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Author
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Topic: SMPTE hosts John Pytlak
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Frank Angel
Film God
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Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999
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posted 03-22-2002 04:48 AM
This is to applaud John Pytlack for a great demonstration Wednesday night at the SMPTE New York section meeting. He gave a two part presentation that seemed to captivate the audience. First came the more technical of the two and the more fascinating -- it was titled "Scope 1.5 --Squeezing Even Higher Quality from 35mm Prints." It was a working demonstration of an alternative method of producing wide screen images that we have spoken about here on Film-Tech. The demo ran a segment of film producing the ubiquitous 1.85 wide screen image in the usual crop-&-enlarge method which we all know too well. It is inefficient, it compromises image resolution and it sucks up light. It was never a "designed" system, but from the outset, it was merely an exhibitor's attempt to put more of his new CinemaScope screen to use. He figured he already paid for it, and the world was in love with super wide CinemaScope, so crop that 1.37 frame and torture out a wide screen picture and let image quality be damned! Then along came Glenn Berrgren with the better mouse trap -- a system DESIGNED to produce a wide image, but utilizing the entire film geography, not reducing the light transmission and not increasing grain. It's done, of course, with the addition of 1.5x compression in the camera with a corresponding 1.5x anamorphic stretch in the projector. Basically it is "mild" CinemaScope that produces the 1.85:1 ar (or if you want to be nit-picky, 1.78:1 ar). The idea is not new. When Glenn presented it some 20 years ago, he worked at Isco and the process was called IscoVision or was it IscoScope? (help me John). The demo proved the advantages of using all the available image area of the film without any cropping. Especially evident was the much better light output and the increased color saturation. Resolution was improved, but not as dramatically as it might have been. I speculate the reason for this was because the projectors (and I was only able to get a quick glance at them) looked like they might have been those Kinetons. They had what I considered unacceptable weave and jitter. This certainly would impact apparent resolution because any picture unsteadiness translates into less resolution as far as the eye is concerned. Before the 1.5x anamorphic demo, a loop of the SMPTE 35mm Projection Alignment Test Film (SMPTE Cat. # RP40) was run, only to expose the projector's excessive jitter and weave on the relatively small screen. On a screen that small, I would have expected to see a rock steady image from a well maintained intermittent. I don't know if this fairly severe unsteadiness was because of that stepping intermittent Kinetone uses, (although they claim it is as steady or steadier than a Geneva Star), or if it was just not running properly, but it was quite a visible shake, rattle and roll. There is no doubt this elegant 1.5x anamorphic system is miles ahead of what we use now. It was good to see what I intuitively knew would work, being demonstrated practically in a real cinema setting. Question is, will the industry move to it? John and I both agree that the biggest obstacle and perhaps the one thing that could be the death-knell to implementing it, would be the need for double inventory prints during the transition period. Double inventory has always been a killer in this industry, as John knows all to well -- Kodak & Optical Radiation's joint foray into Digital Sound succumbed to the double inventory albatross -- a digital print with no analog track....what could they have been thinking?! It would be a shame if such a beneficial system as the 1.5x anamorphic wide screen were discarded and the present crop & enlarge system remained in place. If we can move exhibs to accept cyan tracks which have relatively little impact on audiences in terms of what they hear in the theatre sound, surely exhibs could be motivated to buy the 1.5x anamorphics, since it would be a palpable improvement that their audiences could see and appreciate (unlike DLP). Plus, 1.5x anamorphic would cost $2000 instead of $130,000. Gee, I know which on *I* would go with! Again, congrats John on a great evening. Frank Oh, and PS -- John is just as brilliant spitting out those SMPTE reference materials and spec standards in the lecture as he is here on the forum, which, by-the-way he plugged three times at the end of the lecture. Wayta go John!
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Steve Guttag
We forgot the crackers Gromit!!!
