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Author Topic: Achieving a sharp focus on Simplex 1050 projectors Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 06-05-2008 02:22 PM                        In the topic titled "Anamorphic lens question", the link to the tip on focusing anamorphics mention that if you don't have a sharp focus in flat, then you have other issues. I have 3 Simplex 1050 houses and I've never been happy with the focus on any of them in either flat or scope. Even with the focus knob dialed in to the best focus, it's still a bit soft. What can I do to improve the the focus.  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 06-05-2008 03:53 PM                        How old are your lenses? Are they the proper lenses for your set-up?  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 06-05-2008 07:26 PM                     I think we could answer better if you could tell us: Lamp wattage; throw (distance to screen) and size of screen; lamphouse make/model; lens make/model; how bright is your screen image (ideally in foot-lamberts, but barring that, a subjective assessment -- bright, dim, normal -- would help). Curved gate or straight gate? [Maybe that's implied by "Simplex 1050," I've never spent any time with simplexes] Have you run RP40 test film and measured the resolution target? How many lines-per-mm can you resolve? Have you cleaned your lenses? See other threads; definitely cleaning them too often is bad (and opinions differ; probably optimum is somewhere between 1/month and 1/year), but if you haven't cleaned them in years or many months, that's something to look at. Be sure to use the right tools (ideally lens paper and lens fluid). Generally speaking, newer lenses give you better images. More light with a greater f-stop (smaller aperture) will give you better depth-of-focus and thus easier focusing. Curved gates focus better than straight gates, because of the effect of heat on the film in the gate. --jhawk  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 06-05-2008 08:09 PM                        jhawk I'll get that info and post a follow up. EDIT XeTron XCN lamp house with an Osram 3K bulb horizontal mount. Screen is ~37.5' x 16' (scope). It's a curved screen if that matters. Throw is 60' +/- 6" since I don't have a long tape. Flat lens: Schneider Super-Cinelux 2/42.5mm 1.67in Scope lens: Schneider Cinelux Anamorphic 2X MC (I noticed that at least 1 lens doesn't have the MC). To the best of my knowledge, these are the original lenses from when the equipment was first installed 11+ years ago. I assume the lenses were new when installed since all the other equipment was new. Port windows have two sheets of glass separated by about 3". The auditorium side glass has about a 10° angle. I don't have a light meter, but I would describe all the screens as normal to slightly bright. The bulbs have a low of ~500 hours to <2000 and were set for ~82-84amps at ~24V. Hopefully that all makes sense. If there's more info you need, let me know. [ 06-06-2008, 12:31 AM: Message edited by: Justin Hamaker ]  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-06-2008 08:04 AM                     I've never been impressed by using two sheets of glass. You may have the 2 pane Goldberg ports. Simple way to tell is to take the glass out and eliminate it to see if the problem goes away, its possible someone may have damaged a pane over the years and replaced it with something else from the hardware store that would probably be substandard. If thats not the problem then try this. You have decent lenses, if the focus problem is occuring in both formats then be very sure lamp alignment is correct and if good then inspect the gate and tray very carefully. If in one format only then inspect that particuluar lens very carefully and substitute with another if possible. Hope this helps... Mark  |  IP: Logged Larry Myers Master Film Handler Posts: 371 From: Herndon, VA, USA Registered: Jan 2001 posted 06-06-2008 08:24 PM                 I don't like the Schneider Super Cinelux lenses because they can be taken apart more then you should be able to take them apart. Meaning, if they are not put back together with a laser alignment tool, they will never be sharp again. Same goes for the Schneider Anamorphic. I just bet you will find that the lens or lenses were taken apart to get at a piece of dirt. I have seen at least 2 Schneider Super Cinelux lenses like this and both were 45mm.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 06-06-2008 08:49 PM                        Remember short focal length lenses will tolerate no errors at all on alignment (lamp) or mechanical gate alignment. Not only that but the picture is BIG and noticeable. Using an RP-40 and a lens alignment tube, make certain that the center of the image is the center of the lens. Then adjust or shim the gate to show all 4 corners out-of-focus at the same rate. Strong Simplexes are notoriously out of whack. Louis  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-07-2008 07:41 AM                     Okay, There are several possibilities in play here. You say you have Simplex 1050s. These have turrets and may be equipped with straight or curved gates. You also have Schneider lenses and curved screens. You also say you don't like the image on both FLAT and Scope. Lets start with FLAT. If you have a straight gate, you are working with a bit of a disadvantage. First off, with a 3KW lamp, you are going to deform the image a bit as a stright gate does not control the film well enough when it heats up...it will swell towards the light. The other problem with a straight in a typical modern theatre is that the projectionist isn't likely to really clean the straight gate as well as it needs. The runners and guides will often collect emulsion and other