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Bad telecine transfer


George Ebersole

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Some films in my DVD collection have images that shake and "waver" or move. I'm guessing it's the screen moving as the image is projected on it.

 

But, I was wondering if anybody knew any other explanation.

 

Just to clarify, it's as if there's air being blown behind the screen, and image "wavers" and fluctuates. Most movies I have don't have it, but there's a few that suffer from this.

 

Thanks for any reply.

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No real telecine uses a "screen" to "project" on, it is possible that the film had issues with shrinkage that the mechanism of a Spirit or Cintel telecine had problems with, films like that would never make it through a projector.

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"shake" or weave is common in transfers that don't use pin registration or some kind of active stabilization mechanism (whether in-transfer or in post).

 

Breathing, where the film is going in and out of focus, could be from shrinkage like Rob says. Are you seeing this in a consistent pattern, or is it only at cuts? With telecine-like machines that use constant motion and a line scanner, you can get some warping of the image at cuts. This will look like a blur or smear, usually across only part of the frame, though.

 

It's also possible, since you're using DVD as a reference, that the problem is in the encode and not the transfer from film. I've seen some truly awful discs made by the major studios (looking at you, Warner). I mean really terrible: aggressive noise reduction, terrible compression, etc. The compression on DVD (and Blu-ray) is temporal as well as spatial, so it's not unusual for the only good looking frames to be I-Frames (usually every 12-15 frames), with the rest looking kind of meh. This could cause an effect that looks like the picture is going in and out of focus.

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Any line-array telecine can create wobble that looks a bit like rolling shutter wobble on a modern CMOS camera.

 

One early device by Marconi had no drag or friction of any kind in the tachometer sprocket that was used to sense film speed, and as such was prone to wobbles in the timing when handling film in less-than-perfect condition.

 

P

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Thanks for the replies. It happens mostly with older DVDs in my collection. And yeah, I figured that by the time DVD technology came about that film would be scanned in and then digitally reconstructed for the DVD format. But some of the older films in my collection show warbling.

 

It's not film shake though. That is a pin issue, but this isn't a matter of the film gently bouncing side to side. It's the image ... warping a bit. Like someone had a can of air or a compressor, and was blowing behind the screen or something.

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We can probably only be more definite if you can upload a sample somewhere, but the appearance of wobble caused by timing drift in a line-array telecine is fairly organic in appearance and probably fits your description.

 

P

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Having worked with a Marconi B3410 telecine for 22 years, I know it is sensitive to adhesive residue on the back side of the film. In those days, a lot of television was shot on 16mm colour reversal, edited on Steenbeck and the film with many tape splices put on telecine. If the film was kept in a hot location, the tape would 'bleed' and adhesive would be all over. Every time this adhesive unstuck on the feed side reel, you would get some wave effect since the smooth passage of the film over the line-array CCDs was disturbed. Even the modern Shadow telecine I have now is not entirely free from this problem.

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And yeah, I figured that by the time DVD technology came about that film would be scanned in and then digitally reconstructed for the DVD format. But some of the older films in my collection show warbling.

 

Believe it or not, in 2014 we still get the occasional master on BetaSP from telecine work done in the 80s, for commercial feature film DVD releases. Usually we try to persuade the client to find a newer master if they can, because these transfers often have the issues you've described. Not to mention 25+ year old Beta SP tapes are rarely dropout-free. But, sometimes the film is lost and all that's left are those transfers.

 

I think in the early days of DVD the studios were just cranking out whatever they had on tape, to start filling shelves.

 

-perry

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A good example is on my "Three Amigos" DVD. Between 38 minutes and 42 minutes the various elements in the image move and shake on their own, independent of one another. It's really strange.

 

I've got a number of other DVDs with the same issue, but I can't remember all of the instances.

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I've got a number of other DVDs with the same issue, but I can't remember all of the instances.

 

If they're older discs, it could also be encoding issues. The first DVD I ever bought was 2001: A Space Odyssey. It was unwatchably bad compression. Space wasn't solid black, it was this crazy mosaic of macroblocking! And the ship interiors were just swimming in compression. Truly awful.

 

In the early days of DVD the compression tools weren't so great. in about 2004/2005, there was a new generation of encoders and quality improved dramatically, giving you exponentially better picture at the same bit rates. It wouldn't surprise me if what you're seeing is related to heavy handed noise reduction, which was a technique used a lot in the early days of DVD to keep the encoders from totally freaking out on noise in the master tapes. Remember that back then almost all compression was done in hardware, direct from tape, not in software like it is today.

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That's interesting. It shows you how out of the loop I am because I always thought the data was run through a number of decks, like cleaning an audio tape.

 

I guess the idea was that the warping wouldn't be noticeable on a CRT so the people who did the encoding let it go, but on any flat screen you can see it clear as day.

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Just a bugbear of mine - actually in the mid-2000s, there were very good software MPEG-2 encoders which were gigantically better than the hardware. Unfortunately it was an emperor's-new-clothes situation with sophisticated advertising campaigns for the expensive hardware encoders (this sort of thing happens constantly). The software has almost always been better, just slower.

 

I was involved in the launch of a small satellite TV station in the UK in about 2004 for which we used Tsunami to prepare material for broadcast. This was an unusual situation as invariably people would use hardware boxes and do it in realtime. It was viewed as unorthodox and took quite a bit of persuading to get the uplink people to allow us the kind of technical access we needed, as well as a bit of back-and-forth on encoder settings. After a reasonable amount of prep and test, it was shown to work much better than the alternatives - we got image quality in a very small amount of bandwidth that took much more bandwidth for others to do.

 

Of course this could only work on a station that was essentially a video carousel, but it worked very well. Nobody believed me and I was never allowed to do it again.