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Posts: 12814
From: Annapolis, MD
Registered: Dec 1999
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posted 03-22-2002 08:07 AM
I agree with Steve K on this one...just use the Scope lens for everything and blow up the 1.85 stuff to the scope aperture.As to the picture unsteadiness...it wasn't in the projector if they were Kinoton "E" series projectors. They are indeed steadier than conventional intermittents. More than likely, the image movement was right in the SMPTE RP-40 (aka 35-PA) test film if it was the B&W version. I am now getting nearly 100% reject rates on the 35-PA test film. One of the problems with 35-PA as it is produced now, is that the cameras are "pin-registered" and use the perforations as a reference whilst projectors use the edge of the film as a reference. Therefore, any slitting errors or perforation errors in the manufacturer of the film itself will show up as image movement that is not the fault of the projector. Furthermore, 35-PA (B&W) uses BH-1866 perforations (with the short, negative pitch) whereas all projector sprockets are designed to handle KS-1870 perforations (long or standard pitch). I have conducted this test quite a bit now using not only Kinoton but Century and Simplex projectors. Take some B&W 35-PA since they went to polyester base, 35-IQ (magenta, if it is on KS-1870 perfs) and the Schneider test film...only the 35-PA runs unsteady. If the projector was at fault, then the other test films would also exhibit the image movement (most notably is the weave...sometimes as much as 1/2 a block). Steve ------------------ "Old projectionists never die, they just changeover!"
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Frank Angel
Film God
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Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999
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posted 03-23-2002 11:46 PM
Robert,I would like to say, first, that I only glanced at the booth literally for a moment -- I couldn't say for sure if they were Kinotons -- they easily may not have been. And yes, it was the B&W version of the RP40. And I was sitting dead center, second, maybe third row and I must disagree, Bob, the very first thing that came to mind the minute the test film hit the screen (after they rethreaded it right side up), was "geez, how embarrassing is that unsteadiness?!" YOu may be right, there was more weave than vertical jitter, but still, to me, it looked quite excessive for a moderate sized screen. Right after the show I went across the street to visit a friend who works in the LTV Labs -- they cut laser subtitles in foreign films prints. He asked me how the demo went and I mentioned what I saw as unusual picture unsteadiness. He got all excited and said they use the same Tribeca screening room as well as others to quality check their subtitled prints and invariably, the producers would complain that the subtitles were not steady when they were screening in that room. He said when the got the first complaints, they spent weeks testing their equipment trying to track down the problem, but finally came up with the only conclusion that it was the projection equipment and not their laser writer that was giving the illusion that the laser was writing unsteady text. They've since asked that the Tribeca projectionist pull the aperture plate when test screen their work so they can see the sprocket holes along with the subtiles -- resolving any question as to the steadiness of the laser writer. But, I do agree that everything is relative to what you are used to. Two fellows behind me were talking about video imaging and one said how he has worked in the video domain most of his career and there the images are REALLY rock steady (as long as you don't count all that electronic simmering on hard lines, thought I), he said he is so used to the steadiness of 30fps video that it hurts his eyes to watch the unsteadiness of 24fps...HURTS HIS EYES TO WATCH FILM, says he. I did resist the temptation to turn around and ask his opinion about the tendency of tech people to exaggerate wildly when trying to make a point. Robert, now you see the value of you and I taking the time to get our pictures up here on the forum so when we happen into these meeting together, we will be able to recognize each other. Steve. how do you like the Schneider test film? I saw their ad for it and wondered why they thought there was a need for another test film (hopefully, unlike SMPTE, they will give it only one name, re: RP40 & 35PA). I think I remember someone here saying they thought the Schneider film wasn't worth much. I'd be interested in your take on it compaired to the RP40. Also, maybe John P. can answer this -- has anything happened with the contrast test film that was in the works a few years back (SMPTE section meeting in Atlantic City)? I could certainly benefit from it as one of my theatres has walls and ceiling that are painted white -- semi-gloss white. They are not convinced that this unholy design scheme is ruining screen contrast. I would love to put up that Contrast Test film and ask them to read the last number that they can see to me, and it be something like 2 or 3 out of the possible 10.
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Steve Guttag
We forgot the crackers Gromit!!!
