Camera Movements

[Chuck_P]

I normally don't choose compositions that may require too many movements because I always seem to have trouble and yesterday was no exception.....I attempted some image management using front rise, front swing, front tilt, and rear swing. The front rise is not part of the problem here, that's simple enough. As you can imagine it's the swings and tilt that make me feel like a dog chasing it's tail. From the diagram, you can see the orientation of the camera to the building, and the tree is closer to the building than the diagram depicts.

One question is..........is there an order in which the movements should be applied to make the whole process smoother? Another question......I've never tried using both front swing and front tilt in the same image, is that doable? I understand "focus on far, tilt on near".......is it the same for swing: focus on far, swing on near? I attempted the movements in the following order:

1st, front rise
2nd, rear swing to keep the back parallel to the front of the building
3rd, front swing to place a focal plane parallel to the front of the building
4th, front tilt to try and maintain focus on the foreground tree and ground.

I did expose a negative (not developed yet), and am certain there are probably focus issues, I'll find out later today. Also, it did not help that yesterday was so windy and that was problem in itself. I could not use the dark cloth, but managed to use the jacket with hood I was wearing to see the gg better. The wind forced me to keep the shutter speed faster than I wanted because I felt that I needed as much DOF as possible, feeling certain that focus was not the best it could be.

Edit: My camera is a Canham DLC45 with base tilt.

 

[rcphoto]

Brave man getting a big camera out in yesterdays wind. We had 30mph winds and gusts that felt like 60+ by Lake Cumberland but my weather station didn't record them.

 

[Chuck_P]

Brave man getting a big camera out in yesterdays wind. We had 30mph winds and gusts that felt like 60+ by Lake Cumberland but my weather station didn't record them.

Well, it was manageable but annoyingly so. I'm in Daviess County and wanted to photograph the bridge at Owensboro with the white caps on the Ohio River, but the camera position required it to be subjected to cross winds. There was no way I was going to risk that because I feared for the bellows being damaged and camera being blown over. Where I photographed yesterday the position was subjected to the head wind, so I found it more manageable.

 

[abruzzi]

I don't know the Canham, but ont thing that can potentially cause issues is Yaw. You'll usually see see yaw discussed in relation to indirect rise--basically where you need extreme rise--more than you camera has--so you compensate by tilting the whole camera upwards then using tilt to get the standards back where you want them. On some cameras you can do that then swing the front without affecting the tilt because they are yaw free, but other cameras are not and the last step--adjusting the swing in this example affects the tilt.

From your description it sounds like you are doing the same thing, but then starting with swing, then adjusting tilt. I think if the tilt pivot is above the the swing pivot on your camera, you won't have the issue (yaw is always a little hard to visualize).

Otherwise, the order you state is probably the order I'd use--if I used all of them, however, I try to avoid back tilt/swing movements. Instead, I'd probably position the whole camera so the back is parallel to the building, then compensate with assitional shift to frame the photo--unless, like above, I didn't have enough shift on the camera and needed to do "indirect shift."

 

[Vaughn]

Swing to put the plane of focus along the front of the building, then back up the focus to between the tree and building, close the lens down to check DoF and take the photo.

No tilt -- causes more problems in this case than it cures.

Why keep the back parallel to the building? You might try giving the building the shape it normally has when seen from that angle.

 

[Chuck_P]

ou'll usually see see yaw discussed in relation to indirect rise--basically where you need extreme rise--more than you camera has--so you compensate by tilting the whole camera upwards then using tilt to get the standards back where you want them.

I can't remember if I tilted the camera up before utilizing rise, thanks, I will keep this thought in mind going forward. I take it that I should be able to learn to utilize front tilt and swing in the same image, I will need to practice a lot.

 

[Alan Edward Klein]

I'm new to LF so I commiserate with you. We ought to start a thread where we can post pictures and ask what people would do to use the best swing and tilts or not.

In this case, Vaughn is right. Use aperture only to control for the best DOF. When you have a tall object in the front, if you tilt, then the top of the tree which may be higher than the far building is not in the close plane of focus and will be less sharp. Tilt would work if there was a short close object like a rock or flowers.

One comment about the DOF. It's 1/3 before and 2/3 after the place you focus. So it should be 1/3 not halfway the distance between the near and far points unless you are using the bellows adjustment to calculate the middle between the far and near focus points. Then it works automatically.

I also keep a DOF chart with me for each lens. You can select the lens and 4x5 format or for any other camera and lens and print it out.

Depth of Field Table

Depth of Field Table

dofmaster.com

Here's a DOF calculator that's handy too.
DOF Calculator

 

[abruzzi]

I can't remember if I tilted the camera up before utilizing rise, thanks, I will keep this thought in mind going forward. I take it that I should be able to learn to utilize front tilt and swing in the same image, I will need to practice a lot.

The main gist is if you use both angular movements (swing and tilt) on the same standard it’s possible that one movement affects the other. You’ll have to look and see which affects what on your camera.

 

[Doremus Scudder]

I normally don't choose compositions that may require too many movements because I always seem to have trouble and yesterday was no exception.....I attempted some image management using front rise, front swing, front tilt, and rear swing. The front rise is not part of the problem here, that's simple enough. As you can imagine it's the swings and tilt that make me feel like a dog chasing it's tail. From the diagram, you can see the orientation of the camera to the building, and the tree is closer to the building than the diagram depicts.

