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View Full Version : 3-Dimensionality - which wins and why!


Robert_Lay
26th of July 2007 (Thu), 16:08
Which of these two pictures would you say best provides the illusion of 3-dimensionality and why?

airfrogusmc
26th of July 2007 (Thu), 16:43
The bottom because there is depth in the image. Things are close and farther away from the camera giving the illusion of depth. The first image is very 2 demensional becuase all the subects apear to be om the same plane. A long lens can help with the later where as a wide angle lens can help add depth when things are closer and farther from the camera.

Robert_Lay
26th of July 2007 (Thu), 18:14
The bottom because there is depth in the image. Things are close and farther away from the camera giving the illusion of depth. The first image is very 2 demensional becuase all the subects apear to be om the same plane. A long lens can help with the later where as a wide angle lens can help add depth when things are closer and farther from the camera.

I would say that I would agree with you in regard to which gives the better illusion of depth.

Now, can you give an explanation of what perspective or vantage point issues there are that account for this illusion?

Mayavi
26th of July 2007 (Thu), 18:19
Its the cement bench on which the family is sitting in the second picture. All lines in the second pic are at an angle while the road, rail etc are horizontal in the first.
But then both would have looked same to me if you didn't mention the word 3-D in the first post :-S

airfrogusmc
26th of July 2007 (Thu), 18:55
Laying objects also can help create debth which is going on in the second image and a wide angle lens helps in that regard. In the frst most of the people are claose to the same depth and thats even more pronounced by the compacting of space of the long lens but the most important which I think you are really getting at is subject distance from the camera. The people sitting are fairly close thus creating a real since of depth. In the other image the camera is at a much greater distance from the first subjects.

Robert_Lay
26th of July 2007 (Thu), 22:20
So, it seems that most observers have no great difficulty in realizing and appreciating the illusion of 3-dimensionality. Furthermore, I think most people would agree that the photographer has certain choices or strategies available that can be used to give the scene more depth and reality.

My thanks to all who contributed.

oldradioman
26th of July 2007 (Thu), 22:48
Hi Bob,

Very interesting!! I have to agree that the second one gives much more feeling of depth.

I have a question. What would be the affect if the camera was about one foot or so lower but so low as to cut off the “Carl’s” sign? I am trying to learn more about landscape photography and quite often I see comments about being low to better display depth.

Thanks and 73
Arvid

Glenn NK
26th of July 2007 (Thu), 23:27
As Holmes would say to Watson, "it's quite elementary my dear Watson"

It's the relative size of the people; nearer ones appear larger, farther ones appear smaller.

Good landscape photographers/artists know this instinctively.

That's what gives perspective.

Robert_Lay
27th of July 2007 (Fri), 09:31
Hi Bob,

Very interesting!! I have to agree that the second one gives much more feeling of depth.

I have a question. What would be the affect if the camera was about one foot or so lower but so low as to cut off the “Carl’s” sign? I am trying to learn more about landscape photography and quite often I see comments about being low to better display depth.

Thanks and 73
Arvid
Hi Arvid,

OK - You are asking whether or not it would increase the illusion of depth or 3-dimensionality to lower the camera, and you have also framed the question so that it implies that the camera will not be tilted in the process (you have stated that the Carl's sign will not be decapitated).

My answer is that you are more likely to lose depth with such a vantage point, but it is really hard to say since there are so many things that will change with such a perspective.

Let me throw in a few more issues that no one has yet mentioned, although Mayavi is almost there in his comments.

He mentions that there are several lines in the bottom picture that are at different angles. In fact, the lines in that picture create a vanishing point to the left and another vanishing point to the right. Whenever there are lines that are parallel in fact but appear to converge to a point at infinity, then the illusion of 3-dimensions is greatly enhanced.

So, if Arvid had suggested tilting the camera so as to create yet another vanishing point as the verticals converged, that would probably enhance the illusion.