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Posts: 12814
From: Annapolis, MD
Registered: Dec 1999
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posted 03-24-2002 01:27 AM
Paul, if you are going to put on the anal mode, please use the proper module! RP-40 describes two test films, 35-PA (B&W) and 35-IQ (Magenta). Like so many things in this industry where competing outfits make seemingly similar products (or products to do essentially the same thing), aside from the usage, you get different ideas on the approach to the situation. The RP-40 document and the test pattern is an evolving one. Originally we had the 35APAL target, then there was the old "RP-40" target that most are familiar with and now the current target. If the SMPTE can revise the target to make changes as deemed important, why can't others make their own targets? The Schneider test film definately has it's uses though I don't think it is as valuable as the RP-40 target for most situations. The Schneider film (I believe the catalog listing of it is CLT-<length> ) is a very black film and will soak up a bunch of heat so it will show up any problems your projection system has if it gets too hot. There is a good grid pattern to show up geometric distortions (SMPTE had the 35-FA test film that was better at this though). If you system is good, the Schneider film will make it look "stunning" with it's sharp black/white contrast. There are many circles/ovals for Cinemascope alignment and the measurement lines (dimensional) are in the more familiar places for leveling and centering (not to mention measuring the projection aperture). It is a test film I now carry on all my alignments so let that speak as to _my_ confidence in it. I often use different test films to look at different areas of measurement and to ensure that there is an agreeance between the test material. Even for 16mm I use 16-RT (kinda like the Schneider test film) and 16-PA (Kinda like the old 35-PA test film). If one test film says one thing and another says another (using the same projector) then something is wrong with the system and that might possibly be the test material. This problem with test films is not limited to the picture side either, if you think all of your sound test films are good, you would be sadly mistaken. We have taken to measuring the test film against previous test films of the same type to know where it falls. SMPTE's target on 35-PA is an excellent one that can provide an abundance of information if one knows where to look for it. And, if one reads the RP-40 document, it is all spelled out there for one. We now have ovals in the corners for CinemaScope, more targets, high resolution lines (85 lines/mm) jump indicators, shutter ghost patches, dimensional lines and that lovely checkerboard pattern that not only lets us have a nearly 50% transmission (good for simulating the actual heat conditions) but also allows one to measure the actual jump and weave in the system since the squares are of a specified dimension. I can't think of any test film that packs as much punch in it! I only wish it was reliable in the steadiness department.
As to pulling the aperture plate...That does NOT necessarily point to the projector as the culprit for image unsteadiness. For instance, if the film is slit improperly (it varies from say 34-36mm to make it dramatic) then the perforations and image will move together since the projector references the image based on the edge of the film. It isn't the projector's fault the film varies in width. Likewise, if the perforations are mispunched (vary in location from frame to frame and/or respect to the reference edge of the film) then the perforations and image will move in unison but the image will weave on a projector that uses a reference edge. The reason for this is that the cameras (and telecines) use the perforations to register (i.e. pin registered) so the image will always be locked to the perforations, regardless of where the perforations fall with respect to the edge of the film. How can you tell if it is the projector or the film? If you are using a loop, it is normally pretty easy to spot bad test film....if you can predict the splice (before it comes back around into the projector) due to the same movement alway "x" seconds before the splice, it isn't the projector's fault. If the movement is periodical then often it is a projector issue. Sometimes the hardening process of lateral guide rollers will cause them to warp slightly (Simplex is more prone to this due to the thinner material) and if the period of weave is same as the period of the roller rotation (and please tell me they are indeed rotating) then you have found your culprit! Intermittent related movement tends to be much more violent, including misalignment between the lateral guidance system and the intermittent sprocket. Steve ------------------ "Old projectionists never die, they just changeover!"
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Steve Guttag
We forgot the crackers Gromit!!!
![](http://www.film-tech.com/ubbmembers/268e.gif)
Posts: 12814
From: Annapolis, MD
Registered: Dec 1999
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posted 03-25-2002 01:46 PM
John,I just checked my test film...on the 35-PA the "Eastman" label is there on the edge. For the Schneider film and color out of DEL labs they were not labled as such. The Schneider film did have "AGS" on the edge (Agfa?) and the magenta film was labelless. Steve ------------------ "Old projectionists never die, they just changeover!"
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Steve Guttag
We forgot the crackers Gromit!!!
![](http://www.film-tech.com/ubbmembers/268e.gif)
Posts: 12814
From: Annapolis, MD
Registered: Dec 1999
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posted 03-25-2002 03:51 PM
John,You can take any current 35-PA and find the problem, I haven't had any good stuff in the past 12 months. Steve ------------------ "Old projectionists never die, they just changeover!"
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