Film-Tech Forum ARCHIVE: Resolution of scanned prints?

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Posted by Geoff Jones (Member # 3668) on 12-17-2006, 06:23 PM:

A debate came up recently on my blog.

Me: Film has a higher resolution than digital projection. (He agrees, but neither of us is sure exactly what the "resolution" of film is.)

Him: Most films are digitally scanned for editing, and the resolution of film prints afterwards is limited to the resolution of the scanned version. Therefore, film and digital projection have essentially the same amount of resolution.

Me: Sure, movies are edited in the digital realm, but once the edits are finalized, don't they go back and edit on film itself?

Who's right?

Thanks in advance for any information.

[ 12-24-2006, 04:11 PM: Message edited by: Adam Martin ]

Posted by Joe Redifer (Member # 3) on 12-17-2006, 07:27 PM:

Him. But it really only counts when special effects are involved to my knowledge. Movie image quality pretty much sucks these days, along with movies themselves. That's one of many reason I don't go to theaters any more. Home theater is better in every respect these days.

Posted by Bobby Henderson (Member # 840) on 12-17-2006, 07:32 PM:

Hmm. Sounds like stuff for a FAQ.

Imagery on a 4-perf 35mm original negative on a major film production will have a lot more native resolution than what a typical 2K digital projector can show.

We're talking about a film strip that goes through a very expensive 35mm camera system outfitted with very expensive lens systems. When the cinematography is done very well, a 4-perf 35mm original negative may have as much as 24 million pixels of real image detail.

Not all of that detail is going to get to the movie theater screen due to generational loss that happens in the film print making process. But when the job is done right, you're going to get a good bit more that the 2 million pixels boasted by 1080p HDTV.

The general consensus is 4K digital projection would come a lot closer to equaling the detail of a 35mm print shown under optimum conditions. A 'scope image in 4K would be 4096 X 1716 -a little over 7 million pixels.

A growing number of film productions are having the original camera negatives, or an inter-negative or inter-positive, scanned into computer systems to do all the post processing work. The computer files are referred to as a digital intermediate, or "DI" for short.

Digital intermediates have a number of advantages. It's easier to adjust color, contrast and alter specific areas of the image. The "analog" methods of color timing a film print or using processes like bleach bypass affected the entire image globally. 3D CGI special effects sequences can be composited into a digital intermediate far easier than having to output elements to send to an optical printer.

All that convenience and speed comes at a price: resolution bottleneck.

When a movie is put through a digital intermediate step, it's native resolution is dumped down to the format of that DI file. Right now 2K seems to be the de facto standard. That's due in part to most CGI effects being produced at 2K quality. Lots of movie studios think that standard is good enough.

When a 'scope movie is put through a 2K DI process, the file ends up with 2048 X 858 pixels. That's it. It won't matter if you see the movie in 35mm or 2K digital projection. There's only so much native detail encoded into the DI.

Some movies are processed with 4K quality digital intermediates. But that's pretty rare.

Right now we're seeing a pretty aggressive trend of advancement in computer CPUs, graphics GPUs, memory technology and file storage. Perhaps at some point all that extra brute force computing power will make 4K economical enough for Hollywood to finally embrace it across the board and finally abandon the slightly better than 1080p HD 2K standard.

Posted by Joe Redifer (Member # 3) on 12-17-2006, 08:47 PM:

quote: Teh Bobby
It won't matter if you see the movie in 35mm or 2K digital projection.

Yes it will. On average, the digital image will be much more stable and have better light (35mm projectors are usually drastically underlit). You don't get "high speed printing jitters" which is shakiness that's on the print itself (at least from the digital cinema that I've seen) combined with the shakiness of most under-maintained projectors in todays theaters. How many great, well maintained film theaters are there? Very, very few. Is everyone who participates here at Film-Tech an exception to the overwhelmingly large amount of poor theaters? HELL NO!

Posted by Mike Heenan (Member # 392) on 12-17-2006, 08:58 PM:

What are some movies these days that do not use the DI process?

Posted by Bobby Henderson (Member # 840) on 12-17-2006, 10:14 PM:

I don't know. It seems like every current major movie release I bother to do a search regarding digital intermediate turns out to have used DI. Very few reveal whether 4K DI, featuring quadruple the number of pixels, was used. I'm guessing if they don't mention 4K then they did the good enough 2K thing.

BTW, I should have clarified or better stated that "it won't matter if you see it in 35mm or digital."

