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This topic comprises 3 pages: 1 2 3
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Topic: Resolution of scanned prints? > OT: Frame rate discussion
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Cameron Glendinning
Jedi Master Film Handler
Posts: 845
From: West Ryde, Sydney, NSW Australia
Registered: Dec 2005
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posted 12-22-2006 11:08 PM
Ron, its nice to see your cinema operating as normal ![[thumbsup]](graemlins/thumbsup.gif)
As to your question of creating a frame, I would think so, If a 2d film can be computer enhanced to create a 3d version, It couldnt be ruled out.
I also suspect that 800 asa stocks that are out their now would make shooting at higher frame rates not as difficult as before.
As for your super 8 attempt, bravo for thinking about it! If you want we could try it some time, I have lights and hi speed stocks (infact all 35mm stocks are now avalible) for super 8 are avalable through pro 8 , the 800 is only avalible as neg 100asa for colour reversal web page
So perhaps an outdoor shoot?
I also have a pipe dolly, micro jib, home made stedicam. tripods. several super 8 cameras including one with a schnider lens, a 16mm , Betacam sp, 3 chip mini Dv and sound gear ect, so if you feel like playing with pictures on the other side of the projector, let me know.
quote: Bobby Henderson
I've seen plenty of shots in IMAX made from airplanes and helicopters that were tack sharp. The mounting rig they were using must not have been very good. Normally a camera mounted on a helicopter needs to be contained within a computer/gyroscope controlled setup like a Wescam rig.
And I worked full time with the largest screen in the world, yes an Imax theatre and yes I have seen many Imax movies, and all I can say is that the harbour bridge footage looked sharp, it just didnt have any bolts!!!! your faith in Imax is not shared by Imax technicians. They tried to develop a 48 frame version to solve this problem, so that the camera could be moved and not be locked off on a tripod (borring), unfortunatly they did not succeed.They did learn what they were missing out on! 12 feet of 70mm per second is not going to happen. Both Imax 2d and showscan use 6 ft of 70mm per second aprox)
quote: Bobby Henderson
Normally a camera mounted on a helicopter needs to be contained within a computer/gyroscope controlled setup like a Wescam rig.
Acording to kodak, link in last post, they used spacecam
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Cameron Glendinning
Jedi Master Film Handler
Posts: 845
From: West Ryde, Sydney, NSW Australia
Registered: Dec 2005
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posted 12-23-2006 04:52 PM
Bobby, You can believe what you like. Here is yet another persons point of view. Charles L. Barbee web page
My knowledge of and interest in SHOWSCAN actually began in the early to mid '70's when was spending a good deal of time with Doug Trumbull. I had made a documentary on Doug's feature film, "Silent Running", and we had become friends. At the time, Doug had a company called Future General, which was a subsidiary of Paramount Pictures and a major force modern special effects techniques. While Doug and his then protege, John Dykstra were doing some innovative work with multi-pass, in-camera compositing techniques (early Motion Control), Doug was also experimenting with the idea which ultimately became SHOWSCAN.
Doug, John and I had a common interest in scuba diving and I spent some time with them testing a VISTAVISION underwater housing off Catalina Island. On one of those trips Doug told me of his ideas for SHOWSCAN and showed me his early prototype 35mm system. The basic idea, like many good ideas, was deceptively simple. If you increase the "system speed" of a recording process, you increase the "fidelity" or "definition" of that process. That is the heart of SHOWSCAN. Doug ultimately took it a step further by doing it in the 65/70mm format, but it will work in 8mm, 16mm or 35mm; it works in audio recording and even in video; although it is a little more complicated to make video run faster. However, the basic idea is that moving the tape or film faster will increase the bandwidth of the process and thereby allow you to increase the definition or fidelity proportionately. By speeding up the process you are just sampling and delivering more information in the same amount of time. In addition, the beauty of doing it on film is that you don't have to invent new hardware. The standards are all the same as normal motion pictures of the same format. You just have to make existing hardware go faster.
There are, of course, practical limits to how fast you can go, so Doug did many tests in 35mm. They shot a control scene at the normal 24 frames per second and then a series of identical scenes at ever increasing frame rates. They then brought in test audiences and showed these scenes while measuring audience response in several objective parameters, i.e., Galvanic skin response, heart rate, brain waves, etc. What they found was that audiences responded more actively to scenes as the frame rate increased. However, this increase in response seemed to reach a plateau at about 72 frames per second. So Doug decided to standardize at 60 fps because of its compatibility with the 60-cycle AC electrical standard and because of the 30 frame, 60 field NTSC television standard.
Doug could never get his FUTURE GENERAL'S parent company, Paramount, to back this new idea in any significant way. Paramount ultimately passed on the idea completely and Doug was able to form a new company, which ultimately became Showscan Film Corporation. By 1984, they had produced two spectacular demonstration films, NEW MAGIC and BIG BALL.