film debris and eventually pinch the film causing it to no longer run even, resulting in uneven focus across the image. You really must regularly remove the trap and keep it operating room clean. Presumming curved gates...again ensure they are completly clean (runners and trap bands). Are your focus problems that you have no area of the screen is in focus or just that you can have a portion in focus but not all of it? You need to ensure that the lenses are square to the film path. The 1050 turret is notorious for coming out of calibration since it must be swung away for threading (or lens change) and the nylon stop screw wears or just was not set properly to begin with. Likewise you need to ensure that when you focus, the lens isn't moving vertically either (or that the turret isn't loose in its track allowing the lens plate to sag). Schneider lenses are most finicky about being exactly square to the film, any deviation will come off of uniform focus. For checking and setting this, you MUST have a good target film...I suggest 35PA and not Schneider's...the Schneider film has too much black for this sort of check and will deform from absorbing too much heat. Have a set of binoculars or a spot scope and verify that all portions of the screen are uniformly focused. As to Schneider lenses being too dissasemblable, Larry, an awful lot of people think they are the cat's meow....including those whos current carrers depend on their judgement of image quality. I've never had a problem of a Schneider lens being taken apart. I have had them with loose elements though! I'll put the Schneider ES anamorphic up against the ISCO integrated anamorphic any day and the ISCOs are not detachable whilst the Schneider's are. And unlike you, I judge the image quality based on measured test film in actual projection conditions, not antiquated theory that, by all accounts is either being poorly conveyed to us or just flat out wrong. Steve  |  IP: Logged Richard Hamilton Phenomenal Film Handler Posts: 1341 From: Evansville, Indiana Registered: Jan 2000 posted 06-07-2008 08:13 AM                     Justin, Have you mentioned this problem to your service tech, and if so, what was their response? Have you physically checked the lenses? Take out one of the problem Flat lenses and look through it. Have the projectors possibly been run manually and the lamp left on for periods of time without any film in the projector? Rick  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-07-2008 09:36 AM                     quote: As to Schneider lenses being too dissasemblable, Larry, an awful lot of people think they are the cat's meow....including those whos current carrers depend on their judgement of image quality. I've never had a problem of a Schneider lens being taken apart. I have had them with loose elements though! I more or less agree. Since I have experience as an optical technician myself (Canon USA) I'll say that one does not need a laser tool to align the lens elements in the spherical Schneider lenses... nor the ISCO's for that matter. The barrels are extremely accurately machined and when one re-assembles a Schneider lens there can actually be a short wait for the air to escape between elements and the next one to glide into place. I agree on the loose retaining ring part but this never happens on the present product as they started using a dab of sealent on the rings a number of years back. The only place in the USA that can properly align a scope lens is at Schneider's Century Optics in Burbank. Most scope lenmses even other brands sent to them always come back yeilding higher resolution than they originally had! I'm not in agreement on the ES scope lens although its a vast improvement over any other Schneider anamorphs of the past... I still much prefer the ISCO Blue Star even though its piss poor locking mechansism is an absolutel joke. An easy to make clip on plastic piece will keep it permanently locked once set. Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-07-2008 10:10 AM                     Mark, you actually were in agreement with me on that last point too. Note, I was comparing Schneider's removable ES anamorphic (the compact one) to ISCO's integrated anamorphic (non-removable)...I was not comparing the ES or the WA (full size) to ISCO's Blue Star. The Blue-Star remains my favorite anamorphic, by far. Yes there are/were three sizes of integrated Blue stars, but they are the exception, not the rule as I know of no one that has them. Note, the ES anamorphic also does well on deep curved screens...oddly enough. We are also 100% agreement on the silly one-touch "locking" ring as it doesn't lock. So after spending $$$$ on this fancy lens, I need to tape it to keep the focus from accidentally being altered by the projectionist doing their normal job of changing lenses...just plain silly and anti-climatic. Steve  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 06-07-2008 03:26 PM                        Yea Gads! The dreaded duct (duck) tape. Must be in the South! Louis  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-07-2008 07:56 PM                     Duct tape? How common! I use BLUE Electrical Tape (Scotch 35)! I'd rather it just had a locking ring! Steve  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 06-08-2008 11:37 AM                        Doesnt it melt and turn into gunk all around the outside of the lens?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-08-2008 12:11 PM                     All kidding aside...yes I do use Scotch 35 and no it doesn't turn to gunk...at least not after serveral years...it is one reason not to use crap tape....same goes for splicing tape! I repeat...I just want a locking ring that works...you know...like it USED to. Steve  |  IP: Logged

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