There is an assumption that 35mm film based projection will show more image detail than 2K digital projection. But if a 2K digital intermediate is used then the differences in image sharpness for either format is thrown out the window even on the best 35mm projection setups. Basically, if a 2K DI was used, you're better off watching the movie in digital projection.

Perhaps that's one of the points in strategy for distributors to push digital projection to theaters. Give the theaters a 35mm print with image quality that's only so good -and with the jitter and other stuff from high speed printing- and theaters will end up going 2K digital.

I still think the industry wide act of settling on the 2K standard for DI, CGI and projection is a hazardous act that makes theaters vulnerable. I know the bit rates for digital projection is a lot greater than HD-DVD or Blu-Ray. But I don't think there's enough of a difference on absolute pixel count to avoid lots of home viewers drawing the conclusion their home HDTV setup is just as good as that 2K theater.

Posted by Ron Curran (Member # 3631) on 12-17-2006, 11:33 PM:

Most of the films featured in Kodak's Film Notes were scanned at 4K when DI was involved.

I don't have the same problem with film quality. Perhaps it is because the majority of the films we screen are not special effects-laden epics.

Some of the Australian and European films look brilliant on the screen - possibly they don't have the budgets to include a lot of special effects.

However, it is my understanding that 4K DI has become standard for editing.

Posted by Scott Norwood (Member # 30) on 12-18-2006, 07:37 AM:

What is usually missing from this type of discussion is that a) there isn't one, single thing called "film" (8mm != 70mm, Kodak != Fuji, modern cameras/lenses != old cameras/lenses etc.) and b) there is more to image quality than resolution (consider greyscale/color depth, lossy compression, jump and weave, etc.).

DI seems to be popular for big-budget productions, but is very rarely used for smaller, low-budget films. Also, pretty much anything made more than a few years ago would predate the use of DI.

Hey, Joe, why do you hate film so much?

Posted by Joe Redifer (Member # 3) on 12-18-2006, 05:42 PM:

I don't, I hate the shitty job theaters do and the crappy way that 98% of them are maintained. Digital cinema remedies this somewhat.

Posted by Bobby Henderson (Member # 840) on 12-18-2006, 06:33 PM:

quote: Ron Curran
However, it is my understanding that 4K DI has become standard for editing.

That's actually not the case. 2K is still very much the de facto standard. 4K is still rarely used. The Da Vinci Code is one of the few recent films that have used an all 4K process.

Spiderman 2 was the first major release to do use an all 4K digital intermediate.

Posted by Tim Reed (Member # 137) on 12-18-2006, 06:34 PM:

Resolution for editing is, what, 720 x 480? It's television monitors.

Posted by Bobby Henderson (Member # 840) on 12-18-2006, 07:02 PM:

Avid has a number of different work flows for film editing. Video is often used as a proxy to get the cuts trimmed just right. When everyone is absolutely happy with the editing scheme then the cut sequence is actually applied to the film strips.

One nice thing about digital intermediate is the editing cuts are not destructive to the original film elements. You're just editing a glorified high bit rate digital video file.

Posted by Sean Weitzel (Member # 244) on 12-18-2006, 07:07 PM:

I believe "Match Point" did not have a DI.

Posted by Cameron Glendinning (Member # 3516) on 12-19-2006, 02:59 AM:

The only time I heard a resolution of 35mm film was over 10 years ago, it was 3300 lines of resolution. Kodak have spent over $1 000 000 000 dollars improving it since then. In reality its the quality of the lens, a prime is sharper than a zoom. Low asa film stocks have better definition.

Unfortunatly Kodaks improvements have been squanded on set, higher asa stocks alow less light to be used for speed on set, therefore quicker production.

The digital interneg is scanned of the original neg, in the traditional aproach, Image quality was lost in the lab as copies were made, internegs ect. final print neg ect and generation loss occured at each stage

16 mm looks much better today transfered digitally to 35mm, rather than going through the optical blow up stage ect in the olden days.

In Australia, ten canoes was our first 4K interneg, it look pretty good to me on 35mm.

At the end of the day, Image from the computer is then transfered electronically back to film.

Posted by Bobby Henderson (Member # 840) on 12-19-2006, 10:44 AM:

Camera lenses and film stocks do indeed have an enormous effect on image sharpness and color quality.

Most major film productions using Panavision or Arri packages usually have really great lens systems that accompany them. It's a somewhat common occurrence for a director of photography to have some lenses custom made and have others improved in order to get the desired camera shot.

