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Author Topic: Question about D150 "Curvulon" Correction Lens Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 08-03-2011 08:40 AM                        There was an auction on ebay for the D150 Curvulon attachment (Kollermorgan). There's a very cursory description which mentions that the lens elements are ground so that there is a focus variant of about 10ft between the center and the edges of the screen, correcting the focus for the curve across the screen. This seems to imply that the lens merely adjusts the focus to compensate for the distance difference between the left and right ends of the screen to the center. My understanding of what the Curvulon lens did was to correct for the geometric distortion that the curve introduces into the picture. With the lens, the bowing of horizontal lines at the top and bottom of the screen is mostly eliminated and the horizon remains straight from top to bottom....at least that is what I remember being told years ago by a projectionist at the UA 150 in Long Island NY. Maybe the lens corrects both focus and geometric distortion? Anyone have any first hand info on this? Here it is on ebay: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200546534595&ssPageName=STRK:MEWAX:IT I wish I had disposable income to buy this beauty. I'd build a curved screen just so I could use it -- actually I loved the D150 curve at that UA theatre. The Curvulon let them projector standard 35mm prints on it without any focus issues at all. 35mm scope looked really sweet on the D150 screen.  |  IP: Logged Bill Gabel Film God Posts: 3873 From: Technicolor / Postworks NY, USA Registered: Jan 2002 posted 08-03-2011 09:27 AM                     Here is some info on the lens. D-150 Curvulon Lens I have one from the UA Egyptian Theatre Hollywood. It's a Very Heavy Lens even without the backup prime lens in the rear.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-03-2011 09:28 AM                     I have one thats a decoration atop my dresser. You are correct in that it corrected geometric distortion. This is simply an attachment lens much like an anamorphic lens and a variety of Kollmorgen 4" diameter back up lenses screw directly on to it. The Kollmorgen back up lens on mine has an added aperature and one would assume that was the attempt to increase focus depth. The lens is way too heavy to mount in anything but a DP-70 and I'm pretty sure all the U.S. D-150 locations were DP-70 equipped. The lens could actually serve as an anchor for a small ski boat!  |  IP: Logged Brian Guckian Jedi Master Film Handler Posts: 594 From: Dublin, Ireland Registered: Apr 2003 posted 08-03-2011 09:44 AM                     Here's a link Frank to an article written by Dr. Richard Vetter himself on the subject, over at in70mm.com: [EDIT - I see Bill Gabel got there first!] The projection field curvature was variable according to the spacing between the two lens doublets employed in the design. Dr. Vetter states that with the appropriate choice of prime lens and the Super Curvulon lens set to the required magnification, the correct net focal length, field curvature and screen image width with precise focus center to edge were obtained. It certainly would be a valuable acquisition. A D-150 Super Curvulon lens is used to great effect at Pictureville, Bradford, UK when they do 70mm presentations on their Cinerama screen.  |  IP: Logged Bill Gabel Film God Posts: 3873 From: Technicolor / Postworks NY, USA Registered: Jan 2002 posted 08-03-2011 09:51 AM                     True most US D-150 locations were equipped with DP-70s. But there was a few locations that were equipped with DP-75s and Century JJ model projectors in the US.  |  IP: Logged Lionel Fouillen Expert Film Handler Posts: 230 From: Belgium Registered: Nov 2002 posted 08-03-2011 10:22 AM                     The ODEON MARBLE ARCH in London had Cinemeccanica V8 projectors when it opened with D-150. Scanned magazine about the installation  |  IP: Logged Bob Bregazzi Film Handler Posts: 17 From: Hampshie, England Registered: Jan 2010 posted 08-03-2011 11:05 AM                     The Odeon Marble Arch was the first cinema i ever worked in. At the time i was there (1968. if i remember correctly the D150 picture size was 75'x 29'. At the time i was there Dr. Doolittle was showing in normal 70mm Todd-AO. Fox stipulated in the contract that no picture size could be as big as the D150, hence normal 70mm was about 68', which in itself looked lovely on that screen and I believe the normal 70mm lens were curvature corrected. There were 3 vic 8's. It used to be a beautiful theatre but was carved up into 5 screens.  |  IP: Logged Lionel Fouillen Expert Film Handler Posts: 230 From: Belgium Registered: Nov 2002 posted 08-03-2011 12:28 PM                     Bob, I saw The Temple of Doom and Lawrence' 1989 restoration in 70mm at Marble Arch. As far as I remember, The Temple was projected on the original curved screen on the standard surface you mentioned. Unfortunately for Lawrence, the screen had been flattened, they say at David Lean's request. Too bad it was split in 5 in the 1990's, although the original stage and front rows remain intact but underexploited by the new 35mm-only installation.  |  IP: Logged Bob Bregazzi Film Handler Posts: 17 From: Hampshie, England Registered: Jan 2010 posted 08-03-2011 02:24 PM                     yes you are right Lionel, it was at DL's request, he was a wee bit perturbed by the amount of distortion on the desert scenes. I saw "close encounters" and "return of the jedi" both in 70mm. although the cinema was not in the "west end" it was always considered one in the early years, but being of the beaten track turned into a bit of a white elephant.  |  IP: Logged Lionel Fouillen Expert Film Handler Posts: 230 From: Belgium Registered: Nov 2002 posted 08-04-2011 05:10 AM                     [YouTube] Odeon Marble Arch Showing the flatter screen in what's left of the Odeon. In the new projection booth they built in front of the former circle, it seems they kept an original Vic projector, albeit with a new Christie lamphouse. But is it a Vic 8 ? I always thought Vic 8 never were built with single-lens holders. Could this be a Vic X ?  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-04-2011 11:04 AM                        I have used a Magnecom 65 pushed fully together for nearly the same effect. If you have a long enough f/l of the prime, it will pass 70mm film. The previous lens in this house was an old Cinemrama 70 lens. The deep curve screen needed the help. The Magnecom lens used this way caused the center of the picture to focus about 25 deet deeper than the sides. At least the Schneider didn't change the color, and was much brighter than the Cinerama. Louis  |  IP: Logged Hillary Charles Jedi Master Film Handler Posts: 748 From: York, PA, USA Registered: Feb 2001 posted 08-04-2011 01:56 PM                     This looks like one of those lenses in action. The same poster also uploaded some other D-150 related pictures.  |  IP: Logged Bill Gabel Film God Posts: 3873 From: Technicolor / Postworks NY, USA Registered: Jan 2002 posted 08-04-2011 02:38 PM                     quote: Hillary Charles The same poster also uploaded some other D-150 related pictures. Yes, I did that yesterday on that site.  |  IP: Logged Hillary Charles Jedi Master Film Handler Posts: 748 From: York, PA, USA Registered: Feb 2001 posted 08-04-2011 02:41 PM                     So you're the mysterious "William"! Small world! Thanks for sharing those great photos.  |  IP: Logged Bruce Hansen Jedi Master Film Handler Posts: 847 From: Stone Mountain, GA, USA Registered: Dec 1999 posted 08-04-2011 05:06 PM                     quote: The lens could actually serve as an anchor for a small ski boat! Mark. I have a small ski boat. would you like me to give that lens a try?  |  IP: Logged

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