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View Full Version : Rear Tilt - What am I Doing Wrong?



Don Homewood
15-Apr-2016, 11:54
I'm still new to LF photography (just shy of 6 months in) and I've become decently familiar with most the movements my camera is capable of, but still haven't really tried out tilting the rear standard. From what I understand, rear tilt distorts the image on the groundglass which can be used to enlarge/reduce elements in the foreground/background, but I can't seem to get it to work. The (in this case foreground) object stays the same size.

I'll compose the image, focus on the foreground object, tilt the rear standard back, and then refocus. I can't see a difference. My groundglass has a grid so I can directly compare the size of the object before and after the tilt. If the object takes up a 5x3 area on the grid before the tilt, it takes up the same area after the tilt as well.

I'm sure the problem is with my technique and not elsewhere. But, unlike with front standard tilt, I can't seem to find any good tutorials online/in books/etc. describing the steps of the process. :confused:

mdarnton
15-Apr-2016, 12:10
The best place to see the effect of rear movements is on rectangular things such as buildings. Take your camera out and aim it upwards to include a building's top. Then tilt the back so that the building is not smaller at the top. This will happen when the back is vertical like the building front. This will be very clear as you tilt the back because you are especially sensitive to things being nice and neatly square and parallel. Then tilt the front of the camera so that it is also vertical, and this will bring the top and bottom of the building into focus. That's the basic move. Same for sideways, looking sideways at something.

There are other, easier, ways to accomplish the same thing (a simple front rise, in the building's case). You won't see much effect in landscapes and things without rectangular shapes, even though the effect will be there, just the same. If you're counting on grotesque changes, no, that isn't going to happen much.

Bob Salomon
15-Apr-2016, 12:16
Rear tilts and swings change the shape of an object. Best way to see this is compose a building and then do front tilts to control Scheimpflug. Take a picture. Now recompose and use rear tilts to control Scheimpflug.

If you had set up and composed the front tilt shot properly, so that the camera's back was perpendicular to the building then the vertical lines of the house are straight and parallel to each other.
On the other hand, with the second shot, the back was not perpendicular to the building and now the vertical lines of the house are no longer straight and parallel to each other and they now keystone. That is one way the back movements change the shape of the object.

Don Homewood
15-Apr-2016, 12:25
You won't see much effect in landscapes and things without rectangular shapes, even though the effect will be there, just the same. If you're counting on grotesque changes, no, that isn't going to happen much.

Interesting. The way some people talk about it online makes it sound like you can make even the tiniest foreground elements take up a large portion of the composition. (See here for an example: https://www.onlandscape.co.uk/2013/03/the-art-of-looming/)

EDIT: So I'm guessing the image in that article was just made with the usual "get-low-and-close-with-a-wide-lens" technique?

Kevin Crisp
15-Apr-2016, 12:43
Most movements can be subtle and get the job done. But that makes explaining it harder so people do often go with extreme examples to get the point across. In many landscape situations just a little rear tilt, or front tilt of the lens, will work wonders on getting near and far in focus, or at least close enough once you stop down.

Peter Gomena
15-Apr-2016, 12:58
Make a simple tabletop setup with a round object on it, like a small rubber ball. If you focus with rear tilt, the ball becomes an oval. If you focus with front tilts, it stays round as long as the back is perpendicular to the rail.

AtlantaTerry
15-Apr-2016, 12:59
Don,

Did you miss this part of the above linked article?

Ignore the extra rise on the rear standard and just look at the overall relationship and you'll see that effectively we've used drop front and front tilt. This explains one of the reasons why looming works...

So, evidently, you would be not be working with back movements as much as you believe.

Also, in the beach example, the photographer used a very wide angle 20mm tilt shift lens on a DSLR.
I'm not sure, but in 4x5" terms this might be something like using a 75mm lens.
(I know if I'm wrong I will be corrected.:))
A bag bellows would be a very useful tool with such a wide angle lens.

