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Author Topic: Simplex XL aperture instability Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 03-19-2006 09:04 AM                        We got new lenses for dual Simplex XLs (curved gates) so I decided this was a good time to prefocus all my lens formats and double check the accuracy of the plates. Turns out, the plates don't seem to sit properly when they are inserted. They don't have that positive feel that I get with Century plates or Simplex 35 heads or even Super Simplexs with the old style plates (no bakelite handles). When I insert the plates, they can be moved all around; they go in so far that the handle hits the edge of the housing, clearly putting it way past where it should be (way off centerline). Surely this isn't what it should be, right? Shouldn't the plate sit firmly in only one position and snap into one place? If you wiggle the handle on these plates, they will even sit unevenly, i.e., not square. Also, both the heads had water-cooled gates installed just before we bought them. Did they leave out something? I certaintly can't file if they don't sit true.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 03-19-2006 02:38 PM                     quote: Frank Angel Did they leave out something? Yea, the good design, and then Strong got ahold of it...... ! There should be a spring assy part number G-2126 in the trap that forces the aperature plate back against the cooling block(does it qualify as a cooling block?). So be sure this spring is in there and in good shape. Thats all that holds it in place. Mark  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 03-20-2006 12:56 AM                        Thanks Mark. I'll buy a pair from you -- they obviously aren't in there or they aren't doing what they should. Thing is, the old Super Simplex plates seem to have much less play than the XL plates. I haven't taken the head apart to have a look-see at what's going on. BTW, these projectors are not Strong versions. They are original out of NJ, International Projection Company Simplexes.  |  IP: Logged John Eickhof Jedi Master Film Handler Posts: 588 From: Wendell, ID USA Registered: Jan 2000 posted 03-20-2006 11:35 AM                        It sounds like they never installed the air cooled heat shield plates w/ aperture retaining spring like mark said, or the film traps are older water only type castings and need to be replaced with ones machined for the aperture plate and stop pin...Let me know what you find I have lots of used traps for air cooled curved gates and they install easily with one screw. John  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 03-21-2006 09:48 AM                        Someone once mentioned to me that he didn't think that using the water pump aparratus on Simplexes was worth the trouble. He said they hardly do any significant amount of cooling and with a carbon arc burning only 80amps, the said I really didn't need water cooled. But DAMN it is so cool (no pun inteneded). I only have 40ft wide screen, so I get decent light even on 1.85. BTW, we had the Joe and Shirley Wershbas in for a screening of GOOD NIGHT AND GOOD LUCK (the are portrayed in the film and they were Brooklyn College alumni). Warner Bros, bless their hearts, sent us a high-silver content EK print. Is it my imagination, but does B&W just sizzle off the screen....it was soooo sharp and full of incredible detail. With my spanking new ISCO's, I really thought I was looking at 70mm. DAMN 35mm can look good! Anyway, one of the pumps crapped out just the day before and I got really worried. I wasn't about to be the one to damage a show print; what with black and white and high silver and all, I thought this could really be a disaster -- I was prepaired to go to Grangers and buy a submersible pond pump, which is what is in there anyway. But before panic set in, decided to take a leader that had lots of full black frames and loop it -- ran it for about 10 turns. No damage at all, not even a hint of embossing, so I figured I was safe. So, should I retain all that water cooled business or just install air cooled blocks? I mean, 80amps carbon arc is like 3600w....I am not sure how eqivalent carbon arc light energy translates in terms of wattage to xenon light energy, but my understanding is that you don't need to go to water cooled gates with xenon until up around 4000w - 4500w bulbs. If a B&W print is not burned by this lamphouse, then there is no question I am perfectly safe with color, right? But if I go with air cooled, then I will miss all those ooohs and ahhhs when the professors bring film majors up to see the booth and I show them the big tubs of water and circulating tubes. I guess I will just have to make sure when I stike the arc, I hold the rods close a few seconds longer than usual to make them spit and hiss, then pull them apart and quickly open the lamphouse door so they can see the red-hot tips and the residual flame. That gets them pretty good too.  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 03-21-2006 10:26 AM                        Water cooled gates are very useful to keep the gate temperatures comfortable (no burnt fingers), which can help reduce film abrasion by reducing buildup of hardened gelatin on the rails/bands. But heat damage to the image area of a print is caused mostly by RADIANT energy absorbed by the image. RADIANT energy issues are best addressed by proper alignment and focusing of the lamphouse optics (No hot spots!), and by the use of efficient heat filtration (dichroic reflectors and/or heat filters). Silver image and "silver retention process" films absorb much more infrared energy than regular color prints, so paying attention to possible heat issues is especially important for B&W prints and color prints with silver-enhanced images: Heat Damage Part 1 Heat Damage Part 2  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 03-21-2006 12:43 PM                        Frank: very-old timers still refer to black & white film as "fine grain." Color film, by definition, cannot match single layer film for sharpness (but I sure would not want to return to b&w.) Louis  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 03-21-2006 07:51 PM                     Gee Louis, you don't like B&W? I feel that great B&W is the highest expression of the art form. B&W cinematography is a lost art. Most of the big classics ARE big classics and greatly aided by the magnificent B&W cinematography they contain! You must live a colorful life . P.S. The B&W print film that was commonly used is called Fine Grain Positive..... Mark  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 03-21-2006 11:43 PM                     ..b/w.. is easy to print as well... and a work of art to present. I remember some early B/W prints that were encoded with the digital tracks on difficult the readers were reading the silver based tracks instead of the color ones that were normally used. When one is running a used print of "Goodnight" - it's easy to see that some lamphouses were not focued correctly with the heat blistering on the emulsion to do the silver emulsion soaking up the heat in the dark sections and what size of aperture plate was used.. ..and had to definitely zip that B/W print with FG before showing. - monte  |  IP: Logged Carl Martin Phenomenal Film Handler Posts: 1424 From: Oakland, CA, USA Registered: Feb 2002 posted 03-22-2006 04:43 AM                        the srd track on our gngl print has been scratched off since we got it (played at least 2 theaters prior) and that area keeps shedding like crazy every show. we've had it about a month now, and run almost every show through (dry) media. be glad to be rid of it friday.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 03-22-2006 11:42 AM                        Mark: Color....and B&W......certainly both have their place; just lenses like non-color better. Louis  |  IP: Logged

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