One question is..........is there an order in which the movements should be applied to make the whole process smoother? Another question......I've never tried using both front swing and front tilt in the same image, is that doable? I understand "focus on far, tilt on near".......is it the same for swing: focus on far, swing on near? I attempted the movements in the following order:

1st, front rise
2nd, rear swing to keep the back parallel to the front of the building
3rd, front swing to place a focal plane parallel to the front of the building
4th, front tilt to try and maintain focus on the foreground tree and ground.

I did expose a negative (not developed yet), and am certain there are probably focus issues, I'll find out later today. Also, it did not help that yesterday was so windy and that was problem in itself. I could not use the dark cloth, but managed to use the jacket with hood I was wearing to see the gg better. The wind forced me to keep the shutter speed faster than I wanted because I felt that I needed as much DOF as possible, feeling certain that focus was not the best it could be.

Edit: My camera is a Canham DLC45 with base tilt.

Okay, let me dissect this a bit.

First, front rise is simply framing. As long as you have a large enough image circle, there's no problem. However, do be careful when tilting the lens down after applying front rise, since downward tilt on the front standard moves the image circle up on the film and can cause vignetting.

Second, your setting up the camera and then swinging both back and front parallel to the building façade is the same thing as using lateral shift. I don't know if your camera has lateral shift, but if it does, you can often use that to accomplish what you were trying to do. Keep in mind that when you do this (however it's done, either with shift or with the "point and swing both standards parallel" method), you are placing the optical center of the image off-center on the film. I like this effect and use it intentionally often.

So far, so good; you have the building rendered parallel and the entire façade in sharp focus and you have used front rise to get the framing you want.

Now on to tilt. When shooting architecturals, you likely don't want to tilt the back away from plumb in order to keep the vertical parallel lines from converging on the film. So front tilt is the way to go, if it will help. This latter is the big question. As you can see from the above posts, many just assume that it won't help at all and just stop down. This is often a good approach since the benefit of front tilt in a situation like this can be quite small and it takes time to apply the tilt and check everything. If stopping down gets the job done without moving past f/32 on 4x5, I'd maybe just stop down too.

That said, front tilt can often help a bit in situations such as you describe as long as the top of the tall object in the foreground (tree in your case) is not above the top of the tall background object (building) in the image you are making (Note: this is not about actual height, but the position of the tops of near and far objects from the camera point of view). If the tree top does appear lower than the building top, then you can set your tilt as follows to get a bit more of your image closer to the plane of sharp focus:

First, focus on the top edge of the distant building, or the highest point if there's something like a steeple or statue or whatever. Then choose a foreground low object that you wish to have in focus. I'll often use a pebble on the ground or whatever. Tilt (however you do it) so that both these objects lie in the plane of sharp focus (PoSF). I have base tilts, so it's tilt till both are equally unsharp, refocus on the far, check and adjust tilt for the near and repeat till all is sharp. It should be the same with your Canham.

Once you've done this, you have the optimum tilt, but - this is important - not the proper focus. Now you need to choose focus points and place the standards halfway between them. The position you've just finished applying tilts with is your near focus (it's focused on the near pebble, remember?), so note that position. Now find the far; it could be hills in the background or whatever, but don't overlook the point where the ground and building intersect. When you apply tilt, often this point ends up being the farthest, optically, from the PoSF. Once you've found the point that requires the most focus spread, place your standards halfway between that. That's optimum focus.

Now you just need an f-stop that keeps everything in focus. I use tables derived from the article on the Large Format Photography home page here: https://www.largeformatphotography.info/fstop.html . Choose your f-stop depending on focus spread and you're good to go.

FWIW, you applied the movements in the correct order for having base tilts, i.e., when using both swings and tilts, apply the tilt last. It's when you apply tilt and then swing that you can get yaw. Yaw isn't that big of a problem with the front standard but it will throw off your careful placement of the PoSF. Any case, any distortion or displacement of the image due to yaw will be visible on the ground glass.

Hope this helps,

Doremus

 

[Alan Edward Klein]

Okay, let me dissect this a bit.

First, front rise is simply framing. As long as you have a large enough image circle, there's no problem. However, do be careful when tilting the lens down after applying front rise, since downward tilt on the front standard moves the image circle up on the film and can cause vignetting.

Second, your setting up the camera and then swinging both back and front parallel to the building façade is the same thing as using lateral shift. I don't know if your camera has lateral shift, but if it does, you can often use that to accomplish what you were trying to do. Keep in mind that when you do this (however it's done, either with shift or with the "point and swing both standards parallel" method), you are placing the optical center of the image off-center on the film. I like this effect and use it intentionally often.

So far, so good; you have the building rendered parallel and the entire façade in sharp focus and you have used front rise to get the framing you want.

Now on to tilt. When shooting architecturals, you likely don't want to tilt the back away from plumb in order to keep the vertical parallel lines from converging on the film. So front tilt is the way to go, if it will help. This latter is the big question. As you can see from the above posts, many just assume that it won't help at all and just stop down. This is often a good approach since the benefit of front tilt in a situation like this can be quite small and it takes time to apply the tilt and check everything. If stopping down gets the job done without moving past f/32 on 4x5, I'd maybe just stop down too.

