Is this correct?

[AB26]

The lens does nothing to perspective. Only the distance.

Urban,
If the lens cannot distort perspective, what has distorted perspective in this image? It surely is not distance.




Whatever you do you cannot restore the altered, changed, misrepresented, distorted, perspective in this image. You can zoom in zoom out, get your nose right up against the screen, stand a mile away from the screen, perspective in this image will still be distorted. The only way of correcting perspective in this image is if I go back and re-shoot the same subject with a different FOCAL LENGTH lens.

Does that make sense or not?

Don’t we talk of some lenses as lenses giving a more realistic perspective than others?

[ajohnw]

I haven't read all of the posts but to me there seems to be confusion about 2 different things Andre. Perspective as per the wiki and perspective due to position angular and otherwise of the lens and the subject. Totally different subjects. One relates to things like keystone, the other and I feel more important one relates to a lens's view on a sensor and the view via the human eye. There are others pincushion and none linear magnification across an image after a fashion as it may introduce keystone type effects. Barrel may not be seen as a perspective but a fish eye for instance gives a fishe's eye perspective that can be converted to other perspectives or left as it is. The same thing can be done to keystone, images of the pages of a book that are not flat and etc.

A problem as some see it with the English language is that words often have context sensitive meanings. For instance I have just posted my perspective on this area in this post and am now doing the same thing again in this paragraph. Not that the various possible meaning of words bothers me at all. Oh dear I have done it again.

Some people might find this rather confusing especially relating to perspective in a photographic sense. They might even decide to tilt there monitor to correct keystone.

John
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[Inkanyezi]

Urban,
If the lens cannot distort perspective, what has distorted perspective in this image? It surely is not distance.

I don't have the slightest idea why you think perspective is distorted in the image. As it is a flower, it is impossible to know whether you think the flower itself is distorted or if you just think it is the background in relation to the flower. The image is taken at fairly close distance with a narrow angle lens. Hence it can be expected that, not knowing the size of the particular flower or the distance, the image might show the flower enlarged, larger than life size, on the screen.

Due to the narrow angle - as we posed as "framing" - perspective might be perceived as "compressed", when looking at the image from a closer distance than the one which will render the same viewing angle as the camera at the actual occasion. Thus buds in the background may appear to be closer than perceived when looking at the scene without taking the picture. However, it does represent what the camera sees, and if you would have looked at it from the position of the entrance pupil of the lens, perspective would have been just as in the image.

So your question is incomprehensible to me. The image is not distorted. Perspective is not distorted.

Whatever you do you cannot restore the altered, changed, misrepresented, distorted, perspective in this image. You can zoom in zoom out, get your nose right up against the screen, stand a mile away from the screen, perspective in this image will still be distorted. The only way of correcting perspective in this image is if I go back and re-shoot the same subject with a different FOCAL LENGTH lens.

Does that make sense or not?

It doesn't make sense, as perspective is not distorted in the image. You might certainly get another image if you use another focal length and the same framing, as then you would have altered the distance to the subject. The lens does not distort, neither does distance, but a disparity in viewing angle for the image and angle of view of the camera when taking the picture, can cause perspective to look odd. In this case it might be perceived as "compressed" as the angle of view of the camera is narrow, and we look at it with a wider angle of view.

However, mostly we would look at a single flower with a narrow viewing angle, so what might be the issue here is the busy background, which could be changed in various ways. You could get more bokeh, by using a larger aperture, or you might alter the height of the camera, to get a less busy background. Of course you could also move in closer with a shorter focal length, which would make the more distant flowers and buds smaller in the image, due to the change of perspective that results from the closer distance.

Don’t we talk of some lenses as lenses giving a more realistic perspective than others?

No we don't. Up until now, there has been talk about distortion of perspective, but we could change focus to the subject of lenses giving more or less realistic perspectives.

The "realistic" perspective is acquired, when an image you look at will present the same perspective as you would expect by looking at the scene IRL. Hence when we take a portrait, we enlarge it to a certain size, and when we look at it from a distance that renders our angle of view upon the image equal to the angle of view of the camera, we perceive that the perspective is normal. Hence a "portrait" lens is often a particular focal length, which gives that "natural perspective" when looking at the picture. For a crop camera this focal length might be somewhere about fifty to seventy millimetres. Then the portrait is taken from about one and a half metres distance, and the image made in a size suitable for the most common viewing distance. If you will put it on the wall, that size might be 18*24 or 24*30 centimetres, and if you put it on top of some furniture or as a mantelpiece, maybe you make it 13*18 centimetres. Or you could make a smaller image for your wallet, or put it in an album in the size of 9*12 centimetres.

In most cases when looking at those images, they will take up a smaller angle of view than the angle of view of the lens when the picture was taken, but it is always possible to move in a bit closer, which can render the same angle. We have got used to portraits looking like that, and it is called a "natural" perspective, the one we find good looking. When confronted (affronted?) with a portrait taken from about 30 cm distance with a wide angle lens, we might think that the perspective is distorted, although it is exactly what you would see if you looked at the person from that distance. To perceive the perspective of a wide angle shot having a "natural" perspective, you must also move in when looking at the image, so that you see it from a close distance, which permits your viewing angle to be the same as the angle of view of the lens. Mostly we don't find such close-up portraits flattering. That's why we prefer portraits taken from a distance of one and a half to two metres. That is the distance we mostly see people, as for example when having a cup of tea at a table.

This reasoning was also behind the choice of "normal" lenses, and also back then there was disagreement. Some thought the "normal" lens should be the same focal length as the diagonal of the frame, while others opted for a longer focal length. For the 24*36 mm frame, the diagonal is 43 mm, but most cameras had a 50 mm "normal" lens. It was regarded as providing a "natural" perspective.