Now film stocks are another matter. Kodak has some really great, vividly colorful stocks. However the trend in style for the past few years has been this sort of muted, green-ish and often grainy kind of thing. You lose some native resolution and a lot of color quality with fast ASA stocks. I suppose a lot of directors feel it is more important to eliminate any camera blur on things in motion instead.

Posted by Charles Greenlee (Member # 3856) on 12-21-2006, 10:36 PM:

This touches on my debate of curiousity. DLP or 35mm? I prefer 35mm myself, mainly due to it's self upgradability. Ok, say Christie comes out with a new 8k projector, you just bought your 4k ones, you're screwed. You have to settle for 2nd best, rather than cutting edge. If digital improves, you require new equipment.

On the other hand, Kodak comes out with a new Uber-Chromalustre film, with a higher color saturation, and higher possible resolution. The 35mm theatre has to do what to show a feature that uses the new film? Nothing. The improvment is in the media itself. 35mm hasn't changed too much. The most recent change requireing a hadware upgrade is the dye track.

I'm sure I'll get flash back for this but, just my opinion.

So, how high can current film stocks go? If I print from a 4k source, can the film faithfully reproduce that quality? How about 8k? Higher? At what point would the source quality overwhelm the capability of the film itself? I'm looking at the potential quality of the fil, even if the DI, or other source, is of lower quality. At what quality would film be outclassed?

Posted by Joe Redifer (Member # 3) on 12-22-2006, 01:25 AM:

quote: Charles Greenlee
You have to settle for 2nd best, rather than cutting edge.

"Cutting edge" sucks ass. "Space-age" is so much better.

Posted by Cameron Glendinning (Member # 3516) on 12-22-2006, 01:53 AM:

I must admit that I agree with Joe, Most cinemas are not doing film done right, and it sucks. Accountants make piss poor business decisions. mmmm we can save a few thousand dollars on wages, that cost them millions in return business. Why are the shareholders happy?

quote: Charles Greenlee
If I print from a 4k source, can the film faithfully reproduce that quality?

I would say yes, if you have a rock steady image with an electronic intermittent, great lenses, oh and filmguard. with a print that hasn't been churned through the lab at super high speeds. The biggest loss of resolution is from projector or image shake, that varies between brands and how they are maintained .

If digital, which at the moment also works at 24 frames a second, was to aim for 48 to 60 frames a second, film would be left for dead .

In production, film is still a much better medium to shoot on than the digital cameras out there now.

Posted by Tim Reed (Member # 137) on 12-22-2006, 05:11 AM:

quote: Bobby Henderson
a lot of directors feel it is more important to eliminate any camera blur on things in motion

They're just into that grungy, MTV, "now" look! [Wink]

Posted by Bobby Henderson (Member # 840) on 12-22-2006, 10:23 AM:

quote: Cameron Glendinning
If digital, which at the moment also works at 24 frames a second, was to aim for 48 to 60 frames a second, film would be left for dead.

First, you need a movie actually shot at 48fps or 60fps. Good luck on that happening any time soon. Hollywood couldn't even transition over to 30fps.

Video cameras don't have anywhere near high enough a level of native resolution, much less fast enough image sensors, to do high frame rates like 48fps or 60fps for an entire movie production (especially when stylistic slow motion shots would have to be captured at double or triple those frame rates). So film-based cameras are still going to be necessary for quite some time to come.

quote:
They're just into that grungy, MTV, "now" look!

It's either that or they're riffing off the desaturated newsreel look of Saving Private Ryan.

Posted by Joe Redifer (Member # 3) on 12-22-2006, 06:21 PM:

Video cameras have fast enough image sensors for 60fps, since, you know, all video cameras do operate at 60fps. I don't like the look of 60fps. Looks like TV news. So unless you want your movies looking like TV news, you'll take the current 24fps and you'll all like it and you'll stop complaining about it.

There was a made-for-TV movie on when I was a kid about some guy in jail facing execution or something. The movie was shot on film except for the news reports which were on video. When it switched to 60 discrete images per second for that news reporter footage it hit me like a ton of bricks in the face. Then it would switch back to the telecined 24fps for everything else and I was like "Ahhhh, that's better!". I've probably told that story before, but it bears repeating.

Posted by Bobby Henderson (Member # 840) on 12-22-2006, 07:07 PM:

Yes, 60 interlaced fields per second in 480i is very common. Even 1080i is common.

