Film-Tech Forum ARCHIVE: Question for the pros... WHATS THAT SCRATCH???

This is topic Question for the pros... WHATS THAT SCRATCH??? 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=003249

Posted by Dave Williams (Member # 299) on 03-30-2002, 03:11 AM:

This question has been bugging at me forever now.

I am sure and hopeful that I am not insane, BUT, I am watching on DVD, the Good the bad and the ugly. In this, I am seeing something that I always saw in just about every single scope film during my tenure as a projectionist and manager, Especially the ones from fox..

WHat I am seeing, is at the bottom and/or top of the frame, during angle changes, a line of what could be called static. It appears literally for only one frame, and occurs only at an angle change. I noticed it was very heavy during Star Wars phantom menace.

Does anyone know why this is? It cant be the projector, because it happens only on angle changes. Any clue helpful.

John Pytlak, maybe you might have a clue?

Dave

Posted by Joe Redifer (Member # 3) on 03-30-2002, 03:19 AM:

I know what you are talking about and I would describe it as a negative splice that happens during editing. You should not see this if the movie is properly framed with well-cut aperture plates. If you see this on DVD then it is a BAD BAD and UGLY transfer! Nothing "good" about it!

Posted by Antonio Marcheselli (Member # 373) on 03-30-2002, 04:20 AM:

Joe is right. Are negative spice.

But sometimes I had to misframe a bit some movie because the negative splice was visible (and my aperture plates are right, I've checked them with RP40).

Bye
Antonio

Posted by Joe Redifer (Member # 3) on 03-30-2002, 04:58 AM:

Ooooooh don't get me started on RP40. I'm sure your apertures are fine, Antonio, but never use it to set up framing. Ever. Instead, make a loop out of an old trailer or something that you KNOW is in frame. In the US people can use a good greenband. But if you use RP40 to set your framing, it will be off. It's been a few years since I set framing knobs to RP40, but if you do I believe it makes the image a bit too low, and you will see the negative splices on top of the frame.

Posted by Brad Miller (Member # 2) on 03-31-2002, 04:00 AM:

Yes indeedy, either RP40 is not properly centered, or EVERY other lab conveniently prints exactly the same amount off of centerline. Never trust RP40 for anything other than initial alignment. Once things are set up and perfect, you will have to adjust the framing control just a tad to get it truly in frame.

Posted by Steve Guttag (Member # 268) on 03-31-2002, 08:56 AM:

If you use B&W "RP-40" With BH-1866 perforations (the ones that have rounded sides) then it is reasonable to expect the framing to be off in relation to a release print. The BH-1866 perforation and pitch are only supposed to be used for negatives, which 35-PA is. Unfortunately, that isn't what projectors are running. Projectors expect KS-1870 perforations which have a longer pitch and a positive perforation.

Since 35-PA is used to also set up Telecines which pin-register to BH-1866 perforations, SMPTE made a test film that would "work" for both worlds. I have put forth a posistion paper to the SMPTE that, among other things, requests using KS-1870 perforations as the standard for 35-PA with the short pitch BH-1866 film as a special request for lab use. I believe you will find that the color version of "RP-40" called 35-IQ is on KS-1870 perforations and will more closely represent release prints.

Another thing to note when using test film to register framing for releae prints...some labs use bi-directional printers. As such if one reel was printed in the forward direction and the next reel was printed in the reverse direction, there will be a vertical shift equal to the slop of the sprocket tooth within the perforation so don't expect the framing to be "perfect" all the way through the show no matter how you set it up.

Stev

------------------
"Old projectionists never die, they just changeover!"

Posted by Jerry Chase (Member # 660) on 03-31-2002, 10:39 AM:

"Another thing to note when using test film to register framing for releae prints...some labs use bi-directional printers. As such if one reel was printed in the forward direction and the next reel was printed in the reverse direction, there will be a vertical shift equal to the slop of the sprocket tooth within the perforation so don't expect the framing to be "perfect" all the way through the show no matter how you set it up."

Kinda blows apart that "lock the framing knob" idea, huh?

Posted by Steve Kraus (Member # 476) on 03-31-2002, 11:11 AM:

They ought to have the reels marked for direction of printing and put only like aligned reels together in one print.

Posted by Gordon McLeod (Member # 33) on 03-31-2002, 11:23 AM:

The negative splice issue is one I still get a bit hot under the collar over
That is why the scope apperture has shrunk from the original 715 high down to 690
Hig speed printing required also a wider overlap in the splices for strength and that with bidirectional printing compromissed the image

Posted by Antonio Marcheselli (Member # 373) on 03-31-2002, 01:28 PM:

Joe/Brad,

I just said that my *aperture plates* are right, I didn't frame with RP40.

Bye
Antonio

Posted by Joe Redifer (Member # 3) on 03-31-2002, 05:40 PM:

Antonio-
I know, but others might assume RP40 is the best way to frame.

