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Copyright © 1800 - 2070. All rights reserved.

Visit biografmuseet.dk about Danish cinemas

 

The Ethel O’Brien Printer
Letters from Walter P. Siegmund, 2006

Read more at
in70mm.com
The 70mm Newsletter
Written by: Walter Siegmund. Hand written letters retyped for in70mm.com by Brian Guckian, Ireland Date: 28.02.2015
Full circle image to show distortion in the Bug-Eye lens causing vertical lines to bend. Walter Siegmund to the left. Note the shadow of the camera lens on the ground to the right.

Brooklyn, CT, March 27, 2006

Hi Thomas,

Well, it is just over a year that we visited Bradford with you and it was a perfectly marvellous experience. You were so kind to make all the arrangements. We remember so many things with great fondness, meeting all the great people and the fantastic films, especially the beautiful print of “Oklahoma!” It does not seem possible that so many years have past since those hectic days in 1953-1955. What a wonderful exciting experience it was, and then to relive a portion of it fifty years later! Many, many thanks again.

It was sad that Brian did not join us but he refuses to fly in commercial aircraft (the safest mode of travel)! He would have enjoyed the nostalgia of it all.
 
More in 70mm reading:

Todd-AO's Distortion Correcting Printing Process

Walter Siegmund Interview

Todd-AO Home Page

Hollywood Comes to American Optical Co.

Walter P. Siegmund, a small bio

Walter Siegmund remembered


65mm Todd-AO Concept Tests

Internet link:

 
Distortion corrected image made with the Todd-AO "Bug Eye" lens. Walter Siegmund to the left.

Thomas, when I was moving some boxes of files from our old “Barn” the other day, I came across the enclosed “booklet” describing our detailed plans for printing "Oklahoma!" I thought you might like this for your collection. J Lions was one of our technicians (a photographer) and received a copy of the “bible”.

Preparation of Release Prints
Additional Printing Ideas
"Oklahoma!" Cue Sheet
"Oklahoma!" Printing Operation

Have fun reading all about it.

All the best,
Walt.
 
 
Distortion in the Bug-Eye lens causing vertical lines to bend.

Contact print from a “Bug-Eye” frame taken of a house somewhere either in New England or near Buffalo, New York.

Brooklyn, CT, May 8, 2006

Dear Thomas,

During our big move from Pomfret to Brooklyn (some 8 miles – 13km) many things were found which were long hidden and forgotten, including more old Todd-AO files and photos. I gave Brian copies of those items and I have enclosed two photos of possible interest.

American Optical Printing Lab
Behaviour of the SSC printer
CC Type Printer
Geometry of first steps
Definition of keystone formular
Case for x1,7 magnification
Calculations
Rectification Printing
 
All barn findings:

24_fps_Projection
Projection aperatures
MGM-65 (Panavision)
Cinemiracle
Todd-AO Patent Application

American Optial 1953
American Optial 1954

American Optical Printing Lab
Behaviour of the SSC printer
CC Type Printer
Geometry of first steps
Definition of keystone formular
Case for x1,7 magnification
Calculations
Rectification Printing

Preparation of Release Prints
Additional Printing Ideas
"Oklahoma!" Cue Sheet
"Oklahoma!" Printing Operation

Todd-AO Installation Procedure
Todd-AO Installation Procedure projection layout
Todd-AO Installation Procedure Pre-installation requirement

 
During the early days of Todd-AO correction printing the question arose regarding the distortion in the Bug-Eye lens causing vertical lines to bend. The horizontal curved lines were corrected by the deeply-curved screen and from the “best” viewing position, i.e. the centre of perspective near the front of the theatre. The vertical lines are not corrected unless some other step is taken.

Dr. O’Brien asked me to look into this problem along with the correction of the “droop” curvature we needed to correct for projection from the high booth. The latter is described in Dr. O’Brien’s patent, which you have. The correction of vertical lines resulted from a suggestion made by the first Mrs. O’Brien (Ethel D. O’Brien) who was a smart “technical” lady and often assisted her husband in his research. She said “why not curve the film in the other direction” according to Dr. O’Brien and he reported this to me.

Todd-AO Patent Application
Todd-AO Installation Procedure
Todd-AO Installation Procedure projection layout
Todd-AO Installation Procedure Pre-installation requirement

 
 
A “corrected” print which I may have made using my printing fixture - the “Ethel O’Brien Printer”, which we called the C-C printer.

So I had a fixture made and used a Leica camera lens to relay the image at about 1:1 from a curved negative to the print. [Drawing]

Enclosed is a contact print from a “Bug-Eye” frame (enlarged) taken of a house somewhere either in New England (or near Buffalo, New York)? The other is a “corrected” print which I may have made (who else?) using my printing fixture (the “Ethel O’Brien Printer”), which we also called the K-K printer (for reasons I can’t remember).

At one point in the overall development I recommended we use the K-K printer to correct vertical distortion in those scenes taken with the Bug-Eye (128˚) lens and possibly also the 64˚ lens but not needed for the 48˚ and 37˚ lenses, and then use the mirror anamorphic projection system (Delrama-derived) for the “droop”. All of which came just a little too late in the program, sadly, to say.

Anyway, that’s the story on the K-K correction. I am sending you the original fixture (without the Leica lens) for your collection. You can find such a lens in any good used camera store.

All the best,
Walt.
 
 
My printing fixture, the “Ethel O’Brien Printer”, which we called the C-C printer.

Brooklyn, CT, May 11, 2006


Dear Thomas,

You may find the enclosed material of further interest in connection with the printing of the Todd-AO “Process”. These are descriptions and original calculations on various ideas about corrective printing the release prints. The first printed pages are dated 8/10/53 (Aug 10) and some later printed pages done by George R Simpson (a great friend, office mate and skilled optical engineer) dated 9/3/53.

I assume, therefore, that all this material was produced in the late summer and fall of 1953. Many of the sketches and calculations are mine. For example, the sections titled “Calculations for case of concave object and image” and also “[?] of Keystone Formula”, but you see my handwriting has hardly changed in 50 years!
 
 
My printing fixture, the “Ethel O’Brien Printer”, which we called the C-C printer.

Anyway, I thought you might enjoy seeing these early notes and ideas on Todd-AO printing. Note also the printed section titled “Rectifications Required” written by Dr. O’Brien (B. O’B) himself. Many wonderful memories.

In my last letter I referred to the K-K printer. I don’t know why I thought K-K was the right designation but these notes refer to the C-C “printer” for the obvious reason that the negative and print are curved like 2 C’s. [Sketch]

Anyway forget the K-K. I have no idea why this came to me.

Also the thread on the printing (C-C) fixture is not a Leica thread mount. It is larger. Whether I used an adaptor or yet another lens I cannot recall. Still it is an original!

All the best,
Walt
 
 
   
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Updated 28-07-24