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Topic: Wavy lines

Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 04-16-2002 03:20 PM

I can answer that question for you John, no. The print I screened of Changing Lanes had a 5-10 second burst of the wavy "interference lines" once on every reel and it was on a variety of images.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-16-2002 03:30 PM

Any particular place in the reel? Start-Middle-Finish?

Did the bars "roll" up and down through the image, or did they hang in the same place (e.g., aligned with the perfs)? Were they neutral, or did they seem to have some coloration?

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 04-16-2002 03:40 PM

Neutral, rolled, randomly throughout the reel (never in the same place).

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99

posted 04-16-2002 03:56 PM

I wish this effect could be videotaped. Well maybe it can but I've never tried. It's hard to tell if they are rolling up or down, they kind of fluctuate and could be perceived to be rolling either way it seems.

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David Stambaugh
Film God

Posts: 4021
From: Eugene, Oregon
Registered: Jan 2002

posted 04-16-2002 04:00 PM

I just saw the movie again, only at a different theater. No wavy lines this time, none at all.

Brad's characterization of these rolling bars is about right, although I think 5 secs. would be the longest I've ever seen them last. They fade in, reach a peak, then fade out. They have kind of a gray shading, and nothing in the image is being obscured. They roll rapidly from top to bottom of the image (at least that's what it looks like, might be an illusion). They really do look like something from a video display, not filmlike.

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 04-16-2002 04:02 PM

At one point when I was in Colorado I found a green band with this phenomenon. My intention was to try and do a crappy "shoot the screen from the port window" 10 second video that could be downloaded as an example. Only problem, I don't have a video camera, couldn't find anyone with a video camera and I have no idea where I put that strip of film. (I highly doubt anyone would come running after me for duping the green band, but I didn't want to shoot off 10 seconds of a movie for copyright reasons.)

As to the rolling, no it's not rolling wildly, but there is definite rolling motion to it.

Not to intentionally keep slamming this one lab, but has anyone ever seen this phenomenon from a non-Deluxe Hollywood print? I haven't.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-16-2002 09:55 PM

We're letting the lab know about the concern, and will help them investigate the cause. Thanks.

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Joseph Pandolfi
Expert Film Handler

Posts: 213
From: Milford, CT.
Registered: Nov 1999

posted 04-19-2002 09:14 PM

Thanks Joe & Brad for bringing this topic up. I noticed this a lot about a year ago, not to much now and mostly at a trailers green band. Once I was screening a print and this occured so bad on a outdoor scene that it looked like dusk for about a second before it hit a lab splice.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-22-2002 08:16 AM

Joseph said: "...it looked like dusk for about a second before it hit a lab splice."

Thanks for another clue to the cause. Does there seem to be a correlation with the lab splice? That is, does the banding tend to occur just before a lab splice?

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99

posted 04-22-2002 10:10 AM

It is not uncommon to see horrible color shifts before and after a lab splice due to the "rush rush rush" mentality of some labs that is destroying the quality of film. Of course those reels should be replaced right away. But the wavy lines are usually never around a lab splice and look totally different.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-22-2002 11:14 AM

Joe --- I was looking at the possibility that somehow the lab splice caused a slight disruption in the speed of the film as it went past the printer aperture.

The discoloration you mention is likely due to fogging from the darkroom "safelight" used to illuminate the splicer to aid the operator in making the lab splice --- sometimes it may take the operator a few seconds longer to make the splice, so some fogging occurs. It's usually colored blue or cyan. Severely fogged reels will be normally be replaced by the lab.

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David Stambaugh
Film God

Posts: 4021
From: Eugene, Oregon
Registered: Jan 2002

posted 04-22-2002 11:17 AM

So maybe we should be looking for correlation between the wavy line syndrome, and a lab splice, both on the same reel, even if they aren't near each other. ?

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 04-22-2002 11:28 AM

David asked: "So maybe we should be looking for correlation between the wavy line syndrome, and a lab splice, both on the same reel, even if they aren't near each other. ?"

Yes. I was following up on Joseph Pandolfi's observation that the banding showed up just before a lab splice. Banding within a minute or so of the splice could be a good clue.

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David Stambaugh
Film God

Posts: 4021
From: Eugene, Oregon
Registered: Jan 2002

posted 05-05-2002 06:47 PM

The "Spiderman" print I just saw had the wavy line syndrome in both reel 4 and reel 5, roughly at the mid-point of each one. I didn't notice any lab splices. Aside from that the print was in perfect condition.

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Darryl Spicer
Film God

Posts: 3250
From: Lexington, KY, USA
Registered: Dec 2000

posted 05-05-2002 07:43 PM

I noticed this same effect on changing lanes also. During darker scenes. I did not notice them in the print of Spiderman that I screened.

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