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Author Topic: Bad Focus Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 01-20-2004 01:28 AM                        As far as I know you cannot cause any damage to the lens by adjusting the throw setting. If the picture is seriously bad already, it seems to me that in this case there is nothing to lose by experimenting.  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 01-20-2004 09:20 AM                     Fair enough, but 'little allen screws' were mentioned in the original post and tinkering with those could prove disastrous.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 01-20-2004 09:20 AM                     I agree. If done carefully, you have little to lose and a lot to gain. Additionally, I would be inclined to mark (or make note of) the original setting so that, in case you can't fix it, you can at least return the lens to its original setting.  |  IP: Logged Kenneth Wuepper Phenomenal Film Handler Posts: 1026 From: Saginaw, MI, USA Registered: Feb 2002 posted 01-20-2004 04:20 PM                     A word of caution here: What appears to be Allen key adjustments are actually special sockets which require a factory supplied tool. This was done to insure positive setting and locking of the lens as well as preventing unauthorized tampering with the above settings. If you have the tool and the authorization then you could perform the adjustment. Lacking either of these assets, you should seek the permission of the owner/operator of the theatre to have their technician make the adjustment and watch like a Hawk. Perhaps you will both learn a great deal from this exercise and the audience will be the benefactor. KEN Please refer to Schneider ES Anamorphic data on their Web Page.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-20-2004 04:41 PM                     It is a standard metric sized allen wrench that is required they shipped a wera one with the lens  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 01-20-2004 07:34 PM                     The procedure is well described in the "tips" section posting. One screw adjusts the distance focus, the other screw locks the adjustment screw. The only addition to the tips page I want to make is that with "reverse" anamorphics - the internal operation of the lens shrinks the height rather than expanding the width - the procedure is reversed; you focus the vertical lines first and then use the lens adjustment to pull in the horizontals. There's no easy way to tell if your lens is normal or reversed but it will become obvious when the method in the tips page doesn't work right. You need a test film like RP40 with grid lines. Don't try to do the adjustment without it. In a desperate situation one can get close with a clip of edge to edge credits but that's not a good idea.  |  IP: Logged Aldo Baez Master Film Handler Posts: 266 From: USA Registered: Mar 2001 posted 01-21-2004 12:32 AM                    I have this same exact problem as well in several theatres, I have tried the procedure on here and it helped a little but not much. I don't think I am doing it wrong but I don't know. Calling a technician out for something like this isn't feasible even though it looks HORRIBLE. It's either have the bottom part of the screen out of focus or the bottom part ok and the top/middle soft, very annoying.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-21-2004 10:20 AM                     If that is the case you probably have nothing wrong with the lens but have too much of a keystone proble If you can focus the top but not the bottom or the bottom not the top those are the odds unless the lensmount of the projector isn't square to the film plane  |  IP: Logged Aldo Baez Master Film Handler Posts: 266 From: USA Registered: Mar 2001 posted 01-22-2004 08:47 PM                    Would I be able to check if it is square or not? Would I need some advanced tools?  |  IP: Logged William Bunch Film Handler Posts: 87 From: Misawa, Japan Registered: Nov 2001 posted 01-22-2004 10:06 PM                        Wow! This very same topic brings back a vivid memory of a similar problem I had with a Schneider anamorphic. Change over theater with two almost new lenses. The lenses were in use for several months. All of a sudden the scope lens on No.2 just does not look right. After much searching and swapping I find out that one of the elements inside the lens has shifted. The symptom was that it was almost impossible to get focus on anything and there was some double imaging. The lens was not dropped and showed no other sign of tampering. I had to do something and what I remember was loosening some allen screws around a ring facing the film trap. There are two elements in there that must be eliptical. Maybe the first and last. Not sure. I do know that with constant fiddling with that element closest to the trap I was finally able to get back in focus. The name of the Schneider lens was Cinelux. All lenses even from a single maker may not be created equal. Be advised it took me a whole afternoon to get it back in alignment and was really starting to sweat as showtime got near. I used a wide screen credit roll, white on black to focus on. That was several years ago and we had no further trouble after that. I was briefed by someone senior to me at the time that I was definitely in uncharted territory. He said the only real way to align one of these is on a test bench with a laser. Guess I was lucky or just so ignorant the angels forgave me. The show had to go on. We are five thousand miles from USA and only have one screen. You may not want to try this at home. Bill BuncH Misawa, Japan  |  IP: Logged Chris Byrne Expert Film Handler Posts: 102 From: Kirwan, Australia Registered: Jan 2003 posted 01-23-2004 04:47 AM                     quote: to checking for loose elements (a good idea, but not what you might expect from a relatively new lens). Jack, You make a valid point, however all things considered (and basic checks such as cleanliness of the lens, etc) that would be one of my first checks along with ensuring the focus is set right and locking screw is tight on the anamorphic. If an element is in any way loose, the vibration caused by the turret's rotation and sudden jarring when it reaches it limit screw, could work it more so over a period of time. Obviously you should see this get worse over a period of time, and get to it before it is at a stage where a patron notices . How often is the problem something simple? Randy makes a good point to mark equipment so you don't make the problem worse. Sure - know your depth and what you feel comfortable with, but our job often involves dealing with situations that have never happened before. I'm sure a greater percentage of participants on this site have learnt more from 'hands on' than any manual could offer.  |  IP: Logged Will Kutler Phenomenal Film Handler Posts: 1506 From: Tucson, AZ, USA Registered: Feb 2001 posted 01-23-2004 09:17 AM                     I made a post elsewhere some time ago. While at El Con, we had a major problem with mmost of our Schneider lenses. These were all new, and for some reason the elements were all loosening up and it was impossible to maintain focus. Needless to say that there were many customer complaints, and we were busy swapping lenses and prints between screens to prevent dark screens. Wjhat a fiasco that was! Anyhow, you could plainly hear the lenses elements rattle around in the housings. The vast majority of the lenses had to be sent back to Schnieder for repairs.  |  IP: Logged Phil Blake Jedi Master Film Handler Posts: 558 From: esperance western australia Registered: Nov 2003 posted 01-26-2004 08:15 PM                        Hi all, thanks to everyone who offered assistance to me on this problem. I found a loop of schneider test film and followed John Pytlak's tips page on focusing and I now have refocused the scope lens to a point where is is now quite good. I doubt if it will ever be sharp as the other as cinema 3 is a small cinema with the screen very close to seating the front row is only about 15 feet from the screen.(some bad design work) Phil  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 01-26-2004 10:16 PM                        Thanks for the credit, but I believe someone else (Brad Miller?) wrote the "tips" for properly focusing an anamorphic lens using the SMPTE 35-PA test film.  |  IP: Logged Barry Floyd Phenomenal Film Handler Posts: 1079 From: Lebanon, Tennessee, USA Registered: Mar 2000 posted 07-06-2004 12:44 PM                        Bumping this back up to the top because I'm having a problem with my Scope images. Lenses: Schnieder 115mm prime + 1/2 Reverse Anamorphic Adaptor. (Both lenses were purchased NEW in August 2003) Screen: 25' x 60' Throw: 325'-0" (Drive-In) Hanging my head out the back door and looking at the screen, the left and right sides of the Scope image are as crisp as can be, the center of the picture is "fuzzy" and slightly out of focus. It was REALLY noticible on the Spiderman 2 credits, as you could NOT read any of them!!! What's really bad is when customers call from their cell phones to tell you to go focus the "camera". I've pulled the lens and nothing inside looks to be loose or rattles... Any other suggestions?? Since I am the ONLY one with keys to the lens cabinet, and the only person who handles film at our theatre, I can rule out that the lenses may have been dropped. My tech (who showed up as a customer on Saturday night) seemed to think that either the projector was not lined up 90 degrees perpendicular to the screen or that something is wrong with the lens. He ran a loop of test film on Saturday night right before the show, and made what adjustments he could. It's still not right. I didn't have this problem last year.... For what it's worth... the Flat lens and images are razor sharp.  |  IP: Logged

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