AJSJones
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 p.1 #5 · Tilt angle table for TS lenses | |
skefford wrote:
Andy,
When using tilt, I don't shift the lens this way. I don't see much point in doing so either.When I tilt, I rotate about an axis running vertically, which I would imagine is the more usual case, especially for landscape.
Stevve
The diagram is a side view so the optical axis that is tilted would be vertical in a non-TS lens. If you want to keep the sensor vertical to avoid converging verticals, then shift (fall) is a good way to alter the composition to reduce e.g., the amount of sky and increase the amount of foreground in the picture. Not always needed, as you point out.
skefford wrote:
But even in your case, why does the Scheimpflug point have to be on the ground plane? And where is the plane of focus? This is the thing that matters. If the plane of focus does not form part of your equation, then I don't see what the point of it all is.
Stevve
The example is, as explained, specific for the case where the ground plane IS the plane of focus - thus the Scheimpflug line must be in that plane, as must the plane of the lens's vertical axis and the sensor plane - therefore , with the camera vertical, the line is under the camera, on the ground. If you don't use fall, but rather lower the camera to get the foreground to be more prominent, then you'll need more tilt - this table helps you find that angle if you measure (guess) the height, so you'll be close when you start to fine-tune.
In principle, you would only need to look through the viewfinder to compose. Then set the focus to infinity (or hyperfocal or user selected - based on the distance scale n the lens), measure the height, dial in the tilt and set the aperture - ideally you would have it all in focus (of course you would check).
I hope that clarifies what the point is
Andy
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