Glenn NK
28th of July 2007 (Sat), 02:56
My $0.02 worth in 2007 dollars for what it's worth (even fifty years ago, 2 cents wouldn't buy much more than a jaw-breaker or three).

Books by pro landscape photogs generally recommend putting the camera at typical eye level to capture an image that a human of "average" height would see as we are so accustomed to seeing landscapes from our vantage point that other vantage point heights don't "compute" with our brain experience. From what I've read and experienced, good landscapes use "size cues"; objects that we are familiar with that vary in size, getting smaller (and less in focus) with distance.

In architectural rendering, one vanishing point is used at times, and at other times two are used. When two are used, they can be placed at the extreme left and right edges of the drawing, or even off the drawing. Two are very effective at portraying a building, but it's really not what the eye/camera sees, which is really a single VP on the axis of the lens/line of vision. Wherever we or the camera looks, that is where the VP is, but once the image is rendered on a two dimensional medium, the VP is stationery and can't be moved about.

The double VP is very dramatic looking, but can be difficult to actually draw - particularly prior to CAD - I've drawn more than a few, and they can be nasty - there are no horizontal lines in a two VP perspective drawing - vertical lines remain vertical. If the VPs are raised above midheight of the paper, the building appears to be viewed from above; if the VPs are lowered, the building seems to tower above us.

A neat trick that will give a realistic perspective is to photograph the building, project it onto a piece of paper and trace the outlines; a slick trick shown to me by a talented draftsman.:cool:

Accept my apologies if this is too far off topic.

Robert_Lay
28th of July 2007 (Sat), 08:11
Excellent!
Thanks for sharing, Glenn. Very helpful for gaining a better understanding of perspective and how it helps to create the illusion of depth.
Thanks!

airfrogusmc
28th of July 2007 (Sat), 08:58
Glenn thats interesting but probably one of the greatest landscape photographers (Ansel Adams) built a platform on top of hs car so he could get up higher. A good deal of his famous photographs were taken from that platform.

Glenn NK
28th of July 2007 (Sat), 13:33
Robert:

For what little I've added, I'm glad to share. I have my own personal copy of Tim Fitzharris's book on Landscape photography. I've borrowed a few from the public library, but although not bad, they "don't hold a candle" to Fitzharris's book. It's essential for landscape photogs:

http://www.amazon.com/s?ie=UTF8&search-type=ss&index=books&field-author=Tim%20Fitzharris&page=1

I read his book in its entirety in March, and in the past few weeks have been picking out chapters to re-read. At first read it was quite informative, but every time I look again, I learn something new. Quite simply, if anyone is serious about this subject, his book is the book of reference. He deals extensively with perspective and the illusion of depth. He even offers a simple technique to avoid using hyperfocal distances in the field; I've quoted it on other threads - as an owner of three zooms, I'm quite aware that they don't have DOF marks. Incidentally he uses zooms for most of his landscape work.

The chapter on "Expressing Perspective" contains a wealth of information; in addition to the height of camera already mentioned, he discusses "Controlling Overlap".

Another useful perspective tool that needs skillful handling is overlapping. Precise lateral and vertical placement is usually needed for this strategy to work effectively, especially when utilized with smaller landscape features such as trees or rock. Such elements are often so similar that they blend together in a muddle not readily distinguished by the viewer. To avoid confusion, try to overlap only simple areas of contrasting colour, line direction, brightness or shape (horizontal limbs crossing vertical trunks for example.


The technique of Ansel Adams (setting up higher) could, I think, be useful with the gigantic landscapes of the Grand Canyon where everything is "much larger than life".

Fitzharris on Angling for Depth; For a maximum three-dimensional effect, set up at about a 45 degree angle (above the horizontal) on the first size cue in the composition. Use a focal length wide enough to include at least the horizon and a bit of sky. If you place the camera too low, you will lose visual exposure of the spaces between the size cues; if set up too high you will lose the horizon and the familiar eye-level configuration of the size cue. Translation: the flowers in the immediate foreground would be positioned 45 degrees down from the horizontal axis of view; and they should be in focus. For a 1.6 crop, shooting wider than f/11 with any focal length longer than about 25 mm - won't provide adequate DOF.

