Forum: Poser - OFFICIAL


Subject: focal length experiment

picnic opened this issue on May 08, 2000 ยท 33 posts


jval posted Tue, 09 May 2000 at 9:25 AM

Diane, I'm surprised that you hadn't played much with camera focal lengths. In the real world knowlegeable photographers almost never use the wider angle lenses, or even standard, for portraiture unless they are after a special effect. Generally they will choose something between 70mm & 100mm (on 35mm cameras). This is because wide angle lenses do not merely include more in the picture frame but also have a dramatic effect on perspective. Filling the camera viewfinder with someone's face while using a wide angle lens will result in large bulbuous noses with smallish ears that appear farther than they should be. Visual exaggeration occurs as close objects appear larger than normal & farther objects become smaller than normal. Conversely, telephoto lenses will tend to flatten the image and in fact the farther something is, the larger it will appear in proportion to foreground objects. In the case of portraiture, this will allow you to fill the frame with a headshot while still keeping realistic looking ears and noses. Experienced photographers will often choose wide or telephoto lenses precisely for this reason rather than simply getting more into a picture or bringing something closer. (You may have noticed this telephoto effect if you've ever watched a tv news feature focusing on a single speaker in the middle of several rows of people. The speaker appears quite normal while people 5 or 6 rows back may appear rather larger than they should be.) Actually, in real life our eyes see the same thing but our brains know better and automatically make the corrections for us no matter how close or far we are from our subject. A camera won't do that and our brains do not make the same adjustment for flat images. I think this effect is not so obvious within Poser because we can modify facial features. If our focal length is too wide (also called short) we can alter the nose or whatever so that it still looks okay. But if you then choose a very different focal length you may find that the facial features change significantly. In 35mm photography the standard lens is 50/55mm. This is a compromise that is supposed to show the world as we see it from normal distances. You might find it instructive to set up a figure at the 50mm focal length. Then leave the figure untouched while you view it from different angles, distances and focal lengths. You should quickly catch onto the possibilities and this may add an entirely new technique to your bag of tricks. BTW, nice image.