Jerry-
Steve is just making a pathetic excuse for changeover booths. He is trying to make us all think that framing will be WAAAY off from reel to reel if reels were printed in opposite directions and run on a platter system without someone there to adjust framing at the reel change. This may happen, but it is not enough to notice (unless you have Steve Guttag's robotic precision ). Once I locked my framing knobs down I never noticed the "negative splices" again. And our apertures (most of them) were cut properly.

Posted by Andy Muirhead (Member # 712) on 03-31-2002, 05:53 PM:

This is a fairly common problem in exhibition (and the post's above regarding plates, etc, show why), but i'm AMAZED that it has reared its ugly head on a DVD.

Why did nobody spot this? It's a pet hate of mine, and i had all my plates and masking re-cut to get rid of this problem. It's so easy to spot, why was it missed in the DVD transfer?

Posted by Manny Knowles (Member # 1171) on 03-31-2002, 06:00 PM:

And it's true that Fox movies seem particularly prone to this. My laserdisc of STAR WARS (The original, original one) has visible splices throughout.

------------------
And, hey! Let's be careful out there.

~Manny.

Posted by Gordon McLeod (Member # 33) on 03-31-2002, 06:05 PM:

Actually Joe if your plates are cut to spec then yes bi directional printing will show up especially on scope.

Posted by Per Hauberg (Member # 529) on 03-31-2002, 06:08 PM:

Look for it in all techniscope spaghetti-westerns - a n d for some reason every scope print of Guns of Navarone -- One fat white, single-frame stripe for every scene-chance the whole film trough.
Not very funny to watch.

/p.

Posted by Gordon McLeod (Member # 33) on 03-31-2002, 06:12 PM:

I have often wondered what effects were of wide neg splices on IB printing since the odds of all 3 matrixs haveing exactly thesmae splice widths if they wouldn't be rather oddly coloured

Posted by Joe Redifer (Member # 3) on 03-31-2002, 07:43 PM:

Then I guess all plates should be cut just a tiny bit narrower than "spec" so this problem doesn't rear it's ugly head. If the problem occurs when the plates are "cut to spec", then there is absolutely no reason on the planet that they should be cut that way!

I just said the same thing twice! Cool.

Posted by Paul G. Thompson (Member # 655) on 03-31-2002, 10:38 PM:

Now you gents know why I also cut my scope aperature plates to .690....

Posted by Josh Jones (Member # 447) on 03-31-2002, 10:44 PM:

A lot of anime DVD releases suffer from this also. One that comes to mind is "Gundam Wing." The series was shot 1.33 and the negative jaggs are visible both in the aired version and on DVD.

Josh

------------------
"Film is made of silver, video is made of rust"
'nuf said

Posted by Joe Redifer (Member # 3) on 04-01-2002, 01:18 AM:

Josh: The Japanese are technological gurus, they have incredible musicians and artists, but they have always seemed lacking in presentation.

Posted by John Pytlak (Member # 331) on 04-01-2002, 01:25 PM:

Standard SMPTE 195 now specifies a "scope" image area of 0.825 x 0.690 inches. The narrow overlap negative cement splices originally used for CinemaScope were not as reliable as a wider overlap. But don't blame high speed release printing, as the duplicate negatives used for release printing rarely have splices in them -- the splices you sometimes see are on the original negative.

Another way of hiding negative splices is to conform the original negative as A and B rolls, with scenes alternating between the rolls ("checkerboard cutting"):
http://www.acvl.org/chap3.htm

Splice dimensions are specified by SMPTE Recommended Practice RP 111. The overlap specified for lab splices is 0.049 inches (1.24 mm)(Dimension A), with 0.040 inches (1.02 mm) recommended for minimum visibility on projection.

Scanned image areas for television (e.g., DVD transfers) are specified by SMPTE 96M.

Here's the history of the "scope" dimensions:
http://www.widescreenmuseum.com/widescreen/apertures.htm

The March 1957 SMPTE Journal has PH22.104-1957, the standard for 2.55:1 anamorphic (no optical track), with an aperture size of 0.912 X 0.715 inches. Notice of withdrawal of this standard was in the January 1964 Journal.

The December 1957 SMPTE Journal has PH22.106-1957 for 2.35:1 anamorphic, with an aperture of 0.839 X 0.715 inches. It was unchanged in the September 1964 Journal. The November 1965 SMPTE Journal published PH22.106-1965 still with the 0.839 X 0.715 aperture size.

In the September 1970 SMPTE Journal, a new draft of PH22.106 was proposed, with an aperture size of 0.838 X 0.700 inches, to minimize the flashes at splices. This was republished as standard PH22.106-1971 in the October 1971 issue.

In the June 1976 SMPTE Journal, the two (flat and scope) projectable image area standards (PH22.58 and PH22.106) were consolidated into one standard and renamed PH22.195. The publication of PH22.195-1984 in the October 1984 Journal still had the scope area as 0.700 X 0.838 inches.

The June 1992 SMPTE Journal published a proposed revision, with a scope area of 0.690 X 0.825 inches. In August 1993, the standard was published as SMPTE 195-1993, with the current area of 0.690 X 0.825 inches. So August 1993 is when the two formats became the same width of 0.825 inches.

