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G Benaim
22-Jun-2006, 02:08
Hello,

I have a pretty good idea of how to use and visualize each of these movements separately, but have a hard time seeing their effect together. Say you have a plane extending horizontally away ( a sidewalk, e.g.) and one vertically (e.g. a row of buildings along the sidewalk). Independently, one can easily see how tilt and swing, respectively, will help you match the plane of focus to the external plane. But what happens when they're used together? And how does one visualize it? Thanks for any help,

GB

Leonard Metcalf
22-Jun-2006, 03:41
I imagine the plane of sharp focus first (then I add in the curves of sharp focus - planes are not really all that will be in focus). Just in the same way as you can imagine a vertical receding plane as a swing, and a receding horizontal plane as a tilt. A diagonal plane will have a mixture of both. Most people would work out their movements in two steps, one for the horizontal and the other for the vertical, unless using a camera like a master technica which allows simultaneous adjustment of both planes (this is actually a joy to use in this situation).

Another way is to imagine three points in the image that you want to be in sharp focus, and use these to imagine your plane off.

Perhaps an example would help.
I firstly focus on point 2 as I am using a camera with asymmetrical movements. Point 2 is the point on the ground glass where everything hinges on (both swing and tilt) I focus on this one point.

Then I focus on point 1 by tilting the lens. Then I swing point three into focus as well. Finally I stop down the lens to ensure that my depth of field is appropriate to the image.

http://static.flickr.com/33/172546657_6a20a8a793.jpg

I hope this helps, regards,

Len

Leonard Evens
22-Jun-2006, 06:03
Keep in mind the shape of the region of adequate focus. It is always going to be a wedge centered on a hinge line. That hinge line will be the intersection of the plane of exact focus with a plane through the lens parallel to the film plane. For a tilt, it will be (usually) below the lens. For a swing, it will be a vertical line to the left or right of the lens. For a more general movement, like what you describe, it will be tilted with respect to both the vertical and the horizontal. Try to imagine where you want the plane of exact focus to be and then the resulting hinge line. When you finish with tilt and swing separately, the front standard should be parallel to this desired hinge line.

For the kind of scene you describe, it will be difficult, if not impossible, in the foreground to have both the sidewalk and the facades in adequate focus. That follows from the wedge shape and the fact that the apex of the wedge, the hinge line, will be skew with respect to both vertical and horizontal. You will probably have to decide which is more important to you, the vertical or the horizontal, get that in good focus with a tilt or swing as appropriate and then see if you can keep it in focus by using a slight perpendicular movement (swing or tilt as appropriate). The three pont method that Leonard M. recommended should enable you to do it if it is feasible, but I think there are few situations where it will actually work.

G Benaim
22-Jun-2006, 06:48
LM: Thanks for the diagram, that is very helpful.

LE: By wedge, do you mean 2-d or 3-d, i.e. a cone? I thought it wouldn't work, but it's likea puzzle that's kept going around in my mind. I can get the vertical plane w a swing, I can get the hor w a tilt, now how do I do both? I guess you get the second w dof as much as possible, right? Or does it make more sense to avoid movements and just stop down?

N Dhananjay
22-Jun-2006, 07:16
The DOF limits for a wedge - like a (very!) thick pizza slice, not like a cone.

As Leonard explained, if you use tilts and swings together, the plane of best focus is neither horizontal (parallel to the bed of the camera) nor vertical (to either side of the camera) but is angled to both planes. Say you are standing on a sand dune and want to photograph the ripples on the sand. The sand dune is rising in front of you but it is also rising from side to side such that it is lower on the left and higher on the right. Then, a combination of swings and tilts helps to get the ripples in focus. For the kind of situation you describe (sidewalk below and a building facade to be in focus), swings and tilts will not help you since they help you to get one plane into focus, whereas here you are trying to simultaneously get two planes into focus.

Cheers, DJ

G Benaim
22-Jun-2006, 11:22
DJ: That's a very clear explanation. So what's the best way to photograph two planes?

