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Author Topic: SIMPLEX X-L: Perfuct Focus? Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-09-2014 12:10 PM                     The rods Louis refers to are the pins or shafts the actual film gate slide onto and is then held tightly in place with two big nuts. These rods determine the straight align of the film against the trap but the original design had the trap determine the alignment. This may be a weakness of the xl after the curved gate was introduced because it relies on those two rods for precision alignment. I have found the lens reducer's or lens holders to be less than perfect as well.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 01-09-2014 07:09 PM                       Oh, those shafts. I've never seen these be a problem. I close the gate and then tighten the knurled gate nuts. Kind of self aligning that way. As to the lens bushings, they are awful but not the real problem with uneven focus, it's more about being somewhat eccentric, but rotating them does not cause any out of focus, just the picture shifting around. The issue I don't care for is the gate stop being all over the place and the curve in the intermittent tang that hold the shoe being off the proper radius.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-09-2014 07:50 PM                     Sam if those shafts are bent,wouldn't your self align upon gate closure in fact be a tic off affecting side to side focus? On a curved gate that is... My lens holders have been around the block and perhaps dropped or ground down with a grinder because they all perform differently. I have many and continue to buy them. I have one xl head with a bunch of issues in the focus assembly such as the threads on the focus knob shaft.  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 01-09-2014 09:07 PM                     I don't recall having many issue with XL's. I even own one, but it's not being used on a large screen and I've never had focus issues with my particular set up. BUT- - back in the 1970's I worked at one venue that had the 35/70mm version of the XL and I was never happy with the image steadiness or edge focus. I've heard that their 35/70 machines were not engeneered very well, and to make matters worse, the theater it was at had a huge screen and a short throw, which only maginifed the imperfections. It was especially bad in the winter time when keeping things in focus for the first reel (on each machine) during the first show required constant attention until the lamphouse (one of those huge Ashcraft rotating carbon models) warmed up everything up. I actually had two marks on the focus knob labeled "hot" & "cold" LOL!  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 01-10-2014 08:28 AM                        In the "before-Strong" era, all 70mm XL's were fully built as 35mm machines and then sent to Howard Straight (sp) to be converted. This, according to Howard. I knew him well during his on again, off again relationship with the "boys from Omaha."  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-16-2014 01:11 PM                     What I was most interested in exploring and this is mostly directed at Louis,Steve,Mark and Tony...when using your alignment tools and finding lens to gate is off. What methods do you employ to get it aligned? Ive heard of the Kinoton tools for instance? Steve Guttag once mentioned the analog soundtrack prevents the image from being centered exactly between the perforations.So the image is forced off center and lamp heat will pull the film unevenly. Has anyone seen the result of this? I think I have but I am not certain.When I get the best corner to corner and center focus,if I study just left or right of center I see softness in one small area. I wonder if this softness is that very issue? This is walking up very close to the screen.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 01-16-2014 05:28 PM                     If you check older SMPTE Journals, the uneven focus due to the optical soundtrack offset has been reasonably well documented. Glenn Berggern has published a bit on this. As to getting things aligned. The Kinoton light projector is really to get the reflector in perfect alignment, not the gate/lens mount relationship. For vertical/horizontal...a laser is your friend but before you can pull out your red-dot machine...you need to make sure pitch and yaw are right. For that, Schneider made a great kit that used a dial indicator and some precision ground lens plugs. you mount the lens plug in the lens mount, put the supplied plat in the gate where the film would run (it is 35mm wide)and then start measuring from corner to corner. Shift/shim parts as needed to get everything equally spaced. Once you have that...take a laser and bore-sight it down the centerline of the aperture...then all of the way back to the center of the reflector...you now have established a true centerline from lens, through the aperture to the middle of the light source...while the laser is in there, put a fixture that will simulate the anode of your lamp stem and get the anode support dead center on the laser so it is at the right height. Then use the Kinoton light projector to adjust the reflector to bounce the light back exactly. While one can do an okay job with just the laser, it will never take into account all of the imperfections in the reflector that the actual light will bounce off...The Kinoton device will. You'll see the interference pattern and can center it very easily. When you're done, you'll be amazed at how much more even your light is and how much better focus will be when you have the light going through the optics and hitting the screen rather than bouncing all over the place and being directed at strange angles everywhere.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-16-2014 08:58 PM                     I hope to get those journals one day. The Kinoton light projector too! Perhaps I should just try harder to get a Kinoton. In the meantime I do have lamp alignment that is super bright to the point of flicker. Round black circle in the middle of the screen with lens out. Capable of four corners dark evenly with scope lens in. Just can't believe how stubborn this newer PR 1014 head is regarding a great sharp picture on both formats. I should have kept my old Simplex head in place because it really did respond to my fine tune adjustments. This PR 1014 just trades one issue for another when I make adjustments Can you feel the despair  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 01-17-2014 08:34 AM                        The issue continues to be that the film plane is not quite 90 degrees with the optical centerline. I would also agree that the center of the picture on the film and the optical centerline may or may not be the same depending on the vintage of the Simplex. The "bent" rods I was referring to are best left alone. It is possible to shim the film trap shoes. i use Pepsi/beer can strips between the shoes and their carrier. Try one side, if worse, move the shim to the other side. If better, but not enough, add another thickness.  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-17-2014 02:19 PM                     Thanks Louis I have been shimming the gate shoes for a couple years since you first mentioned it on this thread. It worked great on the old xl head but this PR 1014 head doesn't play ball. For instance. Lets say I got my lamp alignment great and four corners dark evenly is achievable with a bright even picture when lamp focus is backed off(Super Lumex 2500 watt) I start with test film on scope. Study it and then rotate lens 180 degrees and decide which of the two evils to go with. I shim the gate shoes for maximum even focus. Then I switch to flat and it wants the opposite shimming for better focus. Then I will loosen up the lens holder(reducer) and rotate the scope lens to a different position and start all over. It's never very good. Sometimes it's a decent focus between lenses but flat will be off center to far right or left and no amount of rotation of the lens holders concentric action will fix it so it's back to the drawing board. I do adjust the front right left of the lens assembly to make flat and scope agree horizontally. If fact everything anyone's ever said in this thread has been tried(except using those specialist tools) and worked on the old head. I have 3 sets of scope lenses(Ultrastar HD) and 7 lens holders. My only solution is to adjust for one format at a time before a show. Then undue the shimming adjustments when I need the other format. It works but that's a lot of work and not realistic if I were running lots of film. I guess it's lucky we went digital when I got the PR 1014 head!  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 01-17-2014 02:57 PM                        Use the scope backup lens only to eliminate one of two variables (the anamorphic.) It needs to be razorsharp corner to corner FIRST. Only then will lamp alignment be a factor. Once scope backup is good, then test with flat. Both should agree. The reason you have gone in circles is that you are chasing two (or more) variables at the same time. Lens alignment to the gate is always first. Louis  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-17-2014 04:54 PM                     Ok Louis Ill give that procedure a more thorough try. Do you believe in having any spacer between the prime and anamorphic? Ive gotten vague answers about that or some say yes and some say no. Prime = 110mm throw = 87' screen width =32' Ive tried spacers in the past but in the excitement of running around in circles chasing multiple problems,not sure what the differences were?  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 01-17-2014 06:46 PM                       I agree with Louis about going back and testing with just the scope and flat prime lenses. Note the footage marks on the scopes are important but not all that accurate. I don't think spacer tubes are needed or matter at all at this long focal length.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 01-18-2014 06:35 AM                        Spacers don't matter unless you are at short focal lengths. Special fittings are used then to get the lenses closer. Otherwise you lose your corners. Louis  |  IP: Logged Victor Liorentas Jedi Master Film Handler Posts: 800 From: london ontario canada Registered: May 2009 posted 01-20-2014 01:37 PM                     It's hard on the eyes to look at the 35PA test film through the prime lens only. It's so bright and hard to make out fine detail from the booth. I have to walk right up to the screen. I see some pumping at the top and bottom and travel ghost (tiny bit)at the top and bottom moving towards center. I installed a rebuilt shutter assembly. Could it be bad anyway or can the intermittent be part of the problem.(picture is steady)Also sanded and painted shutter blade flat black. Depending which lens holder (reducer) I use,I get different problems with focus. One gives me good focus except the bottom of the screen. Another gives me top and bottom softness if middle is sharp. This is the same crap I see with the anamorphic on by the way. I have 4 different prime lenses 7 lens reducers and 3 Ultra HD anamorphic's. I only spent 2 hours on this last night,trying just a couple different prime lenses and reducers. Let's just consider for a moment the soft at the bottom system. How would you know if the issue is gate shoe assembly , lens assembly or reducer (assuming lens is fine)? Lets say I shimmed and tinkered for even sharpness on the prime lens. How on Gods green earth am I going to loosen up the lens reducer,get the anamorphic back on,tighten the lens back in the reducer without anything changing? I know I could mark everything first but once it's back together, you only have two positions which the anamorphic can sit in the projector. The odds of everything being exactly the same after the scope is back on seems slim. Some of these lens reducer's have trouble gripping lenses tightly or the projector lens assembly can't grip the reducer OR you can't get the lens reducer into the lens assembly! Are these parts this bad new on new installs? Do I just have bad luck buying used parts? Would I be better off with a turret head? Keep in mind that my issues are small here(except this travel ghost nonsense) ! I am mostly being super critical since I am the last man standing in this city of mine playing with film. I want to do it justice. Also...with everyone so used to complete sharpness at all times with Digital Cinema (one of it's strengths), any focus issue or travel ghost like smearing seems to stand out more than ever. Even a few specks of dust seem more offensive than it used to but that's what filmguard is for!  |  IP: Logged

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