With the small frame of the 2-perf Techniscope format, the negative splices would be impossible to hide unless A/B roll printing was used.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: +1 585 477 5325 Cell: +1 585 781 4036 Fax: +1 585 722 7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Ken Lackner (Member # 1002) on 04-02-2002, 12:34 PM:

I've heard of locking the framing know. Why in the world would you want to do this, and how is it done?

Isn't RP40 for alignment? So why shouldn't it be used for framing?

Posted by John Pytlak (Member # 331) on 04-02-2002, 12:54 PM:

The 35-PA test film (RP 40)is produced on a pin-registered camera, using the centerlines and projectable image areas specified in standard SMPTE 195, so indeed it should define the projectable image area. But as noted, to also allow use for setting up printers, 35-PA is made on film with negative-type BH perforations, rather than the KS perfs normally used for prints. The BH perf has a height of 0.073 inches, the KS perf has a height of 0.078 inches. Release prints are usually made on continuous contact printers (no registration pins), so there can be a slight vertical shift in release prints from the exact centerline specified in SMPTE 195 of having the frame centerline "nominally" equidistant between two perforations (dimensions J=K), especially on bi-directional contact printers.

Posted by Brad Miller (Member # 2) on 04-02-2002, 04:34 PM:

Ken,

To answer your question, locking the framing knobs is a wonderful technique to ENSURE that ALL of your presentations at the theater, even when you are not there to supervise, are always ran perfectly in frame. Basically here is the argument.

The *typical* multiplex always has at least one "projectionist" who is either lazy, careless or just plain stupid and manages to start up films occasionally out of frame. First, you now have an embarassing start to your theater's presentation, even if he immediately cranks the framing knob to fix it...but did he? Most of us who favor locking the framing controls find that when the framing is rotated to fix a threading error, it is virtually never correct! Negative splices flash on scope films and flat films are commonly rotated to the point of just barely losing the frame line, which means your presentation runs almost a complete perforation out of frame. Completely unacceptable! With no "cheat knob" available, this forces the projectionists to double check their threadings before they hit START. Also, since most projectors alter the upper and lower loop size when the framing is rotated, always starting in frame substantially improves the odds that the loops will not start slapping on something (that scratches the film) after the framing knob has been altered.

So what happens when this same "projectionist" runs a booth with their framers locked? Simple. The guy misthreads the film, although much less often than before (if at all) since he knows the consequences of slacking, the movie starts and it is out of frame, and then the projectionist has to shut the whole thing down and open up the gate to properly thread the film in the gate. (While of course the audience members look at him through the window, something most all projectionists hate.) Meanwhile, most automation systems will announce his mistake by sounding the alarm throughout the building when the prematurely stops the show, further adding to his embarassment. Is this a good thing? Absolutely, because like I said it FORCES the projectionists to pay more attention to what they are doing. As for the presentation, the way I see it if the show starts out of frame, having the framing rotate up/down only to almost always still land out of frame for the duration of the show (and what could be another week's worth of shows after that one) is no better or worse than just shutting the system down for 15-30 seconds while the projectionist does his job.

The other benefit is when you come into the booth to run your shifts (or any other real projectionist), you know that if you thread the machines "in frame" that they will always be truly in frame, and never have to concern yourself about them actually being a bit off.

Now there are people who will claim that every film is printed a little bit off from each other, and that Deluxe's prints have altering framing depending on whether the printing was forward or reverse printed. Now while to the truly anal that may be so, but I can tell you after implementing this practice for a few years I have never seen anything that looked to me like it was out of frame in the least.

It may be considered a "mean" tactic by some, but damnit it works! Anyone who has to have a framing crutch has no business in the booth.

[/rant]

Posted by Joe Redifer (Member # 3) on 04-02-2002, 06:25 PM:

It really does work. Before I met Bad Brad about 4 years ago, I did not lock my framing kobs. We had a guy who would thread out of frame at least once, maybe twice a day. It would not be uncommon to come in and see the knobs in completely different positions than the day before. Then I set the framing up perfectly and locked it down on each projector. Of course I was met with abrasive attitudes on the subject, which is to be expected. A few days went by without any problems, then one day I come in to find a note written in the booth log that the day projectionist threaded a projector out of frame and it took him 20 minutes(!) to fix! I of course heard complaints that it wouldn't have taken that long if the framing knobs had not been locked. But that guy hardly ever threaded out of frame again, and he stopped complaining of the locked knobs since he started threading correctly.

Posted by John Pytlak (Member # 331) on 04-03-2002, 06:46 AM:

Brad said: "Now there are people who will claim that every film is printed a little bit off from each other, and that Deluxe's prints have altering framing depending on whether the printing was forward or reverse printed."

As I noted, the height of the negative BH perf is 0.073 inches. The height of the print film KS perf is 0.078 inches. So, even with a bi-directional contact printer, the vertical shift in the image centerline from the "nominal" equidistant between the perfs should not exceed 0.078 - 0.073 = 0.005 inches, or only about 1% of the image height for 1.85:1 "flat". If the centerline shifts more than that, an error was likely made during optical printer setup or in composing the image in the camera viewfinder.