Enough Ps for now.
One common mistake I used to make a long time ago, and continually rears its head is the proper use of wide-angle and telephoto lenses. A common conversation goes like this:
Friend: Can you recommend a good wide-angle lens?
Me: Why, what do you want to use it for?
Friend: Sometimes I can’t fit everything in the frame, so I thought something wider might help.
Me: [wrings hands in the air, launches into a tirade]
Dinner. Any closer and my lens would have been in the bowl of soup. Nikon D3, 14-24/2.8
Rule One: They are NOT to ‘get more into the picture’ or ‘get closer’. That’s absolutely the wrong way to shoot, and will result in far-away looking and very, very boring images.
Why?
It’s all about perspectives. A wide angle lens has a wide angle of view, as the name suggests. This means, that things closer to the lens will be exaggerated in perspective compared to things further away; simply because the foreground subjects of a given size occupy a larger percentage of the field of view. A telephoto lens compresses perspectives; which is to say, a mountain 5km away will appear to be about the same size as one 10km away, because the angle of view of the lens is narrow, and both mountains occupy similar proportions of it – despite the difference in subject distance. It also helps that because of the higher magnification of a long focal length, your subjects are naturally going to have to be much further away.
Ipoh hills at sunset. Nikon D700, 28-300VR.
Rule Two: Choose your perspective before you choose your lens.
If you know how you want the composition of your frame to appear – specifically, the relative prominence of subjects and other supporting elements – then you’ll know whether you need to use a wide-angle (all about the main subject, the rest is required to give context), a telephoto (isolating the main subject, or the main subject is compressed against the background) or something between.
This is one of the great secrets of professional photographers. Look carefully at news or photojournalism images: they’re shot with wide lenses, with main subjects front and center – that’s because the lines of perspective converge on the main subject, and the background is diminished. Give it a try, and you’ll find your images a lot more powerful. MT
So here’s my pet peeve:
“A telephoto lens compresses perspectives…”
No it doesn’t. Standing farther away compresses perspectives.
Depends what you define as perspective. For a given subject magnification, a telephoto compresses foreground and background objects into being similarly sized to the main subject. A wide doesn’t.
The human eye has a fixed focal length, so moving farther or closer changes perspective. A camera can have different focal lengths for the same image area, with which these perspective changes can be simulated. Simulation is the keyword here, as far as I can understand.
Our eyes have a fixed focal length, but we have far more sophisticated processing that allows us to focus on a very narrow portion of the scene, or a wider one, with no apparently loss in resolution. Cameras can’t do this.
I’m with Molch here. Perspective is changed with your feet. The reason a telephoto compresses foreground and background is because you stand further back than you would with a wide, it has nothing to do with the focal length! By moving back, you change the relative distance between camera and subject, versus subject and background.
You actually said it yourself, “for a given subject magnification”, which implies moving when the focal length is changed.
This is actually really easy to test. Take a picture with a telephoto lens. Stand in the same spot and aim the camera at the same subject with a wide angle lens. Zoom in, or crop the wide shot so you have the same framing as the telephoto image, and you will find that perspective is the same.
Perspective is how objects appear in relation to other objects, and magnification does not change this. If one tree is slightly to the left of another tree, I think you will find it will always be like that no matter how much you magnify, as long as you stand in the same spot.
Two images to illustrate perspective change, irrelevant to focal length: http://forums.dpreview.com/forums/post/35180125
Same lens, same focal length, but different distances (cropped in post to match) gives quite a different view.
This sophisticated processing you talk about is the fact the brain can focus attention on part of the visual field, and I guess that’s what I’m trying to say with the word simulation. When you use a tele you simulate focusing your attention on something far away and thus taking up a small portion of the visual field, when using a wide angle you simulate broadening the focus of attention to include more of the visual field, which is indeed a wondrous characteristic of the brain and eyes working together. It’s probably a more subjective take on the topic, but I really like the fact that these discussions can take place here. Much gratitude to you MT!
That would make sense. I remember reading once that the optical system in our eyes is in fact extremely primitive – single element, not very uniform lens, some liquid and a curved sensor – but the processing is massively clever to make up for it. For instance, our retinas have limited resolving power due to the size of the cells, but we make up for that by having muscles that vibrate/ scan the eyeball across the field of view so we are constantly ‘stitching’ an image – the brain does the rest, all in real time.
I wanted to create this site so discussions like this could take place in an environment that was both friendly and objective/ knowledgeable – glad to know I’ve succeeded
This is a semanic disagreement. Wikipedia lists the different meanings of the term perspective, and both Molch´s and Ming´s use are listed. Nikon, by the way, name their tilt-shift lenses for perspection controll (PC) lenses.
actually nothing that you are shooting changes perspective at all if you yourself do not move – a WA shot of distant mountains cropped will have exactly the same perspective as the tele shot … its only with subjects closer at hand that we can actually change perspective significantly, by getting close or moving away AND then using different focal lengths to accommodate the necessary difference in included angle, but if you stand in one spot and simply change focal length, there is no perspective change at all, only a difference of included angle … so in reality, it is your actual physical position relative to objects that controls perspective, not anything inherent in lenses wide or long …
Boy, there are a lot of people not getting it here.
Large part of this article was about the effect of CHANGING THE FOCAL LENGTH OF YOUR LENS, not about where to stand.
I.e: f you are a photo-reporter, asssigned to a certain stand, or vantage point, how can you use the proper lens, with the proper focal length to achieve the result you want?
Molch: if you are covering a ballgame, you are not going to walk onto the pitch to get into the proper spot for a nice close-up of the action (but if you are a tourist taking shap-shots: sure thing).
This article is precise and to the point, and perfeclty correct. Re-read until it makes sense to you, do not try to change the world to fit your incorrect perception.
I will spoon-feed it to you:
Start out with a zoom-lens. Move back and zoom in. Then move forward and zoom out (for a main subject of approx same size on the actual photo).
Next: stay with ONE focal length, take another picture up close and then one further away, and CROP in post-photo (again: until you have the subject appear to be about the same size). Take one good look at the RELATIONSHIP BETWEEN YOUR SUBJECT AND SURROUNDINGS, and if you still do not get it (focal length vs. distance): stick with snapshots.
Best.
Jan
Ming Thein,
It just dawned on me: THIS IS FUNNY AS HELL!
Just think about it: an article about people not understanding focal length….. followed by feedbacks, ONLY BY PEOPLE WITH NO UNERSTANDING OF FOCAL LENGTH, TELLING YOU THAT YOU ARE WRONG!
Admit it: that is funny! Made me laugh.
Anyway, thanks for a great site, and thanks for sharing.
Best.
Jan
Which is why I’ve decided not to reply