‘Find a scene that has depth. From a fixed position, take a sequence of five or six
shots at different focal lengths without changing your viewpoint. (You might like to
use the specific focal lengths indicated on the lens barrel.)
As you page through the shots on the preview screen it almost feels as though you’re
moving through the scene. So the ability to change focal lengths has an obvious use:
rather than physically moving towards or away from your subject, the lens can do
it for you. The other immediate difference between the shots is the ‘angle of view’,
which also depends on the sensor size of your camera. Use the sequence to try to
get a feeling for how the angle of view corresponds to the different focal lengths
for your particular camera and lens combination. Which shot in the sequence feels
closest to the angle of view of your normal vision?’
‘Does zooming in from a fixed viewpoint change the appearance of things? If you enlarge and compare individual elements within the first and last shots, you can see that their ‘perspective geometry’ is exactly the same. To change the way things actually look, a change in focal length needs to be combined with a change in viewpoint.’
18mm cropped to match 55mm
It’s hard to say which focal length is closest to my own eyes, not helped by the fact that my own eyes are, medically, a mess, (iritis, vitreous detachment and retinal laser surgery… if you’re interested), but 24mm seems to fit.
Comparing the cropped 18mm with the 55mm is very enlightening. I didn’t get the crop exactly right, having left in a little too much of the image at the bottom, but it’s close enough to see that, resolution aside, the images are the same.
Reading the part in the coursework about the scene in Blade Runner (Dir. Ridley Scott, 1982) irritated me. Blade Runner being a film I’m very familiar with (autistic tendencies led me, in my teens, to watch the film on a daily basis for several years, to the point that I have seen it over 1000 times… not kidding).
The course material drew attention to the fact that the ‘Esper’ machine, when zooming in to extreme close-up, dissolved into grain instead of pixels, using this as an example of how in 1982, Scott’s view of the future of photography was flawed. That is a fair point, but the scene itself is entirely impossible, as the machine, when moving around the view in the photograph, was able to show objects that were obscured from view. You were able to see objects that were behind other objects.
Now three dimensional scans of rooms and spaces are entirely possible, even with current technology, but the idea that you can get such information by using a fancy machine to scan what is effectively a polaroid… while it was necessary for the film plot, for me, as any kind of commentary on photography, rendered that scene utter nonsense.
Okay, I’m just being picky, because the point itself is fair enough. Ridley Scott didn’t predict digital photography, but… (grumbles) 😉