion.
The Horizontal Parapets
The parapets in shot one are perfectly horizontal, however with very close inspection of shot two it can be seen that there is a slight cure in the line of the parapet. This again is due to lens distortion.
I like both images for their various qualities however I prefer shot one. This is an exact representation of how the castle gate looks to a viewer and would potentially be well used in a travel guide. However if I were looking for an image that gave a sense of foreboding or controlling I would use the second image. With a few lighting tweaks this could be well placed to illustrate a book/story of some kind.
Conclusion
A lens with a longer focal length/telephoto lens will cause a flattening of perspective, where a wide-angle lens will cause a distortion of perspective in some cases to the extreme. This will be useful to remember in future work when potentially needing to emphasize size or distance.
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