What is telephoto compression (perspective compression)? Tom Axford 2023

Yes, and once the tingling in your toes wears off, lets not ignore the fact that the expression, "Zoom with your feet" is figurative and probably never was meant to fit any rigorous definition of whatever "Zooming-in" actually means.

(IMHO) Most people view the purpose of a zoom lens to magnify the central subject in the frame, to make it bigger or smaller, ignoring any of the issues addressed above. To them, moving closer or further from the subject is also for the specific purpose of making it appear larger or smaller.

That image magnification is pretty much the only thing they are after or that they notice in the resulting image. Simplistic, inaccurate, and good enough, most of the time. That's important. It's folly to ignore or diminish that simplistic understanding. It's not wrong. It's not a complete understanding, but it is useful.

Rich

My guess is that also for many readers that last point will be new, it was for me when I first read a post from you on the old site. Maybe expanding a bit on it (‘tell what you are going to tell, tell it and then summarize it’ as someone once told me) could work, you could adapt the reply above. And anamorphosis might find a place there as well.

Bruce Percy has a pretty good take on composing, I think. Set your focal length to achieve the size of background you desire (eg a mountain), then use your feet to achieve the size of foreground you want (eg a rock, bush - without walking off a cliff).

We've all seen Wyle E. Cyote run off the cliff many times I never ends well.

Speaking about beginners, I still need to see one here.

Oh man, all this techie stuff hurts.

So zoom with your feet. Tried that once and jumped when taking a bird in flight shot ...... It didn't work!

So me being really basic and all. The seagull is not close to the Cormorant.

800 F/5.6.

Danny.

Yes, it is rather strange because I suspect that early photographers using large format glass plate cameras probably knew much more about perspective than most modern photographers. I have an old "Manual of Photography" (7th edition, 1978) that was first published as the "Ilford Manual of Photography" in 1890. It has a chapter on "The geometry of image formation" that covers lenses, depth of field, etc., but also includes a large section on perspective. There are several pages on "perspective when viewing the photograph". Those things are largely omitted by most modern tutorials on photography.

I think I can still go back and edit my first post to add more to it. I'm reluctant to do that without careful consideration - I don't want to make it worse! However, I will think about that. I'll try to find some good example images too.

So basically, both birds are a long way away. The seagull is even further away. But the gap between them is very small compared to the gap to the camera. So the reduction in apparent size of the seagull from that little bit of extra distance is very small compared to the reduction in size of the pair of birds. The brain can't make easy sense of that and it makes us think they are at the same distance. We notice it because the magnification brings the subject close to us and the compression easy to recognise. Exactly the same effects apply to wide angle lenses, but the subjects are rendered so small we can't even see them, so we overlook the effect.

Why then does everyone still call it telephoto compression? (Not that it makes much practical difference to photographers. We see the compression effect when we use teles, we don't when we use wides, so it might as well be caused by the focal length for all practical purposes).

I have edited my OP to include some example images and further explanation.

I hope this is helpful.

In simple terms (I like that) yes and we see it alot with tele lenses. Scale vs distance vs view and often angle. I don't use anything under 500mm except my phone camera. So wide angle on birds and motorsports I wouldn't know. Motorsports it happens a lot as well.

Danny.

An example of background de-compression:

www.flickr.com/photos/nasahqphoto/27042062719/

Consider a photo of a person's head. The tip of their nose might be 6 inches closet to you than their ears.

If their nose is 1 foot from the camera, than the ears are 1.5 feet away. The ears are 50% further away from the camera than the tip of their nose.

If their nose is 10 feet from the camera, than the ears are 10.5 feet away. The ears are only 5% further away from the camera than the tip of their nose.

Assuming you are using different focal lengths to keep the face the same size in the frame, the image where the ears are 50% further away will look when the ears are 10% further away.

Many people think a face looks better when it isn't too close to the camera.

Yes. But you can do this with a wide angle lens. I have done so as an exercise. Take a portrait of someone with a 17mm lens on full frame. Make the subject stand 30 feet away. Crop the resulting image to a close up. Voila, no sign of big nose effect! Of course, the resolution collapses if you do this so it's pointless in practice.

I have found photographers steeped in the lore of photo magazines and internet articles who often find this difficult to believe. They are convinced it can only be done with a tele lens. "But....but...only tele lenses can compress perspective" they say.

That is due to a change in perspective brought about by changing the subject distance.

It's not the same as perspective compression due to magnifying the view while keeping the subject distance fixed.

Perspective is a multi-faceted topic.

I have added another paragraph at the end of my OP.

It's in beginners questions so it might have been started by one looking for an answer.

A great visual demonstration of shifting perspective and focal length while keeping the subject the same size in the composition is the famous dolly zoom effect used in cinematography.

Yes indeed, dolly zoom changes the subject distance while zooming at the same time. The camera's perspective changes at the same time as the viewer's perspective. It is a combination of two effects.