That said, front tilt can often help a bit in situations such as you describe as long as the top of the tall object in the foreground (tree in your case) is not above the top of the tall background object (building) in the image you are making (Note: this is not about actual height, but the position of the tops of near and far objects from the camera point of view). If the tree top does appear lower than the building top, then you can set your tilt as follows to get a bit more of your image closer to the plane of sharp focus:

First, focus on the top edge of the distant building, or the highest point if there's something like a steeple or statue or whatever. Then choose a foreground low object that you wish to have in focus. I'll often use a pebble on the ground or whatever. Tilt (however you do it) so that both these objects lie in the plane of sharp focus (PoSF). I have base tilts, so it's tilt till both are equally unsharp, refocus on the far, check and adjust tilt for the near and repeat till all is sharp. It should be the same with your Canham.

Once you've done this, you have the optimum tilt, but - this is important - not the proper focus. Now you need to choose focus points and place the standards halfway between them. The position you've just finished applying tilts with is your near focus (it's focused on the near pebble, remember?), so note that position. Now find the far; it could be hills in the background or whatever, but don't overlook the point where the ground and building intersect. When you apply tilt, often this point ends up being the farthest, optically, from the PoSF. Once you've found the point that requires the most focus spread, place your standards halfway between that. That's optimum focus.

Now you just need an f-stop that keeps everything in focus. I use tables derived from the article on the Large Format Photography home page here: https://www.largeformatphotography.info/fstop.html . Choose your f-stop depending on focus spread and you're good to go.

FWIW, you applied the movements in the correct order for having base tilts, i.e., when using both swings and tilts, apply the tilt last. It's when you apply tilt and then swing that you can get yaw. Yaw isn't that big of a problem with the front standard but it will throw off your careful placement of the PoSF. Any case, any distortion or displacement of the image due to yaw will be visible on the ground glass.

Hope this helps,

Doremus

Here is a question I asked previously but no one answered. Maybe you can provide it?

How do you find the far and near focus points after you completed the tilt portion? (From your post: "Once you've done this, you have the optimum tilt, but - this is important - not the proper focus. Now you need to choose focus points and place the standards halfway between them.")

 

[Chuck_P]

That said, front tilt can often help a bit in situations such as you describe as long as the top of the tall object in the foreground (tree in your case) is not above the top of the tall background object (building) in the image you are making

I believe the tree top in this instance was above the top of the building behind it, will know after developing. As you describe it I see it perfectly but it did not occure to me at the time.

FWIW, you applied the movements in the correct order for having base tilts, i.e., when using both swings and tilts, apply the tilt last.

Good to I did it correctly, although I must admit that it just seemed logical but I really didn't know why.

 

[Kilgallb]

One comment about the DOF. It's 1/3 before and 2/3 after the place you focus. So it should be 1/3 not halfway the distance between the near and far points unless you are using the bellows adjustment to calculate the middle between the far and near focus points. Then it works automatically.

I get why we can use this as a guide, but why not just look at the image on the ground glass to confirm?

 

[Vaughn]

I get why we can use this as a guide, but why not just look at the image on the ground glass to confirm?

I believe most of us do that. My favorite trick is to study the GG as I reduce the aperture. If near and far come into sharp focus at the same time, then I have the plane of focus at the optimal place. It can be challenging in the temperate rain forests, but f64 and f90 (and patience) are our friends.
But I remember early on tying the bellows in knots trying do figure things out on the GG, only to re-zero everything and apply minimal movements instead. Fun, though.

 

[Reginald S]

One comment about the DOF. It's 1/3 before and 2/3 after the place you focus. So it should be 1/3 not halfway the distance between the near and far points unless you are using the bellows adjustment to calculate the middle between the far and near focus points. Then it works automatically.

Some comments about this ghostlike appearing rule:
It's only true for only one subject distance, and this to each aperture.

The real rule is this:
The depth of field depends on subject distance, focal length and aperture.

On your DOF Chart the you also will find a hyperfocal distance (HD) calculator.
HD means focusing to a certain distance determines the front limit of the depth of field and the back limit of the depth of field, bringing all subjects inbetween to an acceptable sharpness.

Calculating the HD by math also includes the circles of confusion and the diameter of the entrance pupil which depends on aperture's size.

Going deeper to the theory of HD you will find some dump rules, for example:
"
If the focal distance is one third of the hyperfocal distance, then the
depth of field behind the focal plane is is twice as large as the depth forward the focal plane."

Note: IF.
If not, then not.

For those enjoying math for finding out the correlations between the
distances from the camera to the front and rear limits of the depth of field and the focus distance, which then applies to all apertures and
distances:

focal distance = (2x front limit of DOF x back limit of DOF) divided through (front limit of DOF plus back limit of DOF).

You will find that your given ratio 1/3 to 2/3, or 1:2, is only the case if the distance of the back limit of DOF is twice as the distance of the front limit of DOF.

I am referring to a german dissertation from H. Nasser given to Zeiss Optics.
Date: 2010
Title: "Depth Of Field, And Bokeh"

Hopefully my translation of text and formula is correct.

