Tilt techniques, Would you care to share your thoughts and Techniques.greenspun.com : LUSENET : Large format photography : One Thread
I'd like to start off by thanking those who shared Harold Merklingers focusing techniques with me. While on vacation in Utah, I applied his techniques and found them to be very usefull and accurate. I'm afraid however, his tilting techniques didn't quite click. In all fairness to Mr Merklinger, I only read it once, casually on the way to Utah. I would prefer however, to poll the readers of this fabulous site on what techniques you prefer.
With depth of field issues behind me, I'm open for suggestions on Tilting techniques. For those of you who have never heard of Harold Merlinger, you owe it to yourself to read what this fascinating gentleman has to share. I welcome your thougths...
Thanks again. Albert
-- Albert Martinez (email@example.com), August 21, 2000
Some will use all the math ever devised and get good results while others will tilt & focus and get good results. It is personal preference and varies with each photographers interests & desires. If I can stay away from the math, so much the better. I look at the image on the ground glass as I tilt, choosing either the front or back standard as needed to exaggerate or minimize any distortion. As I do this I re-focus an check with a small loupe when needed.
-- Dan Smith (firstname.lastname@example.org), August 21, 2000.
I'm with Dan on this one. I've read Merklinger's book "Focusing The View Camera" and he is right on the money with his theory. However, it is kind of difficult to apply in the field. It still seems to me that the photographer must know, before hand, both the vertical and horizontal distances to the principal objects in the scene that determine the principal plane of focus. I might be wrong here, if I am, please correct me.
So I look at the scean and visualize where I want the plane of sharp focus to be. I focus on the foreground, then tilt, then re-focus on the foreground. Then I examine the ground glass to see if my background object is also in focus. If not, I tilt one of the standards accordingly. Then I start over. The process continues until my plane of sharp focus cuts the foreground and the background where I want it to.
The trick is having an understanding of where the depth of field planes go as the standards are tilted. Merklinger does a fantastic job of describing this, but, I think an intuitive understanding or 'feel' for it is sufficient. At least for me anyway.
I hope this adds something to the discussion.
-- Jason Kefover (email@example.com), August 21, 2000.
I learned a technique from Tillman Crane at the Mammoth Camera Workshop in June that is quite useful, especially with large cameras where you can't easily reach the front standard from behind the camera. With hindsight it seems obvious, but I've never seen it mentioned in a book.
Suppose, for example, you're photographing an elevation of a building from an angle, and you want the plane of the elevation to be the plane of focus. Assume you've composed and focussed. Just walk to the position that is both in the plane of the elevation, by looking back at the building, and in the film plane, by looking back at the camera. Put something there, such as your camera case. The go back to your camera and adjust the lens board so that its plane includes the camera case. That's all there is to it. Scheimpflug without trial and error.
It seems most useful for determining front swing, but could also be used, with appropriate modification, for determining front tilt.
-- Stewart Ethier (firstname.lastname@example.org), August 21, 2000.
Rodenstock makes a plastic gadget for figuring tilt on one side and f stop on the other. B&H sells it for about $25.
My only caveat is the f stop finder seems to assume a circle of confusion about the size of jelly doughnut. So I stop down about another stop or two.
In actual practice I rarely use it. But it is good while you're getting the hang of tilting. One thing I got from Merkinlinger is that a little tilt goes a long way. I rarely use more than about three degrees for landscapes with longer lenses. Usually none for shorter lenses.
-- John Hennessy (email@example.com), August 22, 2000.
One thing I have found that helps a bit is an old ditty "Focus for the far, tilt for the near, then focus & tilt til all is clear". (I think it was Steve Simmons that told me this one) Whatever way you use, don't get it too complicated or you will find all the calculations eating into time better spent photographing.
-- Dan Smith (firstname.lastname@example.org), August 22, 2000.
Focus on the far, then tilt for the near works well with base tilt cameras. Generally the tilt will shift the focus, but with practice you get so you just automatically adjust tilt with one hand and focus with the other till it all comes together. If the camera has axis tilts, you would focus somewhere in the middle, then tilt to get the near and far, again ajusting focus. Practice in the field may be more useful than all the study and calculations you can do without the groundglass in front of you. Always bear in mind that you can never get a three dimensional scene into focus with tilts alone. A planar subject like beach and surf seen from above can be focused wide open with tilts alone. But if the picture is beach, surf, and then a tall lighthouse, the lighthouse will be way out of the plane of focus. Then you choose a compromise: you might run the focus plane (visually on the GG) from halfway up the lighthouse back to the edge of the surf. Then stop down to get the top of the lighthouse and the nearer part of the beach. ---Carl
PS: this is one place where bigger is better. It's much easier to see what's going on with a big groundglass so I actually find it faster and easier to find the right focus with my 8x10 than with smaller cameras.
-- Carl Weese (email@example.com), August 23, 2000.
I found Merklinger's book "Focusing the view camera" highly instructive, and very useful for focusing: it may appear a bit difficult at the beginning to estimate where the plane of focus should run unter the camera, but with a little bit of practice you just tilt once and then focus with the loupe. Sometimes I have to readjust the tilt a little, but if necessary, this is also done easily and fast, once the principle is understood. I have written the tilt degrees for the different lenths of j on the lensboard of each lens, and patched a rough angle scale on both of my wooden field cameras. For me at least, this procedure is easier and faster than any other, and I miss less scenes because the light changes before i am able to press the trigger.
-- Lukas Werth (firstname.lastname@example.org), August 25, 2000.