large format Camera movementsgreenspun.com : LUSENET : Large format photography : One Thread
I am having trouble writing an essay on the large format camera as part of my Btec Nd photography course. I was hoping that you could help me?
I need to know more about shift, swing and tilt movements and the implications of schiemphflug and camera yaw.
If you could help me out this would be of a great help.
-- Gina Spencer (email@example.com), January 10, 2000
Gina, It seems what you're asking for is a brief tutorial on view camera movements. There are many texts on the subject, but perhaps you're in need of a overview as opposed to an in depth course and so I'll attempt to outline the important elements.
1. Shifts/Rise and Fall: Normally, the optical axis of the lens intersects a point exactly in the center of the film. By shifting the position of either the lens or film from left to right or vice versa, you will cause the image placement to change accordingly. The rise and fall movement is just shift turned sideways. The purpose of this adjustment is to allow you to recompose the image without tilting or panning the camera, thus avoiding upsetting the relationship of subject plane to film plane. Where you would use this might be when photographing architecture. To keep the sides of a building parallel, it would be necessary to keep the film plane parallel with the surface of the structure. If the building was tall and you wished to include its top in the image, by using the rise function, you could reposition the image on the groundglass without resorting to tilting up which would result in the sides of the building converging.
2. Tilts/Swings: It is with these movements that the Scheimpflug rule comes into play. Simply, if the subject plane, the lens plane (an imaginary surface that is perpendicular to the optical axis) and the film plane all intersect at one line, everything on the subject plane will be sharp regardless of how near or far it is from the camera. The classic illustration of how this works would be the image of railroad tracks where the camera is positioned between the rails and aimed down the tracks at the horizon. The tracks form the subject plane. The film plane (assuming a level camera) is perpendicular to the tracks and intersects it laterally across the rails. By tilting the lens panel forward to a point where the continuation of that surface (lens plane) just meets the the intersection of the subject and film plane, you would be free to focus anywhere along the tracks and have them in perfect focus from right under your feet to the point along the horizon where the tracks seem to dissappear! Swings are just tilts turned sideways. You would employ them wehn you need to keep a city block of store fronts in perfect focus from near to far.
You can manipulate certain cameras at both the front standard where the lens is mounted or the rear standard where the film goes. There are subtle differences in the way tilts and swings behave when you do them in the front as opposed to the rear of the camera. There are also some considerations related to the coverage of the lens (the size of the cone of light which the lens projects on the film) that sometimes makes it preferable to do tilts or swings at the rear as opposed to the front. It is also possible to combine a tilt and a swing in the same scene (compound Scheimpflug).
Another important point to make is that every movement will seem to solve one problem while at the same time creating another. What degree of movement and what type you use is determined by which problem is in greater need of being reduced and what compromise you are willing to live with. You can't have it all! Sometimes, though you can make it seem as though you've achieved just that!
I hope this helps and I'm certain others will have much to contribute.
-- Robert A. Zeichner (firstname.lastname@example.org), January 10, 2000.
Try this page from the B&H web site: http://www/bhphotovideo.com/photo/large/intro/introduction.html.
-- Chris Patti (email@example.com), January 11, 2000.
Take a look at Stroebel's "View Camera Technique". This book goes into great depth on the topics you are asking about.
-- Mark Windom (firstname.lastname@example.org), January 12, 2000.