 

[Reginald S]

Here is a question I asked previously but no one answered. How do you find the far and near focus points after you completed the tilt portion?

In the other forum I gave some detailed answers around focusing and also finding the needed aperture which there you have found helpful.

I referred to Mr. Schön/Linhof and Mr. Merklinger, including drawings and videos concerning Scheimpflug,Hinge Rule, movements.

The visual answer to your question lies in the little movie showing the movements of the plane of sharp focus while turning the focus knob.
Understand the limits on top and on the buttom as "near" and "far" points and as seen in the link to Mr. Schön's manual "finding angles and sharpness".

 

[Alan Edward Klein]

I'm new to LF so I commiserate with you. We ought to start a thread where we can post pictures and ask what people would do to use the best swing and tilts or not.

In this case, Vaughn is right. Use aperture only to control for the best DOF. When you have a tall object in the front, if you tilt, then the top of the tree which may be higher than the far building is not in the close plane of focus and will be less sharp. Tilt would work if there was a short close object like a rock or flowers.

One comment about the DOF. It's 1/3 before and 2/3 after the place you focus. So it should be 1/3 not halfway the distance between the near and far points unless you are using the bellows adjustment to calculate the middle between the far and near focus points. Then it works automatically.

I also keep a DOF chart with me for each lens. You can select the lens and 4x5 format or for any other camera and lens and print it out.

Depth of Field Table

Depth of Field Table

dofmaster.com

Here's a DOF calculator that's handy too.
DOF Calculator

I should have stated adjust focus to 1/3 into the picture to get the approximate placement for focusing from the front focus point to rear. The DOF charts help to find the distance and just set the focus there as best you can. Then add one more step down. I;ve never had much luck with 35mm and MF using step down aperture to view the scene as it gets too dark. How do photographers see anything at f22 or f32 on a LF camera?

 

[Alan Edward Klein]

In the other forum I gave some detailed answers around focusing and also finding the needed aperture which there you have found helpful.

I referred to Mr. Schön/Linhof and Mr. Merklinger, including drawings and videos concerning Scheimpflug,Hinge Rule, movements.

The visual answer to your question lies in the little movie showing the movements of the plane of sharp focus while turning the focus knob.
Understand the limits on top and on the buttom as "near" and "far" points and as seen in the link to Mr. Schön's manual "finding angles and sharpness".

I don't recall seeing an answer to my particular problem.

Since my camera has rear asymmetrical tilt, I only focus the bellows on the far point. Then I tilt back the back standard to place the near focus point in the plane of focus and get the near in focus. So how do I find the middle of the far and near focus points to calculate the aperture setting and readjust the bellows focus?

 

[Doremus Scudder]

Here is a question I asked previously but no one answered. Maybe you can provide it?

How do you find the far and near focus points after you completed the tilt portion? (From your post: "Once you've done this, you have the optimum tilt, but - this is important - not the proper focus. Now you need to choose focus points and place the standards halfway between them.")

Alan,

I've answered this before for you But here it is again:

You have to visualize where the plane of sharp focus lies in the scene. And, you have to know how depth of field works when part of the PoSF lies closer to you and then recedes so you can choose which points to use as focus points.

First, let’s look at a situation without tilt. Let's start with the camera in zero position and set up plumb and level. Say we have two sets of objects that are 10 feet apart, one set close to the camera and one set much farther away, arranged on a line perpendicular to the PoSF (which is parallel to the camera back). It should be easy to see that the focus spread between an object five feet from the camera and another 15 feet from the camera will be greater than the focus spread between objects 40 and 50 feet from the camera.

If you wanted to focus on the two near objects only, and everything between, you'd place the focus on the camera bed/rail halfway between the positions for five feet and 15 feet. If you wanted to do the same for the far set of objects, you'd set your focus on the camera bed/rail halfway between the positions for 40 and 50 feet. If you wanted to get the everything between five and 50 feet in focus, you'd have to set the focus on the camera bed/rail halfway between the focus positions for the five and the 50-foot objects.

Of course, then you need the right f-stop to get both ends sharp. The greater the focus spread, the smaller the f-stop you need to get everything inside the limits of DoF. So, the case with the smallest focus spread, (between 40 and 50 feet) would allow the largest aperture. The case with the largest focus spread (the 5-50-foot spread) would need a much smaller aperture. In all these cases, "near" and "far" make pretty good sense; they are actually near and far.

Now let's look at a case in which the PoSF is laid down at a 45° angle using tilt. From the above, we know that the DoF at the near part of the PoSF will not be as great as the DoF farther away. You can visualize the DoF as a wedge extending on either side of the PoSF and growing wider the farther it gets from the camera position. It also grows wider with smaller apertures.

But when you use tilt to position PoSF at 45° to the camera back, "near" and "far" get a bit more complicated. If you visualize the PoSF in such a case, you can see that some objects could be above it and some could be below it. So, you could have a near (to the camera) object, part of which is above the PoSF and part of which is below it (think maybe of a near fence post with the PoSF going through the middle of it). The focus spread between the two ends of the fence post could easily be the largest focus spread you have in the scene, so you'd have to take the "above" end of the fence post as your "far" point and the below part of the fence post as your "near" point.