Bob Salomon
15-Apr-2016, 13:12
Interesting. The way some people talk about it online makes it sound like you can make even the tiniest foreground elements take up a large portion of the composition. (See here for an example: https://www.onlandscape.co.uk/2013/03/the-art-of-looming/)

EDIT: So I'm guessing the image in that article was just made with the usual "get-low-and-close-with-a-wide-lens" technique?

Those two pictures were not taken with the same focal length lens, so it really isn't a good comparison.

Alan9940
15-Apr-2016, 13:17
Hi Don,

Tilting the back standard backward (talking landscapes here) will cause close foreground elements to "loom" larger; in my experience (30+ years of LF work), this isn't something you can see on the groundglass. If you want to actually see the effect, compose an outdoor scene with boulders/rocks/etc in the close foreground, focus, etc, take picture. Move rear standard back to its normal position, ensure that foreground elements are in focus, take picture. Print both of these shots and you should notice the effect from tilting the rear standard rearward.

On a side note...not that you asked... :) If your camera has base tilts on the rear standard and you plan to tilt the rear standard rearward, an easy way to achieve proper focus is to: 1) focus on the most distant area, 2) then, as you tilt the rear standard rearward keep an eye on that distant area and turn the focus knob to keep that area in focus until the foreground is sharp. That's it! Simple and works beautifully. Of course, you may have to adjust the focus plane depending on the scene.

Have fun!

Don Homewood
15-Apr-2016, 13:52
Don,

Did you miss this part of the above linked article?

Ignore the extra rise on the rear standard and just look at the overall relationship and you'll see that effectively we've used drop front and front tilt. This explains one of the reasons why looming works...

So, evidently, you would be not be working with back movements as much as you believe.

I read that paragraph several times yesterday and I could make no sense of it. But re-reading it now at your suggestion it made a little sense. I just tried it and, with a little fall and a good amount of forward tilt on the lens, I could see a difference from before to after. Not much of one, but it was there.

I guess my question now is, if the same effect can be accomplished with the front standard why is it always suggested to do it with the back? Is it because you might run out of image circle doing it with the front?


Hi Don,

Tilting the back standard backward (talking landscapes here) will cause close foreground elements to "loom" larger; in my experience (30+ years of LF work), this isn't something you can see on the groundglass. If you want to actually see the effect, compose an outdoor scene with boulders/rocks/etc in the close foreground, focus, etc, take picture. Move rear standard back to its normal position, ensure that foreground elements are in focus, take picture. Print both of these shots and you should notice the effect from tilting the rear standard rearward.


This thought actually did cross my mind and I was planning on doing this exact experiment next time I was out.

Thanks to all of you for your help. :)

Maris Rusis
15-Apr-2016, 17:03
With base tilts the "rule" is focus for the FAR (the bottom of the ground glass) then tilt for the NEAR (the top of the ground glass). After the first try the FAR will probably need a bit of re-focus. Then the NEAR will probably need a small tilt adjustment. Just repeat the sequence with smaller and smaller adjustments until NEAR and FAR are both sharp.

With centre tilts I focus on the FAR and NEAR and note the change in extension and then set the focussing standard half way. Then tilt until the FAR comes sharp and the NEAR should be sharp too. Some minor tweaks to focus and tilt may be needed.

David Lobato
15-Apr-2016, 21:37
When I was new with 4x5 I read something that Fred Picker wrote about foreground objects appearing larger with back tilt. So I set up a scene and made Polaroid shots with rear tilt, then with front tilt. I used a monorail 4x5 camera with a 210mm lens. It took the side by side comparison to see for myself, and it does happen. If I could ever find those Polaroids lost in old boxes I'd post scans of them.

Then with the camera tilts zeroed, I made shots of round objects at the edges of the image circle, and the edges of the frame, using large amounts of shift. Round objects took on egg shapes in the Polaroids. I had read about that as well. These exercises have helped me a lot for shooting LF photos. I think the OP was wanting a similar lesson on using back tilt.