Still perspective depends on where the entrance pupil is located related to the subject, and any perceived "distortion" of perspective is a mismatch in viewing distance regarding the angle of view of the camera for that particular image.

[ajohnw]

Really the reason for variations as far as focal length and the same framing go is all down to magnification which varies according to the focal length of the lens. This aspect might clear things up for some. The wiki doesn't really show the right shots to illustrate the effect when it's used for effect but a search for the term telecompression came up with one that does a much better job of it. It even shows an extreme example 1st to point out the differences to look for before stepping through various sizes.

http://www.slrlounge.com/school/lens-compression/

The wiki does show a good example of telecompression towards the end. They have made some effort to keep the SUBJECT framing the same but over a rather limited range of lenses.

This area is an effective compositional effect when used on suitable subjects. It alters the apparent depth of images and can even introduce either wanted or unwanted distortions. Curing the latter often involves finishing up with a smaller image, interesting aspect after a fashion as the framing is then different.. In portraiture the effect can and is used to have some control of the subjects features. I used to have some interesting photographs of myself taken by some one else that illustrated this rather well. One was a passport photo taken with a 645, couple of spare frames left on the roll from a job. I then had the passport signed. The person who did that came back with a quizzical look on their face and asked me if it was actually me. Even am I sure. My friend had an evil sense of humour. He used his longest lens and stuck a teleconverter on. I have a fairly prominent nose. Fortunately longest lenses on cameras of that size generally aren't that long. This actually caused people in customs to spend more time studying me and the photo than usual. Noticeably so.. Shooting distance - I would say getting on for 6m and the usual portrait framing. Actually as he had customers asking for free passport photo's not realising the work involved he bought a polaroid passport camera that offered limited control of this sort of thing to keep them happy. They would expect him to do better job than a photobooth or the shop round the corner, Taking portraits of people who just happens to walk through the door wanting one is much tougher than picking out naturally attractive subjects but the same technique is used on them at times just for effect.

Really people have 2 options. Worry about what things look like when viewed from certain distances or make use of what can be a useful compositional factor.

The other thing mentioned around the web and other places is the so called standard lens and it's relationship to the eye. These have roughly the same focal length as the diagonal of the format. In principle these cover the field of view of the eye - where vision is critical excluding peripheral effects.

John
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[William W]

Happy Birthday

[William W]

. . When confronted (affronted?) with a portrait taken from about 30 cm distance with a wide angle lens, we might think that the perspective is distorted, although it is exactly what you would see if you looked at the person from that distance. . .

Puts that topic of discussion to bed nicely.

WW

[ajohnw]

Puts that topic of discussion to bed nicely.

WW

Really Bill. Just to clean things up more.


Lens perspective



Which one has the correct proportions? None of them actually. I left the nose shadow in as it tends to show something else and removing it something else as well but quick job. All framed and cropped as close as I could reasonably do it. Can I get eye views like this? Perhaps people had better try it.

I should add that there is some creative barrel and pincushion distortion going on as well.


Magnification via cropping, same shot. The people make a useful length measuring stick.





John
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[ajohnw]

Might be best to take away the mention of barrel etc. Same lens, same setting and more attempt to keep in line rather than drifting off. Angle changed, not as much as some might think. These are top to bottom crops, Some framing errors but not a lot. Lighting changed a bit.



John
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[natalyanders]

I cannot directly compare myself without serious effort because one of my cameras is film (I have a 35mm Canon AE-1, and a Fuji X-A1), and I would have to burn the rest of the film and have it developed.
I happen to have a 50mm lens I use for portraits on the X-A1, and I have a 50mm lens that I am starting to use for portraits on the 35mm film.
My question is, if I shoot a portrait from the same spot with both 50mm lenses, will the faces look the exact same? I realize that I may see more overall in the frame, but will they have the same proportions and be just as flattering as each other?
I realize that I may have to step in closer with the 35mm to get the face to fill the frame the same way, changing my perspective, but I am asking what if I don’t do that… In the end, I want to know if my 35mm camera will produce portraits that are less flattering than my Fuji?
I found some helpful tutorial here and here.

[chauncey]

If I read you correctly, you're comparing two different 50 mm lenses that you want to use on that
film camera, but...you don't give us any lens info. All 50 mm lenses are not created equally.
http://kenrockwell.com/canon/compari...0mm-lenses.htm ...note the price differences.

[Manfred M]

Welcome to CiC Nataly.

No, the two lenses will not give you identical results. The Fujifilm camera has an APS-C sensor and I believe it has a 1.5x crop factor.

Now if you use a 50mm lens on the Fuji, you will be getting the equivalent of a 75mm lens on your 35mm Canon film camera (1.5 x 50 = 75mm), so that will give you a short telephoto look and a more flattering image, although you will have to stand back a bit further to get the same framing.

I personally tend to not use a 50mm lens for portraits on 35mm / full-frame cameras. I find that a 50mm lens is a bit short for my liking even on a crop-frame APS-C camera, but that is just my personal shooting style. My full-frame portait lens is a f/2 105mm (or the f/2.8 70 - 200mm zoom) and on my film cameras I use a slightly longer f/2.8 135mm lens.

[William W]

. . . My question is, if I shoot a portrait from the same spot with both 50mm lenses, will the faces look the exact same? I realize that I may see more overall in the frame, but will they have the same proportions and be just as flattering as each other?


I realize that I may have to step in closer with the 35mm to get the face to fill the frame the same way, changing my perspective, but I am asking what if I don’t do that

*

My question is, if I shoot a portrait from the same spot with both 50mm lenses, will the faces look the exact same?

Simple answer, if you take both photos from exactly the same Viewpoint (the same spot) Yes the face will look the same in each.

WW