In other words, when tilting (or swinging) "near" and "far" focus points often have nothing to do with actual distance from the camera or actual distance from the PoSF, but rather how far you have to move the focus knob to get different points in focus.

In practice, this means being aware of where the PoSF lies in the scene and looking for objects at any actual distance from the camera that might end up functioning as “near” and “far” focus points for use focusing the camera. You might have to try a few combinations, but always choose the pair that give you the greatest focus spread. Then, note the distance of the focus spread on the camera bed/rail and choose the f-stop accordingly using the table you have or whatever you do.

Oh, one more thing: The situation I described for Chuck involved using tilt to put two very near objects in the PoSF. In this case, once the tilt has been applied, there are no objects "closer to the camera" or "above" the PoSF, which means that the focus position is already focused on the "near." So, all that remains is to find the "far" (or "below") and determine focus spread. Applying tilt using reference points that will end up being the "near" is a trick I use a lot and eliminates a step in focusing.

Hope this helps,

Doremus

 

[Alan Edward Klein]

Alan,

I've answered this before for you But here it is again:

You have to visualize where the plane of sharp focus lies in the scene. And, you have to know how depth of field works when part of the PoSF lies closer to you and then recedes so you can choose which points to use as focus points.

First, let’s look at a situation without tilt. Let's start with the camera in zero position and set up plumb and level. Say we have two sets of objects that are 10 feet apart, one set close to the camera and one set much farther away, arranged on a line perpendicular to the PoSF (which is parallel to the camera back). It should be easy to see that the focus spread between an object five feet from the camera and another 15 feet from the camera will be greater than the focus spread between objects 40 and 50 feet from the camera.

If you wanted to focus on the two near objects only, and everything between, you'd place the focus on the camera bed/rail halfway between the positions for five feet and 15 feet. If you wanted to do the same for the far set of objects, you'd set your focus on the camera bed/rail halfway between the positions for 40 and 50 feet. If you wanted to get the everything between five and 50 feet in focus, you'd have to set the focus on the camera bed/rail halfway between the focus positions for the five and the 50-foot objects.

Of course, then you need the right f-stop to get both ends sharp. The greater the focus spread, the smaller the f-stop you need to get everything inside the limits of DoF. So, the case with the smallest focus spread, (between 40 and 50 feet) would allow the largest aperture. The case with the largest focus spread (the 5-50-foot spread) would need a much smaller aperture. In all these cases, "near" and "far" make pretty good sense; they are actually near and far.

Now let's look at a case in which the PoSF is laid down at a 45° angle using tilt. From the above, we know that the DoF at the near part of the PoSF will not be as great as the DoF farther away. You can visualize the DoF as a wedge extending on either side of the PoSF and growing wider the farther it gets from the camera position. It also grows wider with smaller apertures.

But when you use tilt to position PoSF at 45° to the camera back, "near" and "far" get a bit more complicated. If you visualize the PoSF in such a case, you can see that some objects could be above it and some could be below it. So, you could have a near (to the camera) object, part of which is above the PoSF and part of which is below it (think maybe of a near fence post with the PoSF going through the middle of it). The focus spread between the two ends of the fence post could easily be the largest focus spread you have in the scene, so you'd have to take the "above" end of the fence post as your "far" point and the below part of the fence post as your "near" point.

In other words, when tilting (or swinging) "near" and "far" focus points often have nothing to do with actual distance from the camera or actual distance from the PoSF, but rather how far you have to move the focus knob to get different points in focus.

In practice, this means being aware of where the PoSF lies in the scene and looking for objects at any actual distance from the camera that might end up functioning as “near” and “far” focus points for use focusing the camera. You might have to try a few combinations, but always choose the pair that give you the greatest focus spread. Then, note the distance of the focus spread on the camera bed/rail and choose the f-stop accordingly using the table you have or whatever you do.

Oh, one more thing: The situation I described for Chuck involved using tilt to put two very near objects in the PoSF. In this case, once the tilt has been applied, there are no objects "closer to the camera" or "above" the PoSF, which means that the focus position is already focused on the "near." So, all that remains is to find the "far" (or "below") and determine focus spread. Applying tilt using reference points that will end up being the "near" is a trick I use a lot and eliminates a step in focusing.

Hope this helps,

Doremus

I feel like a dodo bird. Thanks for being patient with me. But I'm still confused when using asymmetrical tilt. RIght now I only focus once. That's at the far distance point. Then I tilt the rear standard to focus the near object. That's it. I'm done. I don't re-focus anything. I use f22 or if I think I need it, f32.

Am I supposed to first find both the near as well as the far focus points with the bellows so I can adjust to the center for best DOF after I do the tilt?

 

[Doremus Scudder]

Asymmetrical tilts make no difference, really. How you apply the tilt doesn't really matter. Once you have the tilt applied, the plane of sharp focus is no longer perpendicular to the lens axis (or parallel to the camera back, however you want to describe it). It's at some other angle. You have to imagine where it is by using the two points you used to apply the tilt. In your case, its the "far distance point," as you describe it and some foreground point that comes into sharp focus when you apply the tilt (see, you really are focusing more than once to apply the tilt; once with the focusing knob on the distant point and once more on a nearer object by applying the tilt).

So, you visualize your PoSF and see what objects or areas do not lie in it, on either side of it. Then you trial focus those objects or areas to find the two which are optically farthest from the PoSF, one on either side by using the focus knob. ("optically farthest" here means "with the most focus spread between them"; they may both be close to the camera position or not).

Then you simply place the focus halfway between the two extremes on the camera bed/rail, using the focus knob, and use the total focus spread distance to determine your optimum f-stop.

Does that help?

Doremus

 

[Alan Edward Klein]

Asymmetrical tilts make no difference, really. How you apply the tilt doesn't really matter. Once you have the tilt applied, the plane of sharp focus is no longer perpendicular to the lens axis (or parallel to the camera back, however you want to describe it). It's at some other angle. You have to imagine where it is by using the two points you used to apply the tilt. In your case, its the "far distance point," as you describe it and some foreground point that comes into sharp focus when you apply the tilt (see, you really are focusing more than once to apply the tilt; once with the focusing knob on the distant point and once more on a nearer object by applying the tilt).

So, you visualize your PoSF and see what objects or areas do not lie in it, on either side of it. Then you trial focus those objects or areas to find the two which are optically farthest from the PoSF, one on either side by using the focus knob. ("optically farthest" here means "with the most focus spread between them"; they may both be close to the camera position or not).

Then you simply place the focus halfway between the two extremes on the camera bed/rail, using the focus knob, and use the total focus spread distance to determine your optimum f-stop.

Does that help?

Doremus

Let's take my picture that we discussed before.
1. Where would you focus far initially and where to set the near tilt.
2. Where would the two areas where the farthest from the PoSF be that you would try to focus at to determine then the halfway focus point?


(So, you visualize your PoSF and see what objects or areas do not lie in it, on either side of it. Then you trial focus those objects or areas to find the two which are optically farthest from the PoSF, one on either side by using the focus knob. ("optically farthest" here means "with the most focus spread between them"; they may both be close to the camera position or not).

Then you simply place the focus halfway between the two extremes on the camera bed/rail, using the focus knob, and use the total focus spread distance to determine your optimum f-stop.)

 

[Vaughn]

Keep the back vertical. Place focus at about where you wrote "Near tilt for focus choice #1. Add a little forward front tilt to get the fence close to being in focus. This should also bring the tree top more into focus. Then reduce the aperture until the fence and the building (not just the tree top) come into sharp focus, close another stop for good luck and take the photo.

But I would also be keeping an eye on the dirt behind the fence -- which is why I would not tilt until the fence is totally sharp -- I'd let the smaller aperture bring both the fence and the dirt behind it into sharpness.

My system: Reduce the aperture until the fence and the top of the tree come into sharp focus. If they do not come into focus at the same time, adjust the bellows in or out until they do. Adjust amount of swing if needed.

Otherwise, close is the fence, focus on it and mark the place on your rail, focus on the building (effectively infinity...or use the clouds), using the same standard, move your standard to the point halfway between there and where you first marked the rail. Again, just know that you have both close and near-mid-focus in the forground (fence and dirt seen behind it) that you need to deal with.

 

[Chuck_P]

Here's the photograph I made that references my OP. This image is sharper than I would have thought it would've been. The foreground tree is definitely taller than my far focus point, which was the right side chimneys of the building, my near focus point was a spot on the ground some distance in front of the camera. Now, I did not consider a "focus spread" that Doremus has been alluding to. I need to investigate that process. I stopped down to f/22. On the negative, under a loupe, I'm very pleased with the overall focus, especially the tops of the foreground tree. I suspect f/22 helped to overcome any actual focus inaccuracy............I'm interested in Doremus' thoughts on it.

Edit: I don't understand why the focus when uploaded is softer than the focus when not uploaded, but that is definitely the case, at least on my screen.

 

[Doremus Scudder]

Alan and Chuck,

In both your cases, I would first set up the camera level and plumb and frame the image with rise if needed.

Chuck, in your case you mentioned you swung back and front standards parallel to the façade to prevent horizontal convergence, which is the same as setting up the camera parallel to the façade in the first place and using shift. I may have done that as well; your result is very nice. At any rate, that is also just framing the image, just like using rise only 90° transposed.

Now, if I felt I needed tilt to help get more things closer to the plane of sharp focus, I would have simply chosen the obvious "near" points for my tilt reference points for both your images. These would be for you Chuck, the closest grass at the very bottom of your image and the very top branches of the tree. For you, Alan, they would be the top of the tallest fence post in the foreground and, also, the top branches of the tree.

Then I would apply front tilt till both these reference points were sharp. (Alan, I know you love your asymmetrical rear tilt, but moving the back away from plumb when photographing architecture results in converging vertical lines that are parallel in the scene. That's fine if that's what you want, but if you don't, you have to use front tilt, which doesn't affect the rendering of the image.)

Using the obvious "near" points for setting the tilt combines the tilt with finding the near focus position (I'll talk more about focus spread later). Once you have the tilt reference points in focus, the camera is also focused on the "near." You can then note the position of focus on the camera bed/rail and then you just need to find the position for the "far."

