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Author Topic: SIMPLEX X-L: Perfuct Focus? Jarret Chessell Master Film Handler Posts: 288 From: London, Ontario, Canada Registered: Jan 2009 posted 05-11-2009 01:23 AM                     Here are some pictures with a real camera that show what's going on a little bit better. maybe this will help...  |  IP: Logged Vern Dias Film Handler Posts: 28 From: AllenTX USA Registered: Apr 2009 posted 05-11-2009 07:53 AM                        Your new photos confirm that something is definitely wrong and that it actually affects the whole screen. There should not be blue halos surrounding the black as shown in your screen shots. Even in the shot of the center of the test film, these are present. This indicates a problem. I can only reiterate what has been said before. Basic troubleshooting 101: Process of elimination- Split the anamorphic from the prime lens and test the prime alone. Try a different prime lens. Check the image using the flat lens, there should not be any blue fringing even when viewed from 3 o4 feet from the screen. etc. etc. And finally don't be mislead by looking for the extreme issues on the side. Watch the center of the image and examine the image from up close. Any blue fringing indicates a problem. Identify it and correct it. Good luck. Vern  |  IP: Logged Kenneth Wuepper Phenomenal Film Handler Posts: 1026 From: Saginaw, MI, USA Registered: Feb 2002 posted 05-11-2009 08:19 AM                     Jarret, Is the dominant flare always on the right side of all white areas of the test pattern? Have you tested the focus and centering of the lamp house? This effect can be seen when the light is not centered in the aperture. The small areas of white light on the screen are projections of the pin hole sized images on the film. They can produce images of the light source through those holes. If the lamp is not focused and centered properly the result can be what you are seeing. Check out the Christie procedure for focusing the bulb in the reflector. If there is some light coming directly from the cathode (negative electrode) of the bulb, not shadowed by the anode, you can also get this effect. KEN  |  IP: Logged Jarret Chessell Master Film Handler Posts: 288 From: London, Ontario, Canada Registered: Jan 2009 posted 05-12-2009 02:13 PM                     The flare can be controlled. It is centered right now to be the least offensive. Moving the lamp house left and right will change how the blur is on the screen. moving the lamphouse back and forth wont resolve it either. Also, the part of the projector that holds the lens barrel has been played with a bit to help minimize it. It has some rubber grommets under it so we can change the angle of the lens to the rest of the projector (this actually really helped with being able to match up the scope with the flat for screen position). I'm now also certain that all parts of the projector head are present. Hopefully once we get our hands on a laser the problem will stand out more.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-13-2009 06:34 AM                        I don't want to burst your bubble, but the laser presumes that the reflector is concentric. None are. That is why Bill Sanders when he worked for Christie stopped carrying the laser. Good starting point, however. You told me something when you mentioned the rubber grommets; the lens is not aligned with the film. Using a long tube in a dummy lens, a flashlight, and RP-40. you center the lens holder on the centerline of the image, frame exactly, then project the loop on the screen, Cut your plates and only then align the lamphouse. you are then guaranteed that all centers are the same. Regarding centering the scope with the flat: assuming you can shift sideways it is always possible to get these to agree. The scope "moves" twice as fast sideways as the flat. Avoid bending the lens, if you want focus to be acceptable. Louis  |  IP: Logged Jarret Chessell Master Film Handler Posts: 288 From: London, Ontario, Canada Registered: Jan 2009 posted 05-15-2009 07:52 PM                     So... turns out the 70mm Flat ISCO (ultrastar HD dark gold version) shows no sign at all of the issues being experienced with scope. (does anyone know if the f stops are colour coded on the ultrastar HD lenses? - We also have a light gold ultrastar HD lens 65mm). Does anyone know if ISCO makes an ultrastar above 95mm? Do they have something comparable to an ultrastar at that focal length? Because.... we have literally tried four other ISCO and Schneider 105mm prime lenses and they all produce the same blur. We've also tried three different anamorphics. Louis, could you please elaborate more on your tube technique. How would you set this up? What are you using as a tube? A failed attempt of this technique on our end suggests that scope and flat agree to disagree My fellow projectionist Victor has had a lot of trouble getting them to agree using any technique getting flat and scope to agree, up down and side to side don't seem to want to ever work together. To date we've been rotating lenses and barrels to get them to work together as well as they can. Shimming the lens with a business card in the barrel seems