Ole Tjugen
22-Jun-2006, 14:07
So what's the best way to photograph two planes?

There isn't one.

The "best" way is to focus on the far point, and stop down as far as you can. There's a narticle by Harold merklinger somewhere on the net which explains the rationale behind this - and it really does work.

Back in the wet-plate days photographers often managed the seemingly imossible task of shooting street scenes that were sharp all over. They did this by exploiting the faults of their lenses! A simple meniscus lens has "horrible" field curvature, which means that the sides are in "near" focus when the center is focused on infinity. Some lens faults can occasionally be useful...

Leonard Metcalf
22-Jun-2006, 18:15
I have attached a diagram from p44 Stone J 1997 2nd Ed "A users guide to the view camera"... which shows the wedge that the other Leonard describes.. note that it is curved. (click on the thumbnail to see an enlarged view)

Following on from Ole Tjugen, Merkinger is worth seeing. In the article "Principles of View Camera Focus" by Harold Merkinger there are some fantastic little animations... these are fantastic for visualizing things such as the hinge rule... they can be down loaded from here. (http://www.trenholm.org/hmmerk/HMArtls.html)

Can I also suggest practicing at home... there is nothing like setting up and focusing the camera on various objects and see what you can do... stopping down the lens will work to a point before it gets to dark to see what is going on... then you need to take some snaps...

I particularly like the visualization of a wedge (thanks Leonard)

Regards,

Len

200

Leonard Evens
22-Jun-2006, 20:40
Imagine a note book with rigid covers. Open it up so it has a triangular cross section. Now imagine the binding reduced to a line and extended infinitely and imagine both covers extended infinitely. That is what the region looks like. When you see diagrams in books or articles, they usually show you just a perpendicular cross section. The hinge line or apex of the wedge becomes a point, and the bounding planes become lines. That can be very misleading unless you have the three dimensional model in mind. (Mathematically, the boundaries are actually called half planes since they extend in just in one direction from the hinge line.

Note that although the DOF region is in principle infinite from side to side along the hinge line, in practice, you also have to consider the angle of coverage of the lens. This does produce a cone centered on the lens which intersects the DOF wedge. Finally, the placement of the film frame will project outward and further limit what is in the field of view.

Leonard Evens
22-Jun-2006, 21:02
I've also seen the picture Leonard M. took from Stone's book before. But I am not sure just where it comes from. It is true that, in theory, the boundaries of the DOF region depart from planes. The reason is that since the exit pupil is not parallel to the film plane, the circles of confusion become ellipses of confusion. But I haven't seen any analysis which suggests that the departure from planes is as large as this diagram suggests. Wheeler, in his notes, analyizes the departure along the midline and finds it to be very small in practical situations for large format photography. I did my own analysis over the full field and found similar results. This was the topic of a long discussion either here or in photo.net several years ago.

Merklinger also proceeds on the assumption that the boundaries are planes.

It could be that Stone's diagram comes about from experimental measurements for some specific lens, which had large deviations from what geometric optics would predict. Surely there must be such deviations. For example, due to field curvature, the plane of exact focus is not even going to be a plane. But it would be surprising if it were as large as the diagram indicates. Also, it would be surprising to find that DOF increases as you go further out in the field, as the diagram seems to suggest. I will have to track down just where that diagram comes from.

Capocheny
23-Jun-2006, 01:09
GB,

IMHO, the image that Len posted from the Jim Stone book is one of the best illustrations you'll ever see on this subject matter :)

It's a great book and I'd suggest you find a copy.

