Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,934   Posts: 1,585,598   Online: 735
      
Page 12 of 12 FirstFirst ... 26789101112
Results 111 to 119 of 119
  1. #111
    Alex Hawley's Avatar
    Join Date
    Jul 2003
    Location
    Kansas, USA
    Shooter
    Large Format
    Posts
    2,895
    Images
    63
    David, Ron, you're both right. This was done with natural sunlight where the sun was very high and to the right, strongly backlit but with just a small amount of front lighting. And this is the crux of my point - getting the 3-D effect is not dependent on the paper, lens, film or any of that stuff.
    Semper Fi & God Bless America
    My Photography Blog

  2. #112

    Join Date
    Nov 2004
    Location
    Bilthoven, The Netherlands
    Shooter
    4x5 Format
    Posts
    1,858
    Quote Originally Posted by Alex Hawley View Post
    I used to generally agree with all that has been said above about Azo, contact printing and so forth until I took this one. The scan is from the test shot I did on Polaroid Type 664. Please don't try to judge the 3-D effect by this crummy scan, but believe me, on the actual Polaroid print, its there. I also did the full frame 4x5 shot on both Ilford FP4 and Efke 25. Not only that, but I also shot both films with two different lenses; my 12 inch 1940's vintage Commercial Ektar and a much newer Schneider 12 inch Xenar. I see the 3-D effect on all of the prints; polaroid, 4x5 contact, 8x10 enlargement, and 11x14 enlargement, all made on Kodak and Ilford multi-grade papers. So I dunno, the mileage varies greatly, but can be obtained seemingly irregardless of the materials in the mix. For me, that throws it all back to the lighting, contrast, and subject.
    In the example you are showing, the 3-D effect is created by the shadows. If your lighting is OK, and in the exampele it is OK, you can use any photographic procedure. [ in computer games this kind of 3-D is being used]. In the case of landscapes, 3-D has a different origin ( the physics behind it is different), and therefore that will be another story.

    Jed
    Last edited by Jed Freudenthal; 01-19-2008 at 03:19 PM. Click to view previous post history.

  3. #113
    gainer's Avatar
    Join Date
    Sep 2002
    Posts
    3,726
    Images
    2
    The reason I asked about the lens opening is that it is possible for a lens that is wider than the subject to see part of it that cannot be seen from a single point. A little ray tracing will show what I mean. I have only done the imaginary ray tracing, but you can imagine a ray that is tangential to a small round object entering the edge of the lens aperture. It will come from behind the surface you could see from the center of the lens. Such happens with binocular vision when the interocular distance is greater than the width of the object. Each eye sees part of the object that the other cannot see. The brain integrates the two images. It's just a thought.
    Gadget Gainer

  4. #114
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    23,558
    Images
    65
    Quote Originally Posted by gainer View Post
    The reason I asked about the lens opening is that it is possible for a lens that is wider than the subject to see part of it that cannot be seen from a single point. A little ray tracing will show what I mean. I have only done the imaginary ray tracing, but you can imagine a ray that is tangential to a small round object entering the edge of the lens aperture. It will come from behind the surface you could see from the center of the lens. Such happens with binocular vision when the interocular distance is greater than the width of the object. Each eye sees part of the object that the other cannot see. The brain integrates the two images. It's just a thought.
    Printed on a flat surface though, this type of imaging has (to my eye) been somewhat distorted. Like using a wide angle lens without barrel distortion in a way.

    PE

  5. #115
    gainer's Avatar
    Join Date
    Sep 2002
    Posts
    3,726
    Images
    2
    Any backlighting would be emphasized by a wide lens opening. It would show at edges as a bright outline.
    Gadget Gainer

  6. #116

    Join Date
    Nov 2004
    Location
    Bilthoven, The Netherlands
    Shooter
    4x5 Format
    Posts
    1,858
    Quote Originally Posted by Photo Engineer View Post
    Printed on a flat surface though, this type of imaging has (to my eye) been somewhat distorted. Like using a wide angle lens without barrel distortion in a way.

    PE
    You are right; this type of imaging on a flat surface is a distorted image. The distortion is described with methods used in projective geometry. It has no relation with 3-D effects with subjects nearby. That is determined by the shadows. Students in photography academies had to light and photograph an egg, to learn the tricks that an egg looks like an egg.
    3-D in a landscape is different. The natural light is different, because of scattering, the limatation of the quality of the human eye plays a role, etc.

    Jed

  7. #117
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    23,558
    Images
    65
    Quote Originally Posted by Alex Hawley View Post
    David, Ron, you're both right. This was done with natural sunlight where the sun was very high and to the right, strongly backlit but with just a small amount of front lighting. And this is the crux of my point - getting the 3-D effect is not dependent on the paper, lens, film or any of that stuff.
    Alex, Jed;

    My experience would make me agree with both of your comments.

    Alex, I would alter your words above slightly as follows "the 3-D effect is not entirely dependent on the paper, lens, film....." as I feel that there are other effects such as I described from Kriss' work and the subjective factors that have been discussed here. Of course your "any of that stuff" takes it in, but the word "entirely" takes the onus off of any one factor and leaves the solution up in the air, as it really must remain. Just a thought. Many good points to ponder though.

    PE

  8. #118
    gainer's Avatar
    Join Date
    Sep 2002
    Posts
    3,726
    Images
    2
    I will have to do the experiment. It seems simple. Photograph something narrow, like the stem, with backlighting and see if the lighting wraps around more with a large aperture than with a small. I can get apertures from 1.1" down with my Canon Elan IIe with auto exposure. We will see if the backlighting is preferentially modified by the aperture.

    The subject is not flat. You won't get any depth cues copying a flat painting or another photo.

    It is interesting to note that hyperfocal distance and angle of acceptance are dependant on pupil diameter, while exposure is dependant on relative aperture. I am referring here to the angle of the cone of light emanating from a point in the scene that enters the pupil. If you want your 35 mm camera to have the same hyperfocal distance as an 8x10 viewer with 305 mm lens set at f/64 it's 50 mm lens will be set at f/10.5. At any setting of the 305 the 50 will have a much shorter exposure for the same depth of field and the same angle of acceptance. At the same exposure time, the 305 will have a larger acceptance angle. I am hypothesizing that the scale effect on perceived depth in a flat photo is due to fact that a large pupil sees more of the sides of things, and that exposures tend to be reckoned so that relative apertures are likely to be the same whether one uses a huge camera or a small one. However small the acceptance angle may be, the tangent of that angle for a 24 inch lens is 3 times that for an 8 inch lens at the same f-stop.
    Gadget Gainer

  9. #119

    Join Date
    May 2007
    Location
    Tucson Az
    Shooter
    Multi Format
    Posts
    226
    I have seen the 3d effect in the proliferative work of Bret Weston, Michael Smith, and especially Paula Chamlee. I have seen it in numerous silver bromide prints as well.

    I don't think this is a property confined strictly to azo. I think its a property of any well crafted print.

    Yours;

Page 12 of 12 FirstFirst ... 26789101112


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin