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Author Topic: Scope lens replacement glass Justin Frakes Film Handler Posts: 20 From: New Boston, IL, USA Registered: May 2018 posted 06-22-2019 04:18 PM                     Hello again, this year it has been one thing breaking after another. I pulled my scope lens out today and there is a crack in the first glass lens. I'll post some pics of the lens. Thanks for everyone's help. IMG]http://www.film-tech.com/uploads/uploads0503/20190622_155340-477x1008.jpg[/IMG]  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-22-2019 04:24 PM                     What kind of light source are you using. Improperly focused igh intensity light could crack those. As far as replacement glass, those are not paper weights. Look on Epay and get replacement lenses there. Schneider or ISCO would be much better. Mark  |  IP: Logged Justin Frakes Film Handler Posts: 20 From: New Boston, IL, USA Registered: May 2018 posted 06-23-2019 08:21 AM                     4500w xenon lamp, what am I looking for? Are those numbers on the ring the identifiers for that piece of glass? Thanks I haven't ever had to mess with the lens too much.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-23-2019 11:03 AM                     Be sure you have a heat filter in place! The backup is a 100mm lens and The scope lens is a 2X. Look for Schneider or Isco as they are air spaced and not cemented groups. They take heat better, but you still need to have the lamp properly set up and focused accurately. Any hot spots or unevenness in the light when running no film dictate a need for lamp house/lamp alignment. ALSO, NEVER RUN THE WHITE LIGHT MORE THAN 30 SECONDS AT A TIME WITHOUT ALLOWING THE LENS TO COOL!! Run the projector when ever viewing white light! Running the projector cuts the light level roughly in half.  |  IP: Logged Jonathan Wood Expert Film Handler Posts: 206 From: Oxfordshire, United kingdom Registered: Jan 2008 posted 06-23-2019 11:22 AM                     I agree with Mark, I’d replace rather than try to repair . I’ve always thought Iscos had the edge in terms of sharpness and colour . There are usually a good selection on eBay although prices have gone up due to use on DSLRs  |  IP: Logged Marcel Birgelen Film God Posts: 3357 From: Maastricht, Limburg, Netherlands Registered: Feb 2012 posted 06-23-2019 05:11 PM                     As for finding a replacement glass for your lens... I doubt it will ever happen, even if the fractured glass itself is just a simple, spherical one. Maybe if you have the exact focal lengths and type of glass and coatings used in the lens assembly, you might find a spare somewhere... When it comes down to anamorphic lenses, nothing beats ISCO at the moment, although they do come at a hefty price.  |  IP: Logged Helmut Maripuu Film Handler Posts: 25 From: Västerås Västmanland Sweden Registered: Mar 2004 posted 07-01-2019 09:30 AM                     Paper tape between the lens and the lens holder? woov! Overheating?  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 07-31-2019 03:52 PM                        Replace very bad lenses; increase light. Then reduce rectifier to reduce heat.  |  IP: Logged Emiel De Jong Film Handler Posts: 48 From: Geldrop The Netherlands Registered: Mar 2007 posted 08-01-2019 05:51 AM                     It looks like the scope attachment is still intact, only the backup lens is cracked (the Berthiot 100mm) ? You can remove the backup lens from the scope attachment, and replace it with any brand (Isco, Schneider, Sankor even Berthiot etc.) 100mm lens, I guess diameter 62,5 mm. This should be possible for some 10 - 40 dollars on Ebay I guess. Of course it would be a tremendous improvement in picture quality when you get some better lenses; the Berthiot is an antique, the Sankor scope attachment quite bad.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-01-2019 07:17 AM                     Either way, both those lenses are coke bottles, especially that scope lens! I would get some inexpensive Schneiders on Epay to replace them and finally enjoy nice sharp images. Mark  |  IP: Logged

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