What I meant was there aren't any video cameras around that shoot in resolutions equivalent to 35mm film or even the 4K digital standard and able to shoot 60 progressive frames per second at those kinds of resolutions. Current CMOS and CCD sensors are just not powerful enough to replace film cameras. The need for slow motion shots will make it necessary to develop high resolution video cameras capable of shooing at rates up to or beyond 200fps.

Posted by Tim Reed (Member # 137) on 12-22-2006, 07:14 PM:

quote: Joe Redifer
it switched to 60 discrete images per second

Don't ya mean 60 fields? [Wink]

Posted by Joe Redifer (Member # 3) on 12-22-2006, 07:45 PM:

I was hoping someone would point that out! Stuff that is shot at 60i has 60 discrete images per second. Field 1 has an image of a guy moving his arm up. Field 2 will have his arm a little higher. Field 3 the arm will be even higher.... and so on and so on. Even though 2 fields=1 frame, you can have 60 individual "half-resolution" images per second. For example you could have pictures of 60 different movie posters and show them all in 1 second. You wouldn't be able to discern what most of them were while playing the video back, but they'd be there.

Posted by Cameron Glendinning (Member # 3516) on 12-22-2006, 08:02 PM:

Joe I'm not talking about fields per second / odd and even lines being refreshed, I'm talking about progressive scan / frames per second.

Yes this idea has facinated me for a very long time and has produced some very interesting conversations over the years. One was with a cinematographer who had shot both a Showscan and an Imax film about Sydney. He much prefered Showscan, its 60 frames a second and absolute lack of motion blur.
quote "In Showscan, when I shot the harbour bridge from the helecopter, you could count every bolt, all six million of them. In Imax it was a case of what bolts?

The other was with an Imax technician who was the project manager of the 3d SR projector. He told me that he had personally been involved in their atempt to do a 48 frame per second \12 ft per second version of Imax. quote "for the 40 seconds that it ran before the film shreaded and distroyed the projector. The Image looked like you were looking though a six story high window, not a cinema screen."

At the moment each frame of film at 24 per second is repeated twice, all I am is curious to to see is what it would look like if it was 48 individual images per sec, film or digital.

quote:
The movie was shot on film except for the news reports which were on video. When it switched to 60 discrete images per second for that news reporter footage it hit me like a ton of bricks in the face. Then it would switch back to the telecined 24fps for everything else and I was like "Ahhhh, that's better!".

That comment reminds me of a monte python sketch, We are surrounded by film! Brittish programs from the 60s to the 80's use to be studio shot on tape, location footage 16mm. so when they went outside it looked noticably different.

In the early 1990's in Australia a Tv show called "Frontline" a spoof current afairs show went for the same effect. This was produced at the same Tv station that I had worked for in there cinecamera section the years before. It was shot in 3ccd hi 8, on air bits went straight, behind the scenes footage was edited and then kinied (tv monitor filmed) on 16 mm reversal stock and then telecined back to tape. This was suprisingly effective for the purpose, That team latter went on to make the feature films " The Castle "(super 16mm) and "The Dish " (35mm).

Now that there are consumer level genuine hd (not crappy HDV) cameras by Panasonic that capture at 60 frames a second (vari cam)and output 24p, I do think its getting possible, I just dont see a desire.

Posted by Joe Redifer (Member # 3) on 12-22-2006, 08:32 PM:

60fps has motion blur unless your shutter speed is really high or you don't have anything moving very fast. Perhaps your cinematographer friend is retarded? Anyway, film a golf swing in Showscan, pause on a single frame with your 4-head Showscan VCR and you'll see motion blur. If you increase the shutter speed so that there is no motion blur in the swing, it will look very choppy. What do people have against motion blur, anyway? You see it in real life. I've seen Showscan before. I was not impressed at all. It failed for a reason... it sucked ass.

The only time I ever shoot at 60fps is when I want my footage to look crappy and amateur like everyone else's.

Posted by Cameron Glendinning (Member # 3516) on 12-22-2006, 08:57 PM:

quote: Joe Redifer
Perhaps your cinematographer friend is retarded?

I wish he was my friend, just someone who I ran Imax rushes for, I had seen his showscan film, so I can relate to what he was saying. I personally thought the Imax footage looked like shit compared to the showscan footage, from the same angles ect.

quote: Joe Redifer
What do people have against motion blur, anyway? You see it in real life.

