Film-Tech Forum ARCHIVE: Pulsating picture/sound?

This is topic Pulsating picture/sound? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=006404

Posted by Don E. Nelson (Member # 1049) on 07-27-2004, 05:35 PM:

I went to see The Notebook, last week at a 2 year old Regal Theatre. Approx. Reel 3 was pulsating very slowly, the sound would slowly go down 3db, as the picture was jumping around and dimming, and then snap it was good to go until 2-3 min. and the same thing happened again. Strangest thing I ever saw. One reel only,... what do you suppose caused this?

Posted by Brad Miller (Member # 2) on 07-27-2004, 05:54 PM:

One of those reels with 3 lab splices and lab fogging in it, which according to some people "can never happen", but I see it at least twice a year. The reel should have been replaced.

Posted by John Pytlak (Member # 331) on 07-27-2004, 06:33 PM:

I agree with Brad that it may be a reel that was printed on raw stock spliced together from short ends, especially if the pulsation was bluish in color (safelight fog when making the splices) and happened at about the same time as any change in the analog sound. If the processing machine operator didn't detect it during high speed inspection, it should have been caught during theatre inspection and make-up, and a replacement reel immediately requested.

Here is the official policy of the Association of Cinema and Video Laboratories (ACVL):

http://www.acvl.org/manual/4c.htm

quote:
In release printing, it is recommended that there be a maximum of two splices per 400 feet of 16mm or 1000 feet of 35mm. These two splices may be insert splices, or one of the two splices can be a raw stock splice. There should never be two raw stock splices in the same reel. It is further recommended that spliced raw stock not be used in trial prints, dailies, TV spots or recording prints. It is customary practices to charge a premium for release prints that have no raw stock splices.

AFAIK, "The Notebook" was NOT printed on Kodak stock.

Posted by Scott Norwood (Member # 30) on 07-27-2004, 07:56 PM:

Would the type of print stock affect the number of lab splices? I know that Kodak print stock is available in both 2000' and 6000' lengths. Do other manufacturers supply the longer lengths as well?

Posted by John Pytlak (Member # 331) on 07-27-2004, 08:29 PM:

It could affect the color of any safelight fogging, which varies with the type of stock and what kind of safelights are used.

Posted by Chris Hipp (Member # 1788) on 07-27-2004, 11:20 PM:

could it simply have been sprocket damage? perhaps it was running is Dolby digital and the perforations were damaged so it dropped into analog, that could account for the drop in volume. I'm sure that is too simple of an explanation though.

Posted by Dominic Case (Member # 1830) on 07-28-2004, 03:46 AM:

quote: Scott Norwood
Do other manufacturers supply the longer lengths as well?

Yes!

2,000, 4,000 and 6,000 are common lengths.

Feature spools come in odd lengths, typically 1400 - 1900 ft. It's impossible not to have lab splices, unless we throw away vast lengths of raw stock.

A printer or processor speed fluctuation might cause what you described. As John Pytlak says, it should be replaced as soon as it's reported.

Posted by John Pytlak (Member # 331) on 07-28-2004, 05:36 AM:

quote: Dominic Case
A printer or processor speed fluctuation might cause what you described. As John Pytlak says, it should be replaced as soon as it's reported.

Yes, that could have happened too. But I suspect some fogging because of the reported change in sound level. And "jumping around" may be associated with a raw stock splice.

Posted by John Pytlak (Member # 331) on 07-28-2004, 12:32 PM:

Here's the Kodak Catalog listing KODAK VISION Color Print Films and the formats and roll lengths:

http://www.kodak.com/US/plugins/acrobat/en/motion/catalog/colorPrint.pdf

quote:
2383
70 mm CAT No. Sales Unit Min. Units
VCP542 2000 ft; On Core KS-1870 822 4206 1 roll 1
VCP542 2500 ft; On Core KS-1870 846 7862 1 roll 1
35 mm
VCP666 1000 ft; On Core KS-1870 169 7481† 1 roll 6
VCP242 2000 ft; On Core BH-1866 852 3581 1 roll 1
VCP666 2000 ft; On Core KS-1870 827 4037 1 roll 1
VCP701 2000 ft; On Core BH-1870 124 6883 1 roll 1
VCP779 2000 ft; On Core KS-1870 187 2241 1 foot 152,000*
VCP666 3000 ft; On Core KS-1870 140 2569† 1 roll 2
VCP779 3000 ft; On Core KS-1870 124 6016 1 foot 228,000*
VCP779 4000 ft; On Core KS-1870 188 5920 1 foot 304,000*
VCP789 6000 ft; On Core KS-1870 873 9773 1 foot 114,000*

Posted by Steve Scott (Member # 630) on 07-28-2004, 01:35 PM:

It was probably off the same negative that our print of 'The Notebook' was struck from. I pulled out a few two foot sections of film from R3 where the entire width of the film was dark green, all around a lab splice.

Posted by John Pytlak (Member # 331) on 07-28-2004, 01:49 PM:

quote: Steve Scott
It was probably off the same negative that our print of 'The Notebook' was struck from. I pulled out a few two foot sections of film from R3 where the entire width of the film was dark green, all around a lab splice.

"Safelight" fog around a lab splice is usually due to the operator taking too long to make the splice, or having the safelight too bright or too close to the raw stock print film. The printing negative is not being fogged.

Shedding New Light on Darkroom Illumination

quote:
SMPTE Presentation by John Pytlak

Posted by Robert L. Fischer (Member # 2424) on 07-28-2004, 03:04 PM:

I noticed something similar to this on a Collateral trailer that came loose in the cans with the Bourne Supremacy. Has anyone else noticed this?

Posted by Steven Jantzen (Member # 2575) on 07-28-2004, 08:33 PM:

0nly on the taxi trailer that came with the terminal [puke]

Posted by Dominic Case (Member # 1830) on 07-29-2004, 03:11 AM:

quote: John Pytlak was the last to post
the entire width of the film was dark green, all around a lab splice.

Not a negative fog then. Dark green would be cyan fog from a red torch on the print stock - not good lab practice.
Fog on the negative would be (a) light, not dark on the print and (b) only in the image area - not right across the entire width of the film.

Posted by Robert L. Fischer (Member # 2424) on 07-29-2004, 04:46 AM:

Oh well, I don't find the Taxi trailer to be very intriguing anyway.

Posted by Antonio Marcheselli (Member # 373) on 07-29-2004, 05:32 AM:

Print fogging?

Until 6 months ago I had to change 1 or 2 reel weekly because they were blu/green/yellow fogged...

Then they stopped, now it is not so common!

Bye
A

[edited for typo error]

[ 07-29-2004, 10:31 AM: Message edited by: Antonio Marcheselli ]

Posted by John Pytlak (Member # 331) on 07-29-2004, 10:07 AM:

These fogging issues can usually be traced to an operator violating the lab's policies on the proper use of safelights. When fogged reels have to be replaced, the source of the problem will be found and "corrected".