Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,765   Posts: 1,516,354   Online: 1005
      
Page 9 of 9 FirstFirst ... 3456789
Results 81 to 86 of 86
  1. #81

    Join Date
    Feb 2010
    Location
    Montreal, Canada
    Shooter
    Multi Format
    Posts
    4,494
    I'm probably way off here as I don't do any portrait photography, but when taking the portrait isn't it the distance between camera and subject that dictates the perspective rendering, and then the choice of lens is essentially a framing/cropping choice? Ignoring optical aberrations, for a fixed film to subject distance, changing focal lengths does not change perspective, only cropping. If film had infinite resolution and no grain, all you'd need is one short focal length rectilinear lens and you could just crop under the enlarger.

  2. #82
    markbarendt's Avatar
    Join Date
    May 2008
    Location
    Ignacio, CO, USA
    Shooter
    Multi Format
    Posts
    5,583
    Blog Entries
    3
    Images
    19
    Quote Originally Posted by Michael R 1974 View Post
    I'm probably way off here as I don't do any portrait photography, but when taking the portrait isn't it the distance between camera and subject that dictates the perspective rendering, and then the choice of lens is essentially a framing/cropping choice? Ignoring optical aberrations, for a fixed film to subject distance, changing focal lengths does not change perspective, only cropping. If film had infinite resolution and no grain, all you'd need is one short focal length rectilinear lens and you could just crop under the enlarger.
    Yes, distance to subject sets up the angular relationships to the camera.

    So, if the distance to the subject is the same, say 6', and the subject is printed the same size in separate prints, then both prints should have the same perspective.

    The print sizes would be radically different if un-cropped.

    If both prints were viewed from 6' then they both would look "normal". If viewed from 3' they both would exhibit "flattening". Viewed from 12' both would bulge in the middle. (Albeit, the small print from the long lens wouldn't normally be viewed at that distance.)
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  3. #83

    Join Date
    Aug 2006
    Shooter
    Multi Format
    Posts
    314
    Quote Originally Posted by Michael R 1974 View Post
    I'm probably way off here as I don't do any portrait photography, but when taking the portrait isn't it the distance between camera and subject that dictates the perspective rendering, and then the choice of lens is essentially a framing/cropping choice?
    You're not way off, you're exactly right as far as it goes. People still need to see the result. (You might realize that if you could put your eye up to the camera lens and see the image inside, this is the ideal viewing condition.)

    Print size and viewing distance are near as simple - the difficulty is trying to explain it to people. I think you'll get it simply from looking at the attached drawing (I hope I can attach it). Maybe you can help explain how it works.
    Click image for larger version. 

Name:	PC163619.JPG 
Views:	20 
Size:	261.0 KB 
ID:	61409
    Background on the drawing - It's from the book Freehand Drawing, Self-Taught, by Arthur Guptill in 1933. The "tracing on glass" routine is a preliminary exercise for the drawing student to become acquanted with proper perspective. The dashed lines can be taken to show a camera's field of view to a subject, the sheet of glass can be taken to represent a print showing proper perspective.

    ps; reason for THIS book: it belonged to my father; a couple years ago I came across it and was looking through it. Some text and drawings looked familiar, and as I thought about it, I partially recalled and realized that THIS was the book that helped me, as a schoolboy, get my first understanding of perspective (I needed to know this to draw army tanks and jet airplanes shooting at each other). This particular sketch is as good as anything I've seen in getting across the idea of proper perspective in photographic prints.
    Last edited by Mr Bill; 12-18-2012 at 12:55 AM. Click to view previous post history.

  4. #84

    Join Date
    Feb 2009
    Shooter
    Large Format
    Posts
    654
    Regarding post #82

    Yes, distance to subject sets up the angular relationships to the camera.

    So, if the distance to the subject is the same, say 6', and the subject is printed the same size in separate prints, then both prints should have the same perspective.

    The print sizes would be radically different if un-cropped.
    In the 1980s the US photo magazine Modern Photography published at least one article showing 35mm SLR photos of the same scene shot from the same camera position through three different lenses: normal, wide angle, and telephoto.

    The normal and wide angle shots were then cropped so that the same areas at the same size were printed side by side in each shot. The only differences were in apparent grain due to the differences in magnification to make the selected areas of the normal and wide angle shots the same size as the telephoto shot. There was no difference in the apparent perspective. It was a convincing demonstration of the fact that scene perspective is controlled by lens-to-subject (or eye-to-subject) distance and no other factor.
    Last edited by Ian C; 12-18-2012 at 09:10 AM. Click to view previous post history.

  5. #85

    Join Date
    Feb 2010
    Location
    Montreal, Canada
    Shooter
    Multi Format
    Posts
    4,494
    Exactly what I was trying to say in post #81!

  6. #86
    markbarendt's Avatar
    Join Date
    May 2008
    Location
    Ignacio, CO, USA
    Shooter
    Multi Format
    Posts
    5,583
    Blog Entries
    3
    Images
    19
    Quote Originally Posted by Michael R 1974 View Post
    Exactly what I was trying to say in post #81!
    That part of the equation is exactly right.
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

Page 9 of 9 FirstFirst ... 3456789


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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