My Chamonix 45H-1 comes with asymmetrical tilt on the back standard only. That works fine and requires one iteration to get focus front and rear. But you can distort the picture since you're changing the film tilt. You can avoid the distortion by tilting the front standard. But then, you have to use numerous iterations to get the focus right as there's no asymmetrical tilt on the front standard.
Flickr Home Page: https://www.flickr.com/photos/alanklein2000/albums
I have -- in situations where I have had to use back tilt to get the trees pointing in the direction I want, and the front to clean up the focus.Originally Posted by Alan9940
"Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China
In my scenic pictures, I often tilt the back vertical to render vertical lines parallel. Thus mostly I use both front and back tilts with my 5x7 Canham wood. If my lens has narrow field of view it is possible to get the full image on the film with back tilts when doing the same near-far with front tilts might make the image fail at the corners.
In the 1960s I met David Windsor, U of Chicago photographer. We became friends and met often at lunch. I was skilled at machining, so he asked me to add front tilts to his 8x10 Kodak view camera. He told me that he could get proper focus with only the existing rear tilt, but it took so long that the spectators would become bored and go away.
Best wishes --- Allen Anway
It took me too long to realize that pointing the camera up, straightening the back to vertical, and then adjusting front tilt to bring things into focus was pretty much the same thing as keeping the camera level and just using front rise.
Using a 5x7 camera having back tilt and no front tilt reinforced that for me.
"Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China
No one has mentioned this, but if you tilt the rear back, you must compensate by stopping the lens down much further that when front tilt is used. The depth of focus required for say a 1" tilt of the top of the rear frame is 1". Depth of focus is the similar to depth of field, but it resides at the image plane. If you tilt the front this Depth of focus does not increase at the same rate as it does when tilting the back.
Ansel Adams has a shot I know of where he used both front and rear tilt to get extreme depth of filed. It is a shot of tree roots. To accomplish this you need the camera quite low to the ground. Tilt the back until the near is sharp or you begin to vignette. If you are just starting to vignette then ease off until you are no longer vignetting. Now begin to tilt the front to try and get the entire subject sharp. And do not forget to stop down some extra, as well. This is the name of Ansel's image
Ansel Adams
Roots, Foster Gardens, Honolulu
1948
Excellent, that's a bit of information that's eluded me up to now--very useful!
Changing the position of the plane of sharp focus by tilting (or swinging) either the back or the front is really not specifically related to either depth-of-field or depth-of-focus. Aperture, focal length (magnification) and distance from the film plane are the important factors.
While it's true that changing the position of the plane of sharp focus creates a situation in which parts of this plane are at various distances from the focus plane (unlike when the standards and the plane of sharp focus are all parallel), it would still be possible to focus on a flat plane without stopping down at all. Depth-of-field issues only arise when objects lie outside the plane of sharp focus (near objects outside the plane of sharp focus requiring more depth-of-field). Depth-of-focus issues have more to do with lens focal length than camera manipulations, with short focal-length lenses exhibiting less depth-of-focus than longer ones all other things being equal.
As has been pointed out several times in this thread, a particular relationship of camera back to lens plane can be achieved with either back or front movements or a combination of the two. If, say, we set up a shot and tilt the back for focus, we could also obtain an identical relationship of back, lens and focus planes by tilting the front and then using the tripod head to tilt the entire camera back a bit. I can't see where the former would require more stopping down than the latter...
By the way, tilting the back keeps the film within the lens' cone of projection; back tilts or swings are not going to cause vignetting. It's the front tilts/swings that move the lens' cone of projection around that will run you out of coverage quickly.
The Ansel Adams image you refer to probably required both front and rear tilt simply because one movement alone was not adequate due to the physical limitation of the camera used. The amount of stopping down needed (whatever that was) depended on the irregularity of the subject, not the fact that back tilt was used.
Sorry to rain on your parade, but misconceptions like this tend to confuse and end up being unhelpful, especially to newcomers to the craft.
Best,
Doremus
Books about large format photography or view cameras often have photos to illustrate the effects of various movements that can be very helpful, especially for the newcomer; people with years of experience have probably internalized all this. When you have tilts on both axes plus the focusing movement along the axis, sometimes finding the correct plane of focus can be confusing. There are a couple of step by step guides to focusing the camera on the LFphoto homepage that may be helpful.
I looked in Simmons's "Using the View Camera" and there isn't an illustration exactly corresponding to this, so here is a crude drawing of a side view of the effects of front, back, and both tilts (not to scale). Click to embiggen.
At this stage of the game, I find any and all data points of value--thanks for everyone's generosity!
A question for you: in my part of the world, it's pretty much a given that there will be objects protruding above and below the plane-of-focus; is there a rule-of-thumb I might go to under field conditions to determine the largest useable aperture that will provide enough "depth" to that plane? Up to this point, with my movements mostly limited to rise/fall, I've used my Sinar Norma's focus scales in conjunction with a published aperture table to negotiate the DOF vs. diffraction trade-off, but I'm not sure how to negotiate the addition of tilts/swings. (FWIW, I'm almost always working under pretty dense canopy, so checking focus with the lens at the shooting aperture is pretty much a "through a glass darkly" scenario.)
I'm an enthusiastic user and proponent of the method for choosing the optimum aperture based on focus spread described in the article on the LF Home Page here: https://www.largeformatphotography.info/fstop.html .
It's a bit of a long read, but well worth it. In short, however, you simply measure the distance difference between front and rear standards focused on the nearest and farthest object you want in sharp focus and choose your f-stop accordingly.
When applying this method when using tilts or swings, you need to keep in mind where the plane of sharp focus is located in the scene and adjust your idea of "near" and "far" accordingly. For example, using lots tilt to lay the plane of sharp focus down almost horizontally (as one might do with a flat foreground and distant mountain scene) ends up placing "near" objects above the plane of sharp focus and "far" objects below it. Once you can deal with that, however, the method is straightforward, foolproof and it's easy to use in low light.
Have fun,
Doremus
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