to work better than anything else. Just to add some extra info. The projector has a two blade shutter. Both our shutters are sort of a light gray and dark gray, some paint is coming off, not sure what the original colour was. The shutter is in good condition otherwise. Thanks again everyone  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 05-15-2009 08:37 PM                     Are you sure your aperture plates aren't centered differently? If you project with the flat aperture in the scope lens without shimming the scope lens, is it still as far off-center as your current scope image without the shimming? --jhawk  |  IP: Logged Jarret Chessell Master Film Handler Posts: 288 From: London, Ontario, Canada Registered: Jan 2009 posted 05-15-2009 10:21 PM                     Our apertures are filed to the RP-40. If you didn't have an aperture plate in, and you changed the lens from flat to scope you'd see the position change.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-16-2009 06:41 AM                        On an XL it is possible to shift the plate that holds the rod at the top of the lens from left to right. Because of the anamorphic lens, scope shifts twice as fast, hence it is always possible to match left-right centers. The tube is a hollow rod about 16" long with a crosshairs on one end and a pinhole in the bottom of an allen screw on the other. Originally purchased from Xetron back in the early 70's. This mounts in an aluminum dummy lens.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 05-16-2009 12:26 PM                     Hi everyone this is my first post! I work with Jarret at this theater with the unstoppable light blur.A projectionist who worked a while back used to lock the lens assembly to the upper lens holder guide shaft!He would then hide all the allen wrenches forcing all who needed to focus in a hurry to bend or twist the lens when the top stayed still but the bottom focusing knob shaft did move.He was fired for being a lunatic!It was very difficult to get the lens assembly on both machines to free up after that,even with the allen screw loose. Louis you say scope and flat can be made to agree by moving the guide shaft left to right.I have adjusted this guide shaft with my goal to center and unbind focus movement but i will try to get the optical centers to agree as well,i always thought both flat and scope would move the same distance on screen but i see what your saying.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 05-20-2009 09:50 PM                     A quick update! Our problem seems to be the Schneider 105mm prime lens!Even though it looks to be perfectly clean,scratch free glass my older ISCO 105mm is light blur free. Does anyone know if ISCO made a 105mm Ultrastar hd lens?  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-20-2009 10:06 PM                        Shake that lens and see if it rattles. Also unscrew the front from the back of the 105mm lens(metal to metal contact) and see if the elements that face each other are properly mounted. I have had a little problem with older lenses unscrewing due to vibration. We were not expecting the lens, since it was previously swapped with similar results reported. Louis  |  IP: Logged John Wilson Film God Posts: 5438 From: Sydney, Australia. Registered: Dec 1999 posted 05-20-2009 10:15 PM                     quote: Victor Liorentas He was fired for being a lunatic! Good thing by the sounds of it. Victor, these are for you... ...there. Some spaces for you for after your periods.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 05-20-2009 11:03 PM                     When i last used the ISCO 105mm prime the lens assembly was out of square with the gate(pre rubber washers)!I have it aligned much better now so i decided to give it a try and was stunned to see the light flare gone!I bought the Schneider for $150 bucks and love the contrast and sharpness otherwise. I will give it a good shake tomorrow and listen for any sounds.The ISCO is looking better so far but i need to see more film like Gran Torino tomorrow.The ISCO has nothing written on it maybe because previous owners swapped out spacers but it is 1970s era i think. The Schneider is fools gold and only says Schneider 105mm f2?This is why i keep asking if anyone knows if ISCO made Ultrastar in 105mm cause everything i buy on the used market seems older than Schneider or ISCO modern lenses!  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-21-2009 09:20 AM                     ISCO has only made Ultra Stars up to 95mm...ever. ISCO, 100mm and above made Kiptars, Super-Kiptars and Ultras...that is it. Schneider makes a Super-Cinelux 100mm but 105mm and above have only ever ben Cinelux-Ultras, which are similar if not identical designs to the ISCOs. A chief difference in the Schneider's are that they come apart in the middle...which allows one to stop them down, if desired. ISCO has normally had a more consistant lens (pull 10 lenses from each company...the ISCOs will all be pretty similar...the Schneiders will vary a bit). Schneider has also had a lot more trouble with lens elements coming loose for various reasons. Steve  |  IP: Logged

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