The D(i)S(ney)LR Series: Know Your Camera - (3) Perspective
Focal length. This single aspect of photography can have the most profound effect on your images. Not to be confused with focal distance, focal length is a tiny measurement in millimeters that can change everything from your perspective to the apparent size of the space you're shooting. Pretty remarkable, eh?
The first step to understanding Focal Length is to understand your own vision and how it works. What is Human Perspective and how can you directly duplicate it in photography? So everybody: look up from your laptop wherever you may be and cover one eye. Get a good feel for what you're seeing. Human Perspective is considered duplicated by a 50mm lens, although between 35-50mm are all considered reasonably accurate to human perspective by the naked eye.**
**[Cropped sensor cameras will have a multiplier effect on focal length, specifics dependent on the camera model and whether the lens in use is designed for cropped sensors.]
The two main concepts related to focal length and perspective to understand are Field of View (also called Angle of View) and Perceptual Distance.
Field of View refers to the entire area that is visual in your frame. So, when you open one eye, everything that you can see. The lens is your camera's eye. The shorter your focal length, the WIDER your Field of View, and vice versa.
Different people will tell you different things, BUT generally speaking we can consider "wide" focal lengths 28mm and below...
Human perspective to be around 35mm-65mm...
Ideal "portrait" focal length to be 70mm-105mm...
And telephoto/distance to be over 105mm.
Cell phones usually come with wide angle lenses attached. This is what allows you to take a selfie with a large group of people from a distance away as close as the end of your arm. Many DSLR's include a stock lens with a focal length range of 18mm-55mm. This is a very versatile range for shooting things that are reasonably close to your camera. Be aware that the shorter your focal length is, the more the outside areas of your photo will bend/distort to accommodate the wider field of view into your frame (think of Fish Eye, the most exaggerated example of this phenomena).
When it comes to practical use in the parks, I am spoiled by the zoom lens I have: 28mm-300mm. I can shoot almost any scenario at Disney with that focal length range. The 28-85mm is a great range for character interactions or walking parade performers, while 85mm+ is great for stage shows and parade details. I've used a 70-200mm to shoot parades before, but I find myself getting frustrated without being able to pull out wide enough for performers or pieces of floats that are closer to me. Honestly the shorter zooms (18-55mm, 18-150mm, 28-105mm, etc) tend to be the most useful in the parks, with the one exception being if you want closer detail for stage shows.
The other concept associated with focal length (and the one that might be slightly more abstract to understand) is Perceptual Distance. Perceptual distance refers to how far apart objects appear on the Z-axis. Did I lose you yet? Ok, let's go back to looking out at your room through one eye. How far are you from the nearest window? Is there a couch between you and the window? How far apart are those objects from one another? At 50 mm, distances on the Z-axis mimic reality. As you go to shorter focal lengths, perceived distances on the z axis appear larger...
...while longer focal lengths will compress distances on the z-axis.
This is why we think of "portrait" focal lengths to be around the 85mm range.
This is considered the most flattering focal length to the face. Short focal lengths and their effects on the Z-Axis tend to exaggerate facial features.
Now that we've got the three main pieces of the photography puzzle, future articles will get into some more specific items such as Macro photography, primes vs zooms, sensor sizes, shooting RAW, Lightroom, etc. If you have specific topics you want covered, shoot me an email! I'd love to hear from you. MinkFlamingos@GMail.com