One thing often forgotten in our excitement when viewing a beautiful scene, is to move about for the best vantage point - not necessarily getting a unique point, but aligning all the features of the terrain so that they work together - difficult to explain without a lengthy dissertation.:) Fitzharris refers to "size cues"; elements which give us a sense of scale, hence distance. The most obvious example are waves on water which get smaller in appearance with distance.

Enough of this ranting - as you can see, I'm a bit passionate about it - now I just need to stop shooting flowers and get on with the larger world. To this end, my wife and I are renting a motorhome for August and travelling to the land of our births, and passing through the Rocky Mountains of BC and Alberta, then to the plains of Alberta and Saskatchewan.

oldradioman
28th of July 2007 (Sat), 16:36
Thank you, Glenn. I just ordered that book from the library.
Have a great time on your trip and, this goes without saying, take lots of pictures.

Arvid

Robert_Lay
28th of July 2007 (Sat), 17:53
...
I have my own personal copy of Tim Fitzharris's book on Landscape photography. I've borrowed a few from the public library, but although not bad, they "don't hold a candle" to Fitzharris's book. It's essential for landscape photogs:

http://www.amazon.com/s?ie=UTF8&search-type=ss&index=books&field-author=Tim%20Fitzharris&page=1


I'm taking your hint to heart and trying to find access to a copy.
Much appreciated!

Bon voyage, and bring back lots of pictures.

Glenn NK
28th of July 2007 (Sat), 21:11
Thanks guys, and I really don't think you'll be disappointed with Fitzharris's book.

At first I read it, and thought, "well that wasn't too hard - I've learned a few tricks". Then I started re-reading - wow - it's changed my approach to landscape photography. For example, I no longer point the camera and say, "might as well take a shot". Now I think and say, "that's a waste of a shutter actuation".:lol:

Of course I've learned many things on this site; I'm gearing up to do some HDR by getting some extendable points for my tripod so I can anchor it firmly in the ground to prevent camera movement between shots.

I know I've learned a few things from Mr. Lay in the past few months.

airfrogusmc
29th of July 2007 (Sun), 03:01
Glenn, maybe take the next step and get a viewcamera? :D:D

Glenn NK
29th of July 2007 (Sun), 12:17
Glenn, maybe take the next step and get a viewcamera? :D:D

If money wan't part of the equation, I'd be on a Hasselblad forum.:cool:

airfrogusmc
29th of July 2007 (Sun), 13:51
Blads are great I've owned em and miss mine now that I don't have one. Really nice for portraits...

4X5 in my opinion is the way to go if you are serious about landscape like you seem to be. Zone system, large format B&W negs just can't be beat and the tilt and shift control of the camera is an almost must. You certainly seem to have a real passion for it so I wouldn't be surprised if someday I see you with a zone 6 or maybe and old deardorf. Maybe even 8X10? ;)

midnitejam
29th of July 2007 (Sun), 19:15
I would say that I would agree with you in regard to which gives the better illusion of depth.

Now, can you give an explanation of what perspective or vantage point issues there are that account for this illusion?

Bob, in the 1st pic, there is no "anchor". The 2nd shot has an anchor in the lower right-corner and the biggest part of the anchor is facing into the image.

Robert_Lay
29th of July 2007 (Sun), 22:24
Bob, in the 1st pic, there is no "anchor". The 2nd shot has an anchor in the lower right-corner and the biggest part of the anchor is facing into the image.

Dear midnitejam,

Thanks for participating. Interesting terminology - "anchor".
Did you also notice that the people standing in close in the foreground seem to be almost twice as tall as the ones back closer to the building? I think people are almost always an asset to an image - even when it's a landscape and the people aren't the main subject.

Cathpah
30th of July 2007 (Mon), 12:54
i would say definitely the second image.

there is a foreground, midground, and background. that alone solves the which has more depth question.