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Author Topic: 3D setup questions Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 07-10-2008 03:35 PM                     I'm trying to set up a 3D show, over/under using a stereovision stereoflex(?) mirror box. The problem is that if I centre the images in the scope aperture plate, ie the divider line in the middle, when I put the box on the image is way high on the screen. The knob adjusts one image up and down to the other image, this works fine: but the fixed image (left if the box is put on "knob up") doesn't hit the screen centre. Framing down works OK but then one image (left I think, the bottom picture) goes half dark because the image is out of the aperture. I can sort of do it with no aperture plate but it starts to vignette too as the light circle starts to dim out way off centre. Plus it throws ghost images on the ceiling this way. I'm not in the theatre now, but hopefully I can get in tomorrow morning. If anyone can offer any tips I would appreciate it. They also have a side by side 3D show, the lens we used last time is a stereovision single piece lens with a split rear element - from the markings it looks to be made for over/under as well but it worked for side by side last year showing house of wax: an anamorphic is attached to unsqueeze the images. I don't expect any problems with this as it did do all right last year.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 07-10-2008 07:58 PM                     Its been awhile since I've worked with one but did many times in the '80s. I don't remember there being any problem with the Stereovision lens you described just going in and setting up (rotate the lens to get lateral alignment, adjust the knob to get vertical alignment). Would it be too difficult to re-aim (tilt) your projector?  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 07-10-2008 08:42 PM                     Well, they're motiograph pedestals and from a quick look there's no handwheel tilt, it looks like you undo the locking bolts and someone holds the back up and tilts while someone is ready to lock it again... somewhat inconvenient especially when they have scheduled over/under and side by side 3D films both on the same day. There's some time to do setup but having to do a tilt as well would be rather inconvenient... if necessary then OK but I thought maybe I'm missing something. I'm also worried that tilting it will put one image on the projection booth wall... the ports are not overly large.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-10-2008 10:45 PM                     Call Bob Destolphi(Sp.?) at Ultra Flat. He worked for Stereo- Vision for many years and can tell you exactly how to set up the lens. Good luck getting off the phone with him in under three hours though . Mark  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 07-11-2008 03:11 AM                    We had this problem back in the 80's We had to pretty much live with it and put an extender masking at the bottom of the screen. I guess they felt it looked better to do it that way and not try and change the tilt of the machine.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 07-11-2008 08:56 AM                     Mark, I talked to Bob yesterday just before posting. I have to get back to the projectors to try what he suggested later today. The suggestion is to rotate the box to get the image centred and use the knob to align them. This may be right... my fiddling with the boxes didn't lead me to that though. Turning the box shifted the images horizontally relative to each other, turning the knob moved one image vertically. My problem is that the fixed image, not adjustable with the knob, isn't vertically centred on the screen. Everyone I've talked to says they didn't have to tilt the projectors... anyway, I'll have to see what I can see later today. Bob is going to try and get Chris COndon's number for me, hopefully the guy who invented the system can help!  |  IP: Logged Jeff Joseph Expert Film Handler Posts: 131 From: Palmdale, CA, USA Registered: Jun 2000 posted 07-11-2008 02:21 PM                        Dave: Call me (I just PM'd the number); I think I have Condon's phone number. Jeff  |  IP: Logged Robert Throop Master Film Handler Posts: 412 From: Vernon, NY USA Registered: Jun 99 posted 07-11-2008 02:30 PM                     quote: -------------------------------------------------------------------------------- Well, they're motiograph pedestals and from a quick look there's no handwheel tilt, Some of the Motiograph pedestals have a handwheel adjustment inside the access door on the base. Bob  |  IP: Logged Paul H. Rayton Expert Film Handler Posts: 210 From: Los Angeles, CA , USA Registered: Aug 2003 posted 07-11-2008 02:37 PM                    Just a bit of a reminiscence here ... we used these with Jeff's (who posted a few minutes ago) 3-D Expos at the Egyptian, most recently in October of 2006. We had a bit of a problem getting them set up, too -- and it was because one of the mirrors inside had come loose from the backplate, and would not stay in the correct position! It appeared they were attached into the box merely by double-sided sticky tape... I don't want to suggest shaking it, to see if anything is loose inside, but you may want to look carefully inside to see if anything looks amiss as a result of some impact during shipping.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-11-2008 08:10 PM                     The way I set them up Remove the adapter and center the left/right eye septum line to the exact center of the of the projected image (all the projected area that is on the floor and ceiling (isually set card up in front of the machine to set it on If it is a StereoFlex cover the top window and install it and tip the machine up and down to centre the projected image in the masking then unmask the top and turn the knob to bring the second image down to over lap the target Then rotate the lens to do the left right alignment  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 07-12-2008 12:09 AM                       quote: Mark Gulbrandsen Call Bob Destolphi There's two? I know a Bob DeStolfe who is a motion picture still photographer and dailies projectionist...  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-12-2008 10:27 AM                     Tim, There are at least three. Also look up Bob Destolphy . Mark  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 07-12-2008 04:13 PM                     That's basically what's been done now, Gord. I haven't done a setup before and from everyone's memories the projector didn't need to be tilted... poor memories it seems? The problem is that this is a 3D festival, with over/under, side-by-side, and anaglyph movies all mixed up. Luckily I don't have to actually run them and manage the changes of tilt and lenses... The Motiograph pedestals do in fact have handwheels, under one of their many access doors, so tilting is at least a one person job (whew!). Even with the framing centred and the scope aperture plate (pretty close to full width and no cutoff visible on either image) the thing throws ghost images.. you get the left eye on the ceiling and the right eye on the floor, I think. With some more time and experimentation I think some sort of cardboard mask with two holes, placed close enough to the stereoplex box that the 3D images haven't converged together, would block these ghosts. Thanks for all the suggestions. I may try and talk to Mr. Condon on Monday and see what he recalls. Does anyone know if there's still anywhere that can replace the polarizers, or if this is something that I could do? And does anyone have a pair of Sterovision stereoplex units for sale? The Paramount ones I've seen on ebay are too bloody huge: the theatre is asking about buying a pair, and our only rental set is still occasionally used by a few silver screen houses so we don't really want to sell them.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-12-2008 06:52 PM                     I used to buy plastic sheets of polarized material from edmund scientific I have used the paramount boxes at the fox many times Also I only make it a habit of renting lens if they hire me to be there and re algin them per film Also one does need the target loops for each film as there are many different spacing  |  IP: Logged Bill Enos Film God Posts: 2081 From: Richmond, Virginia, USA Registered: Apr 2000 posted 07-13-2008 10:35 PM                     We've got the Paramount boxes and had to enlarge the ports to accommodate them. They work very well and are still available from Surplus Shed. The Stereovision stuff is supposedly not for sale. We bought the Paramount boxes after having problems with StereoVision boxes having loose/misaligned/damaged mirrors and their not having replacement equipment available. We built frames to hold the Para. boxes to the wall on the correct angle and close enough that the lenses slip into the boxes just a little. [ 07-14-2008, 03:50 PM: Message edited by: Bill Enos ]  |  IP: Logged

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