Either you see the detail or you dont, In real life when I look at sydneys harbour bridge from a helecopter I see the bolts, on showscan I see bolts, on Imax and 16mm I don't see bolts. So perhaps if 24 frames per second captured motion blur realisticly, like faster film rates do, I would not have an issue with it.

Perhaps your showscan experience was marred by the simple fact that it wasn't shot by a retarded Australian Cinematographer? [Big Grin]

Posted by Bobby Henderson (Member # 840) on 12-22-2006, 09:17 PM:

Even with normal speed 24fps cinematography on 35mm there will be trade-offs for eliminating motion blur.

You can try using a faster (and more expensive) lens with a larger aperture to increase shutter speeds. That will reduce motion blur in the action. But you'll have a more shallow depth of field with some or lots of the image thrown out of focus, thus blurred anyway.

You can use faster speeds of film. But color quality is reduced and grain becomes more obvious. Some of the same effect applies to video cameras when the sensor gain is increased.

quote: Cameron Glendinning
In Showscan, when I shot the harbour bridge from the helecopter, you could count every bolt, all six million of them. In Imax it was a case of what bolts?

That's a really odd statement.

True 5/70mm 60fps Showscan is a pretty challenging format to shoot since the film format is already large (thus requiring significantly larger lenses) and the format is confined to only 1/60 sec. or faster shutter speeds.

A single IMAX frame is a huge area for a camera lens to cover. But the shutter speed can be slowed to nearly 1/3 of Showscan's limit. So it shouldn't be quite so difficult to shoot at a tighter aperture and gain greater depth of field across the frame.

I've seen a lot of true 15/70 IMAX stuff that just blew me away. That format has an amazing level of image resolution capability -far higher than any electronic video playback format.

It sounds to me if that IMAX image of the bridge was noticeably softer and more blurry (so you couldn't see the bolts) than the Showscan version, then the guy shooting in IMAX just didn't know what the hell he was doing.

Posted by Cameron Glendinning (Member # 3516) on 12-22-2006, 09:52 PM:

quote: Bobby Henderson
then the guy shooting in IMAX just didn't know what the hell he was doing.

Not really the case, he was just disapointed that he hadnt shot it as a still shot on a tripod. the slow movement of the helicopter was enough to completely loose the fine detail. this is whats called motion blur! He was trying to recreate the shots at the directors request that he had done in the showscan film, because they looked so good! (I have never forgoten them.)

Andre Fleuren is the retards name, last feature was Evelyn 2002 web page Evelyn 2002
web page kodaks info on Sydney the story of a city IMAX

Posted by Ron Curran (Member # 3631) on 12-22-2006, 10:13 PM:

The problem with processes such as Showscan and Maxivision48 is that - at that frame speed - you can't retain detail without lots of light. Interiors and deep valleys are difficult to capture.

I gave up an experiment shooting Super 8 at 48 fps coz I couldn't afford the lighting gear.

Would digital intermediate technology be capable of creating a "difference" frame between each adjoining frame? This would eliminate the photographic problems while rendering a higher projection rate possible.

Posted by Bobby Henderson (Member # 840) on 12-22-2006, 10:34 PM:

quote: Cameron Glendinning
Not really the case, he was just disapointed that he hadnt shot it as a still shot on a tripod. the slow movement of the helicopter was enough to completely loose the fine detail.

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.

quote: Ron Curran
Would digital intermediate technology be capable of creating a "difference" frame between each adjoining frame? This would eliminate the photographic problems while rendering a higher projection rate possible.

That would be pretty difficult to do using today's technology. It's easy to create new frames in between key frames on 3D animation, motion graphics and Flash animations. Quite a lot more difficult to do the same thing with photographs. I think the end result would have a slightly ethereal "morphing" look to it rather than anything natural.

I'll bet animators doing the traditional hand drawn stuff wish there was some kind of tool like that. You wouldn't need those hordes of in-between-ers to fill in all the space between the key frames.

Posted by Joe Redifer (Member # 3) on 12-22-2006, 10:49 PM:

quote: Robert Henderson
I've seen a lot of true 15/70 IMAX stuff that just blew me away. That format has an amazing level of image resolution capability -far higher than any electronic video playback format.

Even more than Hi8 and Super VHS? Those formats have over 400 lines of resolution, you know. 400 freakin' lines! They charge a premium for those formats down at Fred Schmidt's and Silo because of how freakin' awesome they are!