Doremus Scudder
16-Apr-2016, 01:43
Don,

Despite what a couple of people here have said, the effect of tilting the back is easy to see on the ground glass. It may not be as much as you are expecting, but, basically, the ground glass is WYSIWYG.

The effects of tilting are familiar to anyone who uses a projector for presentations. The farther the screen is from the projector, the larger the image will be. And, if the screen is not perpendicular to the line of projection, there will be keystoning, because one part of the screen is farther from the projector than another. Modern digital projectors have keystoning correction built in, but the old-fashioned way of fixing this was to tilt the screen so it was perpendicular to the line of projection.

Think of it this way: With a camera, the subject and lens together constitute the projector; the ground glass is the screen. The lens is projecting an image of the subject onto the screen, which is the ground glass. The projection comes from the lens in the shape of a cone; i.e., the closer the ground glass is to the lens, the smaller the image circle and vice-versa. So, the farther the ground glass is from the lens (i.e., the farther the screen is from the projector), the larger the image will be. This is intuitive if you've used projectors and screens much.

Now, mentally take your screen (i.e., the ground glass) and tilt it. You can easily see that when you do, the top gets closer or farther from the lens relative to the bottom. The projected image will be relatively larger for the part of the screen that is more distant from the lens and vice-versa.

Back to practicality. You set up your camera for a scene with some both foreground and distant elements in the same plane. Leave everything in zero position and frame and focus your shot. Now, ignoring focus make some rather aggressive tilts, forward and backward with the back, and observe the image on the ground glass. Sure, the top and bottom of the image will go in and out of focus, but note that the size will change. This is pretty evident. In practice, one can often do this to choose a size relationship (to a certain extent) between near and far elements of a scene and then correct the focus by tilting the lens stage in the opposite direction. Play with your camera a bit with a shortish lens and some scenes with near/far elements on the same plane (e.g., the flat ground) and you'll see right away what I'm talking about.

Best,

Doremus

Noah A
16-Apr-2016, 08:50
I guess my question now is, if the same effect can be accomplished with the front standard why is it always suggested to do it with the back? Is it because you might run out of image circle doing it with the front?

An important thing to understand is that front swings and tilts only affect the plane of focus, while rear tilts and swings affect both the plane of focus as well as the shape of the image.

So using front tilt won't really exaggerate (or minimize) the size of the the foreground subject, but what front tilt can do is allow you to get that foreground object in sharp focus while keeping focus on the background as well. You're correct that rear tilts are what you want if you wish to change the shape of the objects or their apparent spacial relationships within the frame.

You can certainly see the results of tilting on the groundglass, though perhaps it's not as dramatic as you had hoped. In the initial scenario you described, you may not have noticed the foreground object getting larger, but perhaps the background got a bit smaller? That is visible but it can be harder to notice on the groundglass.

The difference between base and axis tilts has been mentioned earlier, one easy thing to remember is that objects near the tilt axis don't change much. So for example, if your camera has axis tilts and the object in the foreground aligns closely with your tilt axis, it won't change much. But objects in front of it and in back of it will change.

You'll generally notice more dramatic effects with wider lenses, which even with no movements tend to exaggerate the size of foreground objects.

While I understand it, that linked article isn't that clear and it could be adding to your confusion. I get the feeling it was intended to appeal to DSLR users with T/S lenses. The photos at the end are misleading, since it looks like a different lens was used for the 'tilted' example and also the camera position has changed. You still need to get close to your subject to get the 'looming' effect you're looking for.

Also, the camera movement examples are confusing. The first camera photo with the tilted back will get you the look you want.

The second photo is just a different way to accomplish the same thing. If your camera doesn't have rear tilt, such as a DSLR with a T/S lens, you can tilt the entire camera rearwards. That action alone gets you the shape change you're looking for. The lens drop is just used to get the framing you want and the tilt is used to get the focal plane you want.

And of course, rise, fall and shifts control the framing or composition of the photo.