 

P

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Just a bugbear of mine - actually in the mid-2000s, there were very good software MPEG-2 encoders which were gigantically better than the hardware. Unfortunately it was an emperor's-new-clothes situation with sophisticated advertising campaigns for the expensive hardware encoders (this sort of thing happens constantly). The software has almost always been better, just slower.

 

These are the second generation encoders I was referring to - tsunami, cinemacraft, etc. We were pretty early adopters of both, even though we had one of the better hardware MPEG encoders. Speed wise, you couldn't beat the hardware at first, but you got better quality at lower bit rates so it was worth the tradeoff if the schedule allowed.

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I'm watching the 1962 production of "Mutiny on the Bounty", the two disk special edition version. It's presented in 2.76:1 format, which is nice, but there does seem to be an awful lot of compression going on. The image is clear, but it's pixelated between colors.

 

I'm wondering why older films that are shot on 65mm aren't given the same kind of treatment in terms of definition that more contemporary films get. I'm guessing it's a matter of cost.

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It depends on a lot of things.

 

Many early DVDs were made from the same masters as the VHS tapes had been, which often meant Betacam SP. This isn't really good enough to produce a really good DVD, to the limits of the format, in the same way that a modern movie might derive its DVD from the downscaled (and appropriately colour-reprocessed) output of the same grading process that produces the cinematic release. Obviously the difference between those approaches is night and day, and the MPEG-2 codec will do far better with better data.

 

I was once involved in putting some grading equipment into the remastering department of a big LA studio. While I was there, they were working on the DVD release of a Cinerama film, using the grading gear to smooth out the joins and producing a master of staggering resolution and beauty. There does seem to be some appetite for restoring at least the better-known stuff to the highest possible standard, if only because they want to do a blu-ray (or internet-distributed HD stream) of it, which also enables a far better DVD.

 

Which titles actually get this treatment will clearly be a commercial decision, although Blade Runner didn't have a decent DVD for years.

 

P

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I can see that. My original "The Right Stuff" DVD was a dupe off of the old master for the VHS release. The newer disk is night and day compared to the original disk (which I donated to the library).

 

Admittedly the audience for the 62 version of Bounty has probably dropped off the radar, but it's still an exceptionally well put together film, and deserves a little better. I mean it got a two disk special edition treatment with the film's full original aspect ratio, but compared to any film made in the last ten years that's been put on DVD, it is a little painful to watch.

 

The thing was shot on 65mm, but it looks like a dupe of a 16mm print. That's another beef I have with either studios or whoever makes the final decision on how a film is to be released to the home video market. Nearly every foreign film I've purchased from overseas on DVD has a sharp crisp image from a fresh print.

 

But it seems like American films (and a few UK productions) get the baseline "cheapest possible way" treatment (it's not just movies either, but that's another thread for another time). On my "Excalibur" DVD you can clearly see specks of dirt here and there in a few frames, even though there's commentary from the director on that edition.

 

I guess I'm just puzzled as to what the criteria is for marketing a film for home video distribution.

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You can transfer an old movie from any number of elements, the original negative, a contact-printed interpositive, a dupe negative (contact-printed or optical-printed), or a release print. And any of those elements can have problems -- aging, dirt & dust, damage, etc. And for an old title, all of those options in terms of source materials may not be available to the company doing the home video release.

 

Compound this with the budget for digital restoration work after the scan is completed, which may be limited (and is usually based on how much money they think they can make from the home video release). And also factor in that some cinema purists have issues with overly "fixed" or "cleaned up" restorations that remove too much grain or add too much sharpening, or make the colors too modern and saturated.

 

65mm movies and 3-strip Technicolor movies are unique problems since it is hard for most home video companies to deal with the original format, even if they had access to it -- they don't have scanners that can deal with 65mm so they have to use a 35mm element, and with 3-strip Technicolor, they can't deal with scanning three b&w negatives (all having shrunk at different rates) and re-registering the three images to recreate color without fringing problems. So in those cases, you are likely to see a telecine transfer of a 35mm release print or dupe negative unless someone does a major restoration.

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You can transfer an old movie from any number of elements, the original negative, a contact-printed interpositive, a dupe negative (contact-printed or optical-printed), or a release print. And any of those elements can have problems -- aging, dirt & dust, damage, etc. And for an old title, all of those options in terms of source materials may not be available to the company doing the home video release.

 

Compound this with the budget for digital restoration work after the scan is completed, which may be limited (and is usually based on how much money they think they can make from the home video release). And also factor in that some cinema purists have issues with overly "fixed" or "cleaned up" restorations that remove too much grain or add too much sharpening, or make the colors too modern and saturated.

 

65mm movies and 3-strip Technicolor movies are unique problems since it is hard for most home video companies to deal with the original format, even if they had access to it -- they don't have scanners that can deal with 65mm so they have to use a 35mm element, and with 3-strip Technicolor, they can't deal with scanning three b&w negatives (all having shrunk at different rates) and re-registering the three images to recreate color without fringing problems. So in those cases, you are likely to see a telecine transfer of a 35mm release print or dupe negative unless someone does a major restoration.

 

But to me that seems like a software issue. If you have a three stripe original neg of ... I don't know .... "Meet me in St. Louis", and each color shrank differently, then it seems like the software ought to be able to detect a variance in image size, and then match it up frame for frame when piecing together the three different colors. I think Disney has the computer horsepower to pull off those kinds of reconstructions, which I think is why their restorations are simply fantastic.

 

But like you say, it comes down to how much time and effort you're willing to put in for a payoff that you're not sure about.

 

Me, I'm not a cinema snob. Anything that increases the definition or improves the print is good in my book. I'm all for making the image as compelling as possible.

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