Scheimpflug Question

[John Hennessy]

To me a facinating point about Herr Theodor Scheimpflug and his rule is that (although I do not know this to be a fact) it must have serindipotous. The camera had long since been invented and had a bellows in order to be foldable and lighter. Was he the first to observe the inclined plane of sharp focus or were photographers aware of and exploiting the phenomina and Scheimpflug just set out to explain it? The Encyclopedia of Photography says nothing and I see nothing in Merklinger either. The answer probably can be found in the New York and London photography publications of the end of the 19th century.

[Ole Tjugen]

Herr Scheimpflug was trying to work out the optimal camera configuration for aerial surveillance...

The effect was known before: That a tilt of the lens allowed the plane of focus to extend along a plane from very near to infinity. Scheimpflug discovered the rule stating how much tilt was needed at a given elevation, surely a nice thing to know before taking your camera up in a balloon near the front line!

Merklinger's rule is useful for working out the other way: Where will the focus plane be at a given tilt? I find Scheimpflug to be more than sufficient in normal field use, since I rarely pre-focus and pre-tilt the camera before taking it out in the field. If it's sharp, it's in focus; if not, I'll have to adjust focus and/or tilt.

[John Hennessy]

<Herr Scheimpflug was trying to work out the optimal camera configuration for aerial surveillance...>

That jogs my memory: he was actually Hauptmann Scheimpflug. Military applications are occasionally useful to civilians!

By the way, I revealed a pro-English language prejudice in saying the New York and London photo journals would show this history. I should have included at least Berlin and Geneva and Oslo!

[Rob Barker]

Ernest - Your explanation has the benefit of simplicity, but it is not complete as there is another variable - the lens-film distance.

As Merklinger explains, the Scheimplflug principle (discovered, of course, by Charpentier) is not complete enough to be of practical use to us in the field. You need to use Merklinger's hinge rule (discovered, of course, by Scheimpflug..) to be able to predict the lens tilt angle required with any accuracy.

The links to Merklinger's work above are must-reads in my humble opinion, and his book isn't that hard if you get your teeth into it. The "addendum" on the website is an accessible and useful summary.

[Ken Burns]

An important follow-up question: Does anyone know how to correctly pronounce Scheimpflug?

[Ole Tjugen]

Pronouncing "Scheimpflug" is almost as easy as pronouncing my own name.

Anything is easy once you learn to speak the language

[Ellis Vener]

As Merklinger explains, the Scheimplflug principle (discovered, of course, by Charpentier) is not complete enough to be of practical use to us in the field.

Bunk & nonsense of course. A direct appliction of the S.P. works perfectly well in the field or the studio. It is either that or every image I and every photographer has made made utilizing the S.P. during the many decades before Dr. Merklinger wrote his pamplet is out of focus. I'm not saying that Merklinger is wrong -- or even that you are wrong as you have found a way of working that suits you -- just that the S.P. is fine for practical application without having to do his calculations.