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Author Topic: Which anamorphic is better? Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 05-21-2005 10:54 PM                        On the "history of anamorphic lenses" topic, I have a question about mine: they are labelled "Norelco Anamorphic Kiptar 2x Isco-Gottingen" and were purchased new in 1970 for a screening room installation (they focus down to 17'). They are black with silver accents on the locking ring and are used with B&L prime lenses. What's the general consensus on these? Do they suck? How do they compare to the B&L anamorphics from the 1950s and 1960s (which far too many theatres are still using daily)? I have never seen this particular type of lens elsewhere and assume that they were not popular for some reason (expensive? poor quality?).  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-22-2005 09:22 AM                     quote: Steve Guttag They can improve the quality of the image but it still isn't a great lens and inferior to ISCO's anamorphics of any era. Agreed! But they can turn an unusable anamorph into a pretty good one. I've run into a few of these lenses still in service today.... yuck! I once had the good fortune to show a comparison of a Schneider and B&L anamorphic(same back up lens)to Dwight Lindsay. The B&L whihc was a very exceptional one was ton better than the Schnelder was... he was blown away to say the least and at first thought the higher resolution lens was his.... of course all those problems are behind them and their anamorphic lenses are dam good today. Mark Scott, The only thing for sure I know about them is that they are not multi-coated. They are just Flouride coated. Mark  |  IP: Logged Thomas Jonsson Expert Film Handler Posts: 216 From: Bromolla, Sweden Registered: Sep 2003 posted 05-23-2005 03:41 PM                       I use a red Isco f=80mm and the BlueStar anamorphic attachment. Because I have some problems with the weight of the lenses in the Victoria 5´s lens turret (amongst other problems with that machine to get a sharp image) I asked Isco if their new red compact anamorphic was any good, compared to the red/blue combi- nation that I have. They told me it was even better. Anyone who has seen it with his own eyes? Thomas  |  IP: Logged Joshua Waaland Jedi Master Film Handler Posts: 800 From: Cleveland, Ohio Registered: Dec 1999 posted 05-23-2005 05:05 PM                     I am glad someone started a topic on this. I need to get new flat and scope lenses for a short throw. I will be at approximately 20 foot throw. Screen size will be four foot high by ten foot wide max. Here are my problems: 1. I don't have an inkling about anything to do with lenses or the terminology. 2. My experience as a projectionist with lenses consisted of manually changing between lenses or flipping a switch on the turret. 3. I have tried using all the lens calculators and can't figure out WTF they are talking about. 4. I am not taking physics until fall of this year so I know absolutely NOTHING to do with optics. 5. What is a prime lens and are all scope lenses the same? I have a turret on one projector and I heard I will need a (magnacom?) lens. I desperately need help finding new lenses and with the influx of lenses on ebay lately it would be nice to take advantage of the lower prices while I have the chance. Please help! Sorry to hijack your thread Alan.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-23-2005 05:38 PM                     I have compared the compact anamorphic of ISCO's to the red/blue ISCO (Ultra Star PLUS with Blue Star)...anyone that would tell yo that the compact version is better is flat out WRONG and does not know the product and I don't care if they do work for ISCO. The compact anamorphic is their same design of decades ago, it isn't as sharp or as good with contrast or as good with colors. I'm amazed that you would have any focus issues with an Ultra Star Plus with a Blue Star...it is a tough combination to beat. See if your lenses are perpendicular to the gate and that the lamphouse alignment is perfect....it all affects focus.  |  IP: Logged Thomas Jonsson Expert Film Handler Posts: 216 From: Bromolla, Sweden Registered: Sep 2003 posted 05-24-2005 12:52 PM                       Steve, The lens combination that I have (the red/blue) was suggested to me by mr Glenn Berggren at the CinemaExpo Amsterdam a couple of years ago. That´s why I was a bit surprised to hear the combi was better. Unless, ofcourse, Isco has made a brand new one. I´ll ask Isco again this year at the Expo. The focus problems I have, is probably not caused by the lenses. It´s very hard to align a machine (Victoria 5) with nothing to really start from. Everything is adjustable, and the curved gate has no fixed parts. To get a sharp picture, I guess I´ll have to replace the machines and not the lenses. By the way, do you know how much more light efficient a 1-blade high speed shutter is compared to a coventional 2-blade? Thomas  |  IP: Logged Larry Myers Master Film Handler Posts: 371 From: Herndon, VA, USA Registered: Jan 2001 posted 05-24-2005 01:59 PM                 Hi The more a designer tries to make a lens for all people for all uses, the higher the cost. The thread was started by Alan who has a very nice small screening room with a scope screen about 3.5 ft high. In that context, I answered the question. An anamorphic designed for peak performance in all screens at all distances would be very expensive indeed. Now what I am saying is, it looks like the designers of compact Super Cinelux had small screening rooms in mind in the design. On the optical bench with the lens set at 15 ft, astigmatism is fully corrected meaning no astigmatism with about 100 l/mm in both directions using an ISCO Cinelux Ultra as the prime. I would venture to guess that with the blue and red anamorphics set at 15 ft, astigmatism would not be fully corrected. I also bet at 50 ft the red and blue anamorphics have fully corrected astigmatism but the compact anamorphic would not fully corrected. His is typical of all lenses. Lenses have a design peak and they also have a level of good performance around that peak. The issue is where that peak is located. The larger anamorphics with lots of tick marks in the 300 250 200 ft range might peak at 100 ft. With the compact anamorphics with four tick marks at 10 ft 15 ft 30 ft and Infinity, 15 ft would be most likely the aim point for the design. So use the compact at 50 or 100 ft and sure not so good. Use that $3000+ Blue Star anamorphic at 15 feet with a peak point design of 100 or 50 ft and watch that lens not be so good and not worth the money. Even a $100 Nikon enlarger lens has a performance sheet saying what the image range is. It is from 2X to 20X magnification with a peak performance around 11X or 11x14 print form a full frame 35mm. Larry  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-24-2005 05:22 PM                     quote: Larry Myers I would venture to guess that with the blue and red anamorphics set at 15 ft, astigmatism would not be fully corrected. Actually I have used them on dailies running with about a 15 foot throw and it was the cinematographer of that film that remarked that a projector anamorphic as good as the camera anamorphic is now a reality. Indeed it does focus fully corrected at 15 feet.... so good its startling . That is part of the reason its a 6 element lens and partly what you are paying for, but all in all it performs miraculously at any distance. So I would consider it a fully corrected lens able to maintain that correction within its design range. Mark @ CLACO  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-24-2005 05:59 PM                     Again a flaw in using the optical bench for projection lenses is that you don't take into account the for and aft motion of the film itself. The optical bench is presumming a flat plane...good for camera lenses...even enlarger lenses...it has been proven...not good for projection lenses. Just to ad into the mix...since sound on film...the film doesn't even pucker symetrically. I do buy into that the Schneider compact anamorphics were designed to do well in short throw screening rooms though. I've had incredible results with 50mm primes and short throws. Then again...with a mere 22-foot throw on a Blue star...absolute pefection was had too (with less pincushion distortion).  |  IP: Logged Larry Myers Master Film Handler Posts: 371 From: Herndon, VA, USA Registered: Jan 2001 posted 05-24-2005 07:04 PM                 Hi Blue stars may very well be fully corrected at close distances. These are very expensive lenses. My point is, why pay for a very expensive lens designed to be all things to all people when your primary interest is a 4 foot high screen in a 10 foot room. If the compact Super Cinelux is fully corrected at 15 ft and so are the Blue or Red lenses at this same distance, what is the difference? Fully corrected is fully corrected. I very much doubt that a lens with a tick marks running from 300 ft to 10 ft in 25 ft segments would be fully corrected at 10 ft. As for the projector running, depth of focus is depth of focus. It's the same for all lenses at any one f stop. The calculation is ((f-stop X f-stop)X wavelength)x2) or ((2x2)x.500)x2 for 4 microns. All f2 lens have 4 microns of depth of focus at it's diffraction limit. Since the film is way softer then the diffraction limit, 1000 lines per millmeter, the film could move maybe 200 times that distance or 800 microns or twice the thickness of a human hair without a problem. Larry  |  IP: Logged

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