Cheers

Leonard Metcalf
29-Jun-2006, 07:10
I knew I had one somewhere that had both swing and tilt together. taken in the Northern Territory of Australia at Lichfield National Park...
222

john borrelli
29-Jun-2006, 09:14
Leonard,
Your Lichfield photograph is quite beautiful. I'm sure if I had come across this scene I would not have been able to photograph it using tilt and swing with any thing like this kind of mastery. In fact, I probably would have been intimidated by the high vertical planes closest to the camera and tried to take the picture without movements maybe by just focusing a third of the way into the scene. As a newbie who benefits more from the description of how movements are used on actual landscapes (rather than in diagrams or in pictures of alphabet blocks), are there any specifics you could give us on this scene and your use of movements here. For example, Did you focus on a far point? If so,did you use tilt on the closest rock and swing on the rock to the right? Anything on lens choice, format and distances from camera to the different rocks? Or any info you think would be helpful to us in general would be appreciated. Thanks for your photo, John

Capocheny
29-Jun-2006, 09:38
Leonard,
Your Lichfield photograph is quite beautiful. I'm sure if I had come across this scene I would not have been able to photograph it using tilt and swing with any thing like this kind of mastery. In fact, I probably would have been intimidated by the high vertical planes closest to the camera and tried to take the picture without movements maybe by just focusing a third of the way into the scene. As a newbie who benefits more from the description of how movements are used on actual landscapes (rather than in diagrams or in pictures of alphabet blocks), are there any specifics you could give us on this scene and your use of movements here. For example, Did you focus on a far point? If so,did you use tilt on the closest rock and swing on the rock to the right? Anything on lens choice, format and distances from camera to the different rocks? Or any info you think would be helpful to us in general would be appreciated. Thanks for your photo, John

John,

I think you'd be awfully surprised at what YOU can do by looking on the ground glass when you try out some of the movements. That's all you have to do... look on the ground glass! Because, everything that will be rendered on film will be apparent when you look through the back of the camera. Perhaps, not right at the start... but you will get use to it!

I'd suggest you take the camera out into the backyard and just "play!" Do this on a nice, bright sunny day. The best way of learning is by doing...

Lastly, don't be intimidated by the movements. You won't need to make excessive movements like the ones you see in those pictures advertising cameras. Those pretzel-like movements are seldom used in real life situations. In fact, all you'll be needing is a very minimal amount of swings and tilts... especially in situations such as landscapes.

Now, if you're doing close-ups... that's a different story and you'll need a lot more swings and tilts. But, I'd really suggest you learn to walk before you run. The backyard is a good place to start! :)

Cheers

Leonard Evens
29-Jun-2006, 11:22
Leonard,
Your Lichfield photograph is quite beautiful. I'm sure if I had come across this scene I would not have been able to photograph it using tilt and swing with any thing like this kind of mastery. In fact, I probably would have been intimidated by the high vertical planes closest to the camera and tried to take the picture without movements maybe by just focusing a third of the way into the scene. As a newbie who benefits more from the description of how movements are used on actual landscapes (rather than in diagrams or in pictures of alphabet blocks), are there any specifics you could give us on this scene and your use of movements here. For example, Did you focus on a far point? If so,did you use tilt on the closest rock and swing on the rock to the right? Anything on lens choice, format and distances from camera to the different rocks? Or any info you think would be helpful to us in general would be appreciated. Thanks for your photo, John

I don't have a lot of experience simultaneously using both tilts and swings, but I think the scene shown prettty much cries out for such treatment. There is one plane encompassing the mostly vertical rock face in the foregournd and extending through the trees on the right in the middleground. A pure swing won't do it because the rock face is not really vertical, but makes about a 75 degree angle with the vertical. I would start with a swing, trying to get the middle of the rock face, the trees, and the distant parts of the scene in focus. The front standard would be swung back on the left but not by too far. (Left/right here are when looking from the rear towards the scene.) I would then experiment with tilting forward slightly so that in the end the upper right corner of the standard was further forward and the lower left corner further back. The reason is that the subject plane should incline from upper left to lower right and also from behind the camera on the left and then slightly to the right as you move away from the lens.

If you can visualize where you want the plane of exact focus to go, you can visualize the axis about which the front standard should rotate because that axis should be parallel to the subject plane. Unfortunately, you can't rotate directly about that axis but have to insead approximate such a roatation by combining a swing and a tilt. If you place a straight edge on the lensboard where the roation axis should be, that might help you see if it is parallel to the desired subject plane as needed. Fortunately, you don't have to get it exactly right to improve the situation, as long as you are going more or less in the right direction. Looking at the gg will tell you if you have got close enough for your purposes.

