Film-Tech Forum ARCHIVE: Terminologies?

This is topic Terminologies? 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=001611

Posted by John Wilson (Member # 269) on 10-28-2000, 07:33 AM:

Just curious...

What did I.B. stand for in I.B. Technicolor.
also...what did LPP stand for?

Thanks

Posted by John Walsh (Member # 168) on 10-29-2000, 05:38 AM:

I.B. stands for "imbibition." While it is usually used to describe Technicolor's release printing process, it techinally means:

"Depending on the wetting properties of the fluids there are essentially two different types of displacement in two-phase flow in porous media. ..... we are considering drainage displacements where a non-wetting invading fluid displaces a wetting fluid. The opposite case, imbibition, occurs when a wetting fluid displaces a non-wetting fluid. The mechanisms of the displacements in drainage and imbibition are quite different and the two cases should not be confused. Typically, slow drainage is characterized by piston-like motion inside the pores where the invading non-wetting fluid only enters a pore if the capillary pressure is equal to or greater than the threshold pressure of that pore. The threshold pressure corresponds to the capillary pressure in the narrowest part of the pore. However, in imbibition at low injection rate the invading fluid will enter the most narrow pores before any other is considered."

See: http://www.fys.uio.no/~eaker/thesis/node10.html

For a good explanation of imbibition as it applies to motion pictures, see Marty's excellent web page: http://www.widescreenmuseum.com/oldcolor/technicolor1.htm

Or: http://home.att.net/~B-P.TRUSCIO/COLORDEX.htm

Or, for a quick explanation: http://www.tlcdelivers.com/tlc/crs/Bib0352.htm

Don't know "LPP."

Posted by David Hitt (Member # 294) on 10-30-2000, 06:30 AM:

If memory serves, LPP means "Lowfade Positive Print" and refers to a Kodak print stock having improved dye stability. LPP replaced SP ("Special Process"), which was a developing process that improved dye stability.

David

Posted by Bruce McGee (Member # 131) on 10-30-2000, 10:51 AM:

So far so good for the LPP stocks.

I have several 1982-1983 LPP prints that are holding up with regular use and the blacks are still black, and the colors are still vibrant.

As for Vinegar Syndrome, I have a single 35mm feature made in 1983 on tri-acetate stock that has VS in reel one only, This print sat unused in a hot warehouse for 15 years. Then I got it. The only thing that I notice on the VS reel is that there is a slight color shift on the side of the film that was up. The print was stored flat on cores.

FilmGuard took care of the smell enought so that the only time that I can smell the film is when it is being run on the mighty Holmes. R's 2-5 dont smell at all, and have no image problems.

My IB prints are stunning.

Posted by Scott Norwood (Member # 30) on 10-31-2000, 06:52 AM:

My IB prints are stunning, too, with the exception of an odd reel of the 1998 GWTW reissue, which is just horrible. I do have a slightly warped IB print that is otherwise good; it doesn't focus properly from edge to edge (this is a 16mm print, too). Periodically rewinding it and changing the orientation (heads-out/tails-out, emulsion-out/emulsion-in) seems to help. I keep meaning to try FG on it as well. I'm also tempted to try "Film Renew," which is supposed to help warping, but I haven't yet talked to anyone who has actually used it.

Posted by John Pytlak (Member # 331) on 10-31-2000, 09:54 AM:

Bruce: The acetic acid vapors from vinegar syndrome can adversely affect dye
stability. If the print was never moved in 15 years of hot storage, the acid vapors could have affected the dyes on one side more than the other if the concentration was uneven.

As you know, heat and humidity and unvented storage aggravate vinegar syndrome.You can slow the progress of vinegar syndrome by storing your prints cool and dry, and using either vented storage (no sealed cans/cases) or Molecular Sieves in sealed containers:
http://www.kodak.com/country/US/en/motion/support/technical/vinegar.shtml
http://www.kodak.com/country/US/en/motion/support/technical/molecular.shtml
http://www.kodak.com/country/US/en/motion/about/environment/mole.shtml

Glad (and not surprised) to hear that Eastman LPP color prints (5384) almost 20 years old still look so good.

David Hitt: "SP" designated "short process", which was the edgeprint on 5383 using the higher temperature ECP-2 process. "LPP" was the original edgeprint used on the EASTMAN Color Print Film 5384 with improved dye stability intended for process ECP-2.