As with any technology, SHOWSCAN has advantages and disadvantages. On the screen, SHOWSCAN is all advantages. However, putting it "in the can" presents a few challenges to the Cinematographer. On the positive side, the higher frame rate gives a perception of sharper, more realistic images, because they are in fact sharper due to the faster shutter speed of 1/125 sec. This is a by-product of running a 180-degree shutter at 60 frames per second. Images also appear less grainy. Since the viewer is seeing 2.5 times as many frames per second. That, combined with image retention in human vision prevents the viewer from loosing the image of one frame before receiving another 1.5 frames, each with a different grain pattern. The result is a masking of grain, so that it seems to have gone away. Because Showscan is a flat (non-anamorphic) wide screen system, it uses spherical lenses, which present fewer problems than anamorphics. Finally, because of the increased frame rate and shorter exposure time, lateral (cross screen) motion or panning rates are greatly increased in SHOWSCAN. In fact, a look at the fourth edition of the AMERICAN CINEMATOGRAPHER MANUAL 35mm panning speed recommendations gives a clue to the SHOWSCAN advantage in this area. The text that accompanies the panning speed charts describes the physiological reasons for the "skipping" or "strobing" which results from panning too fast or allowing a too rapid motion across the screen. In addition, the last paragraph of the text mentions how, "early wide screen productions shot in 65/70mm, were shot at 30 frames per second, to smooth panning shots and cross-screen action". It goes on to say that this adverse skipping effect is related to screen brightness, lens focal length, frame rate and shutter opening. What it doesn't mention is that the projected image size, relative to the viewer, is also very important. This was another reason why the 65/70mm format films had more of a "strobing" problem, because they were projected bigger, wider! The 35mm panning speed recommendations were based on a standard screen size. When they exceeded that with larger format, wide screen processes, a higher frame rate solved the problem. Therefore, it is easy to see that at 60 frames per second, SHOWSCAN can handle lateral motion very well.
On the downside of the equation, the increased frame-rate takes light away from the negative. One and one quarter stops to be exact. Also in 65mm there is the approximate doubling of the focal length of the lenses, with the attendant shorter depth of field, for any given shot. This, coupled with the exposure loss can be troublesome, since you end up working at longer focal lengths with larger apertures than you might in 35mm. However, with the new, fast, fine-grained films you do get a little bit back. Finally, there is the rate at which SHOWSCAN uses film. In 65mm there are 12.8 frames per foot. At SHOWSCAN speeds, you're using 4.68 feet per second or 281 feet per minute.
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Cameron Glendinning
Jedi Master Film Handler
Posts: 845
From: West Ryde, Sydney, NSW Australia
Registered: Dec 2005
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posted 12-24-2006 05:51 AM
My comments are about the merits of speeding up the frame rate of film or digital, 72 frames per second provides the scientifically proved ideal, or most realistic image possible. super 8,16mm 35mm and 70mm can all be improved. Digitally Im sure that 72p would be awsome. Perhaps this is the direction Imax should look at with there digital future ?
In an era where most of us agree that 2k technology is not superior to 35mm film. No one is talking about or suggesting better options than 35mm? seriously, I wish 70mm would come back. Cinema is now going to be competing with high definition and cheaper big screens at home, what could be the drawcard (new cinemascope/ color/ mulitrack sound, or other edge over home technoligies), that could be used to fill this role, 3D with cardbord glasses?
Joe is right when he talks about the advantages of 24p and I'm sure that the projectors could be developed to do all 24p, 3D and 48p or 60p and possibly more giving filmakers more choice and possibilities than ever before. I also think that 35mm could be done better and have a higher definition this way. There just has to be a desire.
Am I a Showscan fan, no, just was facinated by ways that could improve the cinema experience, I went to one ridefilm (computer animated) and I thought so what. What did impress me was a special purpose Showscan venue specially built for an expo in 1988.
Having recently seen Cinerama for the first time (which is awsome) I hope Hollywood and cinemas do come up with another fightback campain as they did in the 50's.
quote: Bobby Henderson
I'd still like to know just how IMAX at 48fps would somehow allow a camera operator to shoot the format hand held. Better yet, how did this turn into a Showscan versus IMAX thread?
As for hand held Imax, I never said that, take the camera of the tripod yes and now you can put it on a dolly, or a camera crane or in a helecopter, Imax simply works at its best when the camera is locked off static on a tripod. If you want to see the bolts on the harbour bridge in Imax, thats the way. Though it also looks pretty extrordanary floating weightless in space;) .
As why this has become an imax verses showscan thing , to me its a frame rate thing, one way of increasing the resolution of scanned prints to a level that is better than what an audience has ever seen before, could be as simple as to increase the frame rate of both production and exibition, film or 2k digital.
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Charles Greenlee
Jedi Master Film Handler
Posts: 801
From: Savannah, Ga, U.S.
Registered: Jun 2006
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posted 12-24-2006 02:49 PM
I see icreasing framerate soly as a way to smooth out motion, and reduce flicker. Persistance of vision is far shorter than 1/24th of a sec, at least in my book. Or should I say, with a double shutter, 48 pulses/second, I still percieve flicker. I'd probably notice it on CRT's, but the phosphors have a persitance effect themselves, and glow for a fraction after. At a higer framerate, due to reduced exposure times, or the need for higer film speed and thus larger particles, I can only see you losing quality, for now. Future film stocks maybe different.
Now if you have a film that has the same resolution at 48fps as the current does at 24fps, then as long as your equipment is stable, you may perceive higer resolution.
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