This is where you need to be aware that something in the foreground that is farthest from the tilt reference point at the bottom of the image might end up being the "far" focus point, even though it is physically closer to the camera. Chuck, in your image, there's nothing below the lawn, so you'd look at the base of the building at it's greatest distance from you and the clouds at the right side of the image and see which one gave you the greatest focus spread (more later).

Alan, in your image there is a lot of distance between the top of the fence posts and the ground directly below it.
Therefore, the focus spread between the fence-post top and the surface of the ground might well end up being the greatest in the scene. Yes, I know that the ground below the fence posts is not, literally speaking, "far" from the camera, but, after you have tilted the plane of sharp and focused on the top of the fence post, the ground is now below it, making it, optically speaking, in the "far" category. (remember, when you tilt the PoSF, we often have to think in terms of "above = near" and "below = far"). And, since the depth of field is shallowest closer to the camera, there may be more difference in bellows draw between the top of the fence post and the ground below it than between any other two objects in the scene. But, you need to check to make sure, so take a look at other things, like where the ground meets the far horizon, or the distant clouds and see which on actually gives you the greatest change in bellows draw. Once you've found that point, it's your "far" position.

So, after all this and in both your cases, you'd note the position of whichever point gave you the largest focus spread and then use that and your initial tilt position as the boundaries of your focus spread. Then you place focus at the halfway point and choose an aperture.

************************************************

Chuck, let me address in more detail the method I use to focus and select the optimum f-stop so that my references to "focus spread" become clearer. (Alan is familiar with my method already, since we've discussed about it in the past.)

I use a method for selecting the aperture that uses the distance of the focus spread to determine the optimum f-stop. I learned it from the LF home page article on "How to select the f-stop" here: https://www.largeformatphotography.info/fstop.html . The object is to optimize the two variables of out-of-focus and diffraction degradation from using very small apertures. The article goes into circles of confusion and airy disks, etc., etc. It's well-worth the read, but you can get a quick start on the method by simply applying the method and using the table for focus spreads and corresponding f-stops that is provided. I'll summarize it quickly:

First, you determine the "nearest" and "farthest" things you want to be in sharp focus in the final print. (The above is all about finding those points when tilt is applied; when the camera is in zero position, it's rather straightforward.) Then you note the position on the camera bed/rail of these two points and determine the distance between them (in mm). This is your focus spread (i.e., nothing to do with distance between objects in the scene). You'll need a mm scale on your camera rail or bed for this. I use wooden folders with mm scales printed out on self-adhesive labels and applied to the camera bed along with a couple of lines on the moving part of the bed for reference marks.

After you have the focus spread, there are two more steps. You first position your reference mark halfway between the two extremes on the camera bed/rail. This is the proper focus point (you don't have to check ground glass at all, but you can if you like, just to see where the focus in the scene ends up). Then you select the optimum f-stop from a table. It's easy to use the table that the author of the above-mentioned article supplies. It's based on a 0.2mm circle of confusion/airy disk in the final print at about a 7x enlargement (8x10 from 35mm or 28x35-inch from 4x5, so it's really good for 16x20s and smaller from 4x5). Here's the table for convenience:

Table of optimal f-stops​

This shows you the best value of the f-stop to use. for a given focus spread in mm.
D = focus spread in mm. F = f-stop given in decimal values (e.g., 16.6 = f/16 plus 2/3 more, or f/22 and 1/3 less)

D ---- F
1 --- 16.6
2 --- 22.6
3 --- 32.2
4 --- 32.6
5 --- 32.9
6 --- 45.2
7 --- 45.4
8 --- 45.6
9 --- 45.8
10 -- 64

So, to summarize:
1. Choose near and far focus points after composing the image and applying movements (when tilting or swinging, keep in mind that "near" and "far" are not always what they seem).
2. Note the positions on the camera bed/rail for the two focus points.
3. Position the bellows draw / camera focus (whatever you want to call it) at the halfway point on the camera bed/rail between the two extremes of near and far.
4. Choose the optimum f-stop from the table.

Note that you don't ever have to squint at a dark, stopped down image and try to guess if what you want is going to be in sharp focus.

Certainly, there's more than one way to do all of this. Vaughn has great success with his methods. I find this method to suit my needs really well. Often, it's quite difficult for me to get a good view of the entire ground glass, much less spend time with my loupe and a dark, stopped-down image trying to determine if this or that is in sharp enough focus. This method takes the guesswork out of it and has worked superbly for me for years.

Hope this helps,

Doremus

 

[Alan Edward Klein]

Alan and Chuck,

In both your cases, I would first set up the camera level and plumb and frame the image with rise if needed.

Chuck, in your case you mentioned you swung back and front standards parallel to the façade to prevent horizontal convergence, which is the same as setting up the camera parallel to the façade in the first place and using shift. I may have done that as well; your result is very nice. At any rate, that is also just framing the image, just like using rise only 90° transposed.

Now, if I felt I needed tilt to help get more things closer to the plane of sharp focus, I would have simply chosen the obvious "near" points for my tilt reference points for both your images. These would be for you Chuck, the closest grass at the very bottom of your image and the very top branches of the tree. For you, Alan, they would be the top of the tallest fence post in the foreground and, also, the top branches of the tree.

