Focusing the View Camera

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Wayne
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I thought that tilting the front standard forward would bring the whole scene into sharp focus front to back but it didnt, it shifted focus to the front or back but didn't bring everything together.

What am I doing wrong this time ?
 
Envision that the plane of focus is like a book... it has a height, a width, and thickness (depth). Say it starts out as full image height/width and 3 ft deep. When you tilt the front standard (or image plane) the "book" leans with it. So it doesn't cover full height anymore unless the depth was very large. And to further complicate things, what was a fixed depth now becomes a wedge shape (shallower nearer to the camera).
 
Envision that the plane of focus is like a book... it has a height, a width, and thickness (depth). Say it starts out as full image height/width and 3 ft deep. When you tilt the front standard (or image plane) the "book" leans with it. So it doesn't cover full height anymore unless the depth was very large. And to further complicate things, what was a fixed depth now becomes a wedge shape (shallower nearer to the camera).

Well how do you get everything in focus, rock in the foreground to sweeping mountain range? it must be possible there are lots pictures that are incredibly sharp everywhere.
 
It doesn't and can't increase or decrease the dof, all that tilt or swing of the front standard can do is to shift the plane of sharp focus.

It isn't complicated in terms of the physics, if it's a subject that appeals to you then just do some research on Scheimpflug and all will be revealed - this one is a starting point but is a bit basic - https://en.wikipedia.org/wiki/Scheimpflug_principle
The links at the bottom of the page are useful.

But, if you're the practical type who doesn't like equations, just experiment, all you need is a black cloth, the lens wide open and a bright light. And, when you've done that, set everything back to their starting positions and repeat, this time using the rear standard movements.

You really understand it now? Good. Now start again, using both standards both together and in opposition, it now gets really interesting, and useful :)
 
Well how do you get everything in focus, rock in the foreground to sweeping mountain range? it must be possible there are lots pictures that are incredibly sharp everywhere.
Practice, and understanding what is happening when you tilt or swing the front or/and the rear standards of the camera to the "plane" of focus and the shape of the "area" of focus.

It really isn't easy.

I have no idea if this video is any good, but watching someone actually using tilt and swing might kick-start getting the hang of it. His videos tend to be useful, but I haven't watched this one.

View: https://www.youtube.com/watch?v=SEo-zXOzEBQ
 
It doesn't and can't increase or decrease the dof, all that tilt or swing of the front standard can do is to shift the plane of sharp focus.

It isn't complicated in terms of the physics, if it's a subject that appeals to you then just do some research on Scheimpflug and all will be revealed - this one is a starting point but is a bit basic - https://en.wikipedia.org/wiki/Scheimpflug_principle
The links at the bottom of the page are useful.

But, if you're the practical type who doesn't like equations, just experiment, all you need is a black cloth, the lens wide open and a bright light. And, when you've done that, set everything back to their starting positions and repeat, this time using the rear standard movements.

You really understand it now? Good. Now start again, using both standards both together and in opposition, it now gets really interesting, and useful :)
I dont really "get" the experiment Garry, sorry
 
A much simpler solution is to just stick with smaller film or sensor formats, which use shorter focal lengths, which in turn give greater depth of field for a given stop. :coat:
 
OK. The frustrating thing here is that, if we were together with a monorail camera and a suitable subject you'd completely get it after about 5 minutes:)

So, let's just cover the absolute basics. You say that you have a monorail camera, and if you do then it will have shift up, shift down, shift left, shift right, tilt up, tilt down, swing right and swing front on the front standard (where the lens goes), and all of these movements will be on the rear standard (where the film goes) too.

Non-monorail cameras are likely to have less movements, technical cameras are a step down and field cameras are two steps down.

  1. Start off with both cameras set to their default positions, i.e. everything dead square, just like any other camera, and completely forget about all of the movements on the rear standard.
  2. Turning now to the front standard, forget about the shift movements. Leave them in the default positions, they're incredibly useful but not relevant to this "experiment" because all that they do is to move the image left, right, up or down, and that isn't what we want to do here
  3. That leaves us with just the tilt movements, you can swing the lens to the left or the right on one control, and you can tilt the lens up or down with the other control. They do the same thing, but to keep it simple we're going to start with just the up/down tilt.
  4. You need a subject that's easier if fairly small, and that has some depth and a clear, basic shape. A cornflake packet is ideal.
  5. For this purpose, the camera will need to be at a bit of an angle, pointing down. Well, it doesn't need to be at all, that's what falling front is for, but we're keeping it simple.
  6. Focus about halfway into the subject. The bit you're focused on will be sharp, just like any other camera, and the nearer and further parts will be blurred, as you would expect. If possible, stick a ruler on top of the subject, going from front to back - not essential but it will give you good data that doesn't rely on your own judgement.
  7. Now tilt the lens downwards, try different amounts of tilt until it's perfectly sharp, front to back. Depending on various things, you may need to adjust the camera height, but that doesn't matter, and you may need to re-focus, depending on your camera model.
  8. You've now nailed it, you have exactly the same dof as before but you've tilted the plane of sharp focus so that the bit that matters in this shot, is perfectly sharp, front to back. Something else will be out of focus but the out-of-focus bit will either be out of shot or can be corrected with a different movement.
  9. In practical (but not in theoretical terms) you've got sharp focus front to back, but you can also achieve the opposite effect, so now you tilt the lens upwards instead of downwards, and you can, if you wish, have just a tiny part of the cornflake packet in sharp focus.
  10. That's it, job done. Repeat the experiment with the swing movements, both of which will increase or decrease the plane of sharp focus left to right instead of front to back, and of course you can (and eventually will) learn to combine both tilt and swing, for pretty incredible results. And, of course, you can and should also use drop front, to square up the image and avoid perspective distortion, or to increase it, and every one of these movements can be combined, and often are.
Just to complicate things, once you've mastered the front standard movements, repeat the process with the front standard in the "normal" settings and make the adjustments to the rear standard. The tilt and swing on the rear standard will also change the shape of the subject

And then do both together, for really incredible results. Everyone will say that you used AI, but you'll know better:) Does this help?
 
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