Leonard Metcalf
29-Jun-2006, 18:58
For an asymmetrical camera. I use an Ebony 45SU. I focused on the near LHS receding rock at the point where the rear ground glass swings and tilts pivot around. This is approximately (on my camera) 1/2 inch from the side and 1 1/2 inches from the bottom. Luckily this point is clearly marked on the ground glass. Then I would swing the background into focus, by trying get the end of the rock in correct focus (ie the furthest part of the receding rock). I didn't worry about the RHS or the far distance. I then tilted to bring the bottom of the rock into sharp focus. Lastly, I just stopped down and hoped.

Note: by using rear movements I have intentionally changed the shape of the image and increased the fore shortening effect. If you don't want to do this you have to use the lens movements. By stretching the rock I added extra emphasis by increasing its size in proportion to the rest of the image.

If I had a camera that swings and tilts around the center axis, as most monorails do. You have to start in the middle of the plane that you wish to focus on.

If you have a field camera with base tilts, you have just keep adjusting over and over till you find the sweet spot.

For this sort of shot I actually also liked using the fully floating back in a Linhof Technica.. You would pull the whole back out 2/3rd of the way, then freely swing and tilt simultaneously... to find the plane of sharp focus.

In summary I only concentrated on focusing on the receding plane and left the rest of the image to see what happens, and to help this, I closed down the lens to maximize depth of field and to increase the blurring of the waterfall.

The details are: 4 x 5 inch camera, Schneider Super Symmar XL 110mm at f45 - 1/4 second on HP5 + at N. Florence Falls. 22nd January 2006

john borrelli
4-Jul-2006, 10:44
Thanks to everyone, particularly Leonard E. and Leonard M. for the details. I will definitely study them as well as practice with my camera. Leonard M. there was an article in View Camera Magazine a little while ago on the use of asymmetrical movements by Richard Sexton. It is a very good article but I think your description is better. I think the article included photos that illustrated the concepts being discussed and so the article was not driven by the strength of a wonderful image. Though the last of his three images was very nice but unfortunately if memory serves, the image was not detailed with reference to movements, etc. I make this reference because I was thinking your photo and description would make a good view camera article. In fact, it would be great for someone like myself if Steve Simmons had a "Last Image" type column every issue where a large format photographer wrote on equipment, camera movements and perhaps a little on the experience of being there, the mood and how the photographer's use of the equipment helped the artist to translate that experience of being there into an effective photo. I don't mean to sound negative about Leslie Stroebel's book View Camera Technique, but (as I alluded to in a previous post about alphabet blocks) this kind of info is more helpful, I think, to the beginner. So thank you all again, John

Capocheny
4-Jul-2006, 16:40
I make this reference because I was thinking your photo and description would make a good view camera article. In fact, it would be great for someone like myself if Steve Simmons had a "Last Image" type column every issue where a large format photographer wrote on equipment, camera movements and perhaps a little on the experience of being there, the mood and how the photographer's use of the equipment helped the artist to translate that experience of being there into an effective photo. I don't mean to sound negative about Leslie Stroebel's book View Camera Technique, but (as I alluded to in a previous post about alphabet blocks) this kind of info is more helpful, I think, to the beginner. So thank you all again, John

Hi John,

I couldn't agree with you more and, IIRC, I had made a suggestion to that effect when Steve was asking for suggestions as to what articles his reading public wanted. That was a short while ago and I sincerely hope View Camera Magazine takes it to heart!

Still have my fingers crossed! :)

As for the Stroebel book, although it's a great reference book, it can be difficult to conceptualize and visualize many of the ideas for new view camera users. I relied on the Jim Stone, and Jack Dykinga, books when I first started because they were written in a much more "understandable" writing style... and less technical! Plus, they were more graphical, which helped. :)

But, at the end of the day... the best way to learn how to use one of these cameras is to take it out into the field and experiment, experiment, experiment! :)

Cheers