my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Poor Focus Right Hand Side of Screen

Author Topic: Poor Focus Right Hand Side of Screen Ian Bailey Master Film Handler Posts: 317 From: Nambucca Heads, Australia Registered: Jun 2003 posted 06-15-2004 08:49 AM                     Hi I have a Simplex with a Kelmar Gate/Trap/Turret.Can't get good focus(in W/S & C/S)on the right hand side of the screen.Could this simply be that both lenses need to be adjusted horizontally and then the projector repositioned.Screen size is 18ft wide with about a 26ft throw.I know from a previous thread that Mark G. mentioned about using Kelmar Jigs with this Turret,is that the only way to go about it? The other problem with this setup is intermittent picture shake-one show rock steady,the next with the "shivers".I've ordered new bands for the gate and trap(the old ones feel like they are not tensioned equally and are showing signs of wear).Should this improve the picture shake and is there anything else to check? Thanks  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 06-15-2004 09:14 AM                    Does the projector sit at an angle or is it straight on to the screen? Is the shake a jump or a weave. Weaving can be caused by a couple of things. A shaky lens turret or loose lateral guide rollers. If the projector is at an angle it is key stoning and the focus may be a problem in those instances. Some small amounts of keystone focus issues can be adjusted out by shimming the lens in to a slight offset position. I have seen this done before.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 06-15-2004 09:50 AM                     You may want to replace the gate bands if one is worn more than the other an uneven focus will result  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 06-15-2004 12:43 PM                     It may be possible that the lens is just loose or mounted improperly. I know it sounds dumb but I've seen in before.  |  IP: Logged Ian Bailey Master Film Handler Posts: 317 From: Nambucca Heads, Australia Registered: Jun 2003 posted 06-17-2004 03:02 AM                     Darryl the projector is square to the screen,the picture shack is most noticeable in the Credits-I watched the same show finish twice the other day and the first one had steady credits and the second you could see the slight picture shake. The focus problem I feel could be the bands,as Gordon mentioned(which I will replace as soon as I get them)but if not it could be both lenses are not set correctly horizontally but I'm not sure whether I need jigs or not to set the turret. Dominic-the lenses and the turret are not loose or moving. Thanks  |  IP: Logged Mike Pennell Expert Film Handler Posts: 150 From: Tucson, AZ, USA Registered: Apr 2003 posted 06-17-2004 04:49 AM                     Ian is the problem happening on both flat and scope?  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 06-18-2004 01:05 AM                     Sounds like the guide posts for the shoe are sprung. Had that happen to me about 7 years ago. I "wanged" them back with a nut driver slipped on to the shaft. One side of the shoe was making heavier contact than the other side. If you detect this sprung guide posts on a good visual inspection, the error you see should be obvious a keen eye. If you think you can "wang" them back, be very careful. If you whomp it too hard, you'll have a handful of peanuts. By the way, Gordon's comment may be well worth looking at. John Westlund also had a problem just like that with his Century. Turns out the entire back casting (called the GIB in the manual I was looking at) was sprung. If you have a guide pin missing on the back piece of the film trap or if there is a hunk of crap wedged between it, you will definately have one side in and one side out of focus.  |  IP: Logged Peter Hall Master Film Handler Posts: 314 From: London, UK Registered: Dec 2000 posted 06-18-2004 02:09 PM                        Try decreasing the lamp current drastically - if still there this will eliminate lamp focus/ heat. Is is worse on black backgrounds ? If so look at lamp and heat problems..  |  IP: Logged

All times are Central (GMT -6:00)

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.