Posted by Cameron Glendinning (Member # 3516) on 12-22-2006, 11:08 PM:

Ron, its nice to see your cinema operating as normal [thumbsup]

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

Posted by Bobby Henderson (Member # 840) on 12-23-2006, 09:27 AM:

quote:
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 (boring), unfortunately they did not succeed.They did learn what they were missing out on!

Make a 48fps version of IMAX so they could move the camera around, including taking it off a tripod? That doesn't make any sense. The laws of optics and physics would run to the opposite.

The 15/70 format already has huge exposure and depth of field demands at 24fps. Cutting the maximum exposure time down to a mere 1/48 sec is only going to increase lens size/expense and camera size/weight/expense to get shots comparable to normal IMAX format. That's one of the main reasons why IMAX HD (or whatever they were going to call the 48fps version) never went anywhere.

Normal speed IMAX cameras are already huge and heavy. The standard models are too big and heavy to use in any hand held manner, unless the camera operator has super-hero class strength. I can't see anyone pitching a 48fps version of IMAX, just so they can take the camera off the tripod.
[Razz]

I still contend whoever was doing the photography of that bridge in IMAX botched the job. The 15/70 IMAX format has three times the film negative real estate as Showscan and thus three times the potential for image detail. The Showscan format is merely classic 5/70 sped up 250%.

Posted by Cameron Glendinning (Member # 3516) on 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.

Posted by Bobby Henderson (Member # 840) on 12-23-2006, 05:37 PM:

quote: Cameron Glendinning
Bobby, You can believe what you like. Here is yet another persons point of view.

It's not a matter of "believing what I like." It's far from any matter of opinion. I'm merely pointing out some very basic physical laws that govern photography.

The DOF and exposure needs of IMAX and Showscan have them both suffering trade offs at equal levels. I see no logic in why a Showscan image would show much greater detail than an IMAX shot unless the IMAX shot was goofed up some how. That can certainly happen for a number of different reasons.

Further, there's nothing in Charles L. Barbee's comments that refute what I have said. He even points out the same limits of Showscan I mentioned earlier.

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? I thought we were talking about resolution standards of scanned motion picture negatives.

Posted by Joe Redifer (Member # 3) on 12-23-2006, 07:52 PM:

Sounds like someone here sure is a Showscan fanboy!

Posted by Cameron Glendinning (Member # 3516) on 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.

Posted by Charles Greenlee (Member # 3856) on 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.

Posted by Joe Redifer (Member # 3) on 12-24-2006, 06:51 PM:

If you want a flicker-less world with super-smooth motion, look out your window. I don't want movies to look like real life.

Posted by Charles Greenlee (Member # 3856) on 12-26-2006, 10:44 PM:

quote: Joe Redifer
If you want a flicker-less world with super-smooth motion, look out your window. I don't want movies to look like real life.

I try to avoid that, it depresses me.

Posted by Cameron Glendinning (Member # 3516) on 12-28-2006, 11:22 PM:

quote: Charles Greenlee
This touches on my debate of curiousity. DLP or 35mm? I prefer 35mm myself, mainly due to it's self upgradability.

Well we have covered, film/ digital resolution, ways of improving shortcomings, steadiness and frame rates ect. There is still one significant advantage of film not covered so far and that would be the shutter.

Is film less fatiguing than digital DLP? Is it more comfortable to watch a screen that is blank/ black 55% of the time?

Does anyone know how the image is refreshed, does DLP have a shutter or does it refresh over the constant image like say TV? Does this actually make a difference?

Posted by Charles Greenlee (Member # 3856) on 12-29-2006, 09:09 AM:

quote: Cameron Glendinning
Is film less fatiguing than digital DLP? Is it more comfortable to watch a screen that is blank/ black 55% of the time?

Does anyone know how the image is refreshed, does DLP have a shutter or does it refresh over the constant image like say TV? Does this actually make a difference?

Now you're asking too many questions. Government agents will be at your house in a matter of seconds, put your clothes on. Don't bother to run. That's going to the gate at area 51, and asking about the UFO that just flew by. Good one. :-)

Posted by Tim Reed (Member # 137) on 01-04-2007, 11:44 AM:

quote: Cameron Glendinning
does DLP have a shutter

No. If there's picture on the screen, there's light 100% of that time. The DLP mirrors are capable of changing (on/off) states fast enough to trick your eye into seeing shades of colors... so they're much faster than a shutter could ever be.
[Smile]

[ 01-04-2007, 03:13 PM: Message edited by: Tim Reed ]