The position of the camera's rail or bed really is irrelevant. When the camera back is perfectly vertical (plumb), the perspective will appear natural. Tilting it will change the shape, it doesn't matter which camera movements you use to accomplish that tilt. They're all ways to accomplish the same thing. Again, front tilt controls only focus, rear tilt controls focus as well as shape.

The third camera photo in the article is misleading. If you set up the camera that way, you'll change the plane of focus but not the shape of the image since the back is vertical.

MAubrey
16-Apr-2016, 09:45
I guess my question now is, if the same effect can be accomplished with the front standard why is it always suggested to do it with the back? Is it because you might run out of image circle doing it with the front?

Well, the image circle can play a part, depending on the lens and the image format. But much of it is efficiency of movement. To replicate it with front movements, they had to use both tilt and raising...AND hand to adjust the angle of the entire camera sitting on the tripod in order to get a comparable camera position. Its much easier to have a level tripod from the beginning and just tilt the back.

Going back and reading Ansel Adam's The Camera might be worthwhile. His discussion of movements is very practical.

mdarnton
16-Apr-2016, 10:30
I think that people get in the habit of thinking of front movements for focus adjustment, and back ones for image proportions. I don't mean they do this invariably, but as a starting point, it's a convenient model because projection distance from the lens affects image size, and tilting the back is the most direct way to change the proportions of the image across the length or width of the film. You can do the same moves in many different ways, of course, and it's interesting to map out a relationship between front and back, and subject, and think of all the possible ways to get there and the ramifications of that.

I've been personally fascinated by the order that movements were developed. For instance, the earliest cameras, and simple portrait cameras also, didn't have front swings and tilts, only back. On portraits, that means to bring both eyes into focus when one is farther, moving the back for that exaggerates foreshortening, making the near cheek, too large already, larger. You'd think they'd have figured that out and immediately gone for front movements, but nope.

MAubrey
16-Apr-2016, 13:00
I've been personally fascinated by the order that movements were developed. For instance, the earliest cameras, and simple portrait cameras also, didn't have front swings and tilts, only back. On portraits, that means to bring both eyes into focus when one is farther, moving the back for that exaggerates foreshortening, making the near cheek, too large already, larger. You'd think they'd have figured that out and immediately gone for front movements, but nope.

Perhaps image circle was the limiting factor? If you're working with a normal FL tessar, for example, your image circle is already going to constrain how much you can do with front movements, whereas back swings and tilts all stay within the image circle.

David Lobato
16-Apr-2016, 13:05
Here's a real situation with back tilt. Sometime ago I read that Ansel Adams' Mount Williamson, Sierra Nevada from Manzanar, California c. 1944 used back tilt to emphasize the foreground rocks. But reading articles on it now say that he tilted the camera forward, then tilted the back to get the right focus plane for his composition. It may be possible Adams did want the near rocks to loom larger. This may also explain why some photographers trying to re-create the scene (presumably some with, and some without, back tilt) have differing opinions on the exact location, including the camera height above the ground, of his photo.

This effect may have been unavoidable due to the lack of front tilt on wooden 8x10 cameras of that time.

Robert Tilden
16-Apr-2016, 13:12
Regarding the images you linked to, you're right in that "get-low-and-close-with-a-wide-lens" was used. You can see that the perspective has changed by looking at the relative position of the grasses in the midground and the water line.

Kodachrome25
19-Apr-2016, 22:07
An important thing to understand is that front swings and tilts only affect the plane of focus, while rear tilts and swings affect both the plane of focus as well as the shape of the image.

Yes and no...

With using front tilts and swings only you are moving the lens projection angle in relation to the film plane and if the movements are significant enough, you can hit the edge of the image circle on the film area. With just rear tilts and swings you are moving the film plane around in the image circle so while you may be changing the size of objects relative to the end of the film that has moved the most, you are for the most part, in the center of the image circle if no front movements have been made.

I found this to be important to consider when I was just using front movements and sometimes it affected image sharpness. So now I use a combination of rear and front tilts and swings to both standards to arrive at optimal image quality.

It's made a big difference in overall image sharpness if more than average movements are required.