Re: Wide angle, long lenses and orthographic views – The main difference between ANY camera lens designation except perhaps extreme telephoto (say 300mm+) is that ortho views show absolutely no perspective convergence, while any lens shows at least some. In long lenses (say 80mm and above), the perspective is flattened somewhat, but not eliminated entirely. The principal reason longer lenses are used for portrait photography is not because they look more like ortho views, but because they better portray facial proportions as they are perceived by the human eye/brain combination. Wider angle (shorter) lenses have more pronounced perspective effects, so foreground objects appear proportionally larger than with longer lenses covering a similar field of view. In portraits, the nose is a foreground object and wider lenses make it look too large in relation to other features. The same perspective considerations broaden the face and produce other less desirable visual effects.
But an ortho view is just as distorted because there is NO perspective, so items farther from the camera do not diminish in size. Our eyes do perceive perspective so ortho views look odd and distorted, particularly when the extremities are viewed close to the camera and the rest of the body farther away – the expected perspective size difference is missing and make the proportions look completely bonkers.
Early large-format cameras did not have this problem of lens choice as seriously as more modern smaller-format (like 35mm) film cameras. Lenses were generally fixed and seldom interchangeable. But progress made for smaller cameras and more portability, and eventually different lens choices. This introduced other factors in producing recorded visual images. The smaller the exposed film plane in a camera, the more perspective effects, and thus lens choice, affect the image outcome. For the very common 35mm SLR film camera, it quickly became a common “standard” to say a 50mm lens is a “normal” lens, but for a large format camera, 50mm focal length is fairly wide angle, and for small digital sensors, it’s considered a long lens. With digital cameras, small sensors can produce pronounced perspective effects. So beyond mere focal length, the area of exposed film/sensor comes into play when determining the best lens for a particular job.
For figurative work, when it’s important to portray the body’s proportions without undue distortion, a longer lens is a good idea. I often use an 80mm setting for 1080p rendering in Blender. But wider lenses can be more dramatic because of their more pronounced perspective effects, whereas a longer lens can look more “documentarian” and “reportorial” because of the flattened perspective they portray. All of this is a matter of human perception, so studying that is also helpful when working in a field where lens choice is another tool of the trade.