Then I would apply front tilt till both these reference points were sharp. (Alan, I know you love your asymmetrical rear tilt, but moving the back away from plumb when photographing architecture results in converging vertical lines that are parallel in the scene. That's fine if that's what you want, but if you don't, you have to use front tilt, which doesn't affect the rendering of the image.)

Using the obvious "near" points for setting the tilt combines the tilt with finding the near focus position (I'll talk more about focus spread later). Once you have the tilt reference points in focus, the camera is also focused on the "near." You can then note the position of focus on the camera bed/rail and then you just need to find the position for the "far."

This is where you need to be aware that something in the foreground that is farthest from the tilt reference point at the bottom of the image might end up being the "far" focus point, even though it is physically closer to the camera. Chuck, in your image, there's nothing below the lawn, so you'd look at the base of the building at it's greatest distance from you and the clouds at the right side of the image and see which one gave you the greatest focus spread (more later).

Alan, in your image there is a lot of distance between the top of the fence posts and the ground directly below it.
Therefore, the focus spread between the fence-post top and the surface of the ground might well end up being the greatest in the scene. Yes, I know that the ground below the fence posts is not, literally speaking, "far" from the camera, but, after you have tilted the plane of sharp and focused on the top of the fence post, the ground is now below it, making it, optically speaking, in the "far" category. (remember, when you tilt the PoSF, we often have to think in terms of "above = near" and "below = far"). And, since the depth of field is shallowest closer to the camera, there may be more difference in bellows draw between the top of the fence post and the ground below it than between any other two objects in the scene. But, you need to check to make sure, so take a look at other things, like where the ground meets the far horizon, or the distant clouds and see which on actually gives you the greatest change in bellows draw. Once you've found that point, it's your "far" position.

So, after all this and in both your cases, you'd note the position of whichever point gave you the largest focus spread and then use that and your initial tilt position as the boundaries of your focus spread. Then you place focus at the halfway point and choose an aperture.

************************************************

Chuck, let me address in more detail the method I use to focus and select the optimum f-stop so that my references to "focus spread" become clearer. (Alan is familiar with my method already, since we've discussed about it in the past.)

I use a method for selecting the aperture that uses the distance of the focus spread to determine the optimum f-stop. I learned it from the LF home page article on "How to select the f-stop" here: https://www.largeformatphotography.info/fstop.html . The object is to optimize the two variables of out-of-focus and diffraction degradation from using very small apertures. The article goes into circles of confusion and airy disks, etc., etc. It's well-worth the read, but you can get a quick start on the method by simply applying the method and using the table for focus spreads and corresponding f-stops that is provided. I'll summarize it quickly:

First, you determine the "nearest" and "farthest" things you want to be in sharp focus in the final print. (The above is all about finding those points when tilt is applied; when the camera is in zero position, it's rather straightforward.) Then you note the position on the camera bed/rail of these two points and determine the distance between them (in mm). This is your focus spread (i.e., nothing to do with distance between objects in the scene). You'll need a mm scale on your camera rail or bed for this. I use wooden folders with mm scales printed out on self-adhesive labels and applied to the camera bed along with a couple of lines on the moving part of the bed for reference marks.

After you have the focus spread, there are two more steps. You first position your reference mark halfway between the two extremes on the camera bed/rail. This is the proper focus point (you don't have to check ground glass at all, but you can if you like, just to see where the focus in the scene ends up). Then you select the optimum f-stop from a table. It's easy to use the table that the author of the above-mentioned article supplies. It's based on a 0.2mm circle of confusion/airy disk in the final print at about a 7x enlargement (8x10 from 35mm or 28x35-inch from 4x5, so it's really good for 16x20s and smaller from 4x5). Here's the table for convenience:

Table of optimal f-stops​

This shows you the best value of the f-stop to use. for a given focus spread in mm.
D = focus spread in mm. F = f-stop given in decimal values (e.g., 16.6 = f/16 plus 2/3 more, or f/22 and 1/3 less)

D ---- F
1 --- 16.6
2 --- 22.6
3 --- 32.2
4 --- 32.6
5 --- 32.9
6 --- 45.2
7 --- 45.4
8 --- 45.6
9 --- 45.8
10 -- 64

So, to summarize:
1. Choose near and far focus points after composing the image and applying movements (when tilting or swinging, keep in mind that "near" and "far" are not always what they seem).
2. Note the positions on the camera bed/rail for the two focus points.
3. Position the bellows draw / camera focus (whatever you want to call it) at the halfway point on the camera bed/rail between the two extremes of near and far.
4. Choose the optimum f-stop from the table.

Note that you don't ever have to squint at a dark, stopped down image and try to guess if what you want is going to be in sharp focus.

Certainly, there's more than one way to do all of this. Vaughn has great success with his methods. I find this method to suit my needs really well. Often, it's quite difficult for me to get a good view of the entire ground glass, much less spend time with my loupe and a dark, stopped-down image trying to determine if this or that is in sharp enough focus. This method takes the guesswork out of it and has worked superbly for me for years.

Hope this helps,

Doremus

But I only focus the bellows once. That's the whole point of asymmetrical tilting. There is no second focus point with the bellows. You tilt back the back standard to get the near point in focus after you focus the far point with the bellows. Are you saying I have to check other focus points with additional bellows adjustments beside the first and only one I do now?