Film-Tech Forum ARCHIVE: White Flash on scope films issue

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Posted by Richard Greco (Member # 2032) on 03-10-2004, 07:49 AM:

I'm not sure how to describe this so here goes...

On Most scope films in a specific projector I see a strange thing at EVERY shot change in the particular film. A thin white line flashes right at the TOP of the screen. It looks like a lab splice but it isnt

Depending on the framing of the show, I can see it through the top masking. It doesn't show on screen. I DO however, see it on the reflection on the wall in the booth. At every different shot change I see this thin white flash. Any ideas on what this is or what is causing it?

Since it doesn't show in the auditorium unless you are looking at the top masking, I'm not that concerned. BTW, the reason why the film is on the top curtain anyway is b/c the plate is cut wrong. If it helps, I run Century S/A projectors. Cant remember what the lamphouse is.

Thanks

Posted by Jeremy Fuentes (Member # 2135) on 03-10-2004, 07:58 AM:

Is that on The Passion? Because I've seen it to. I just adjust the framing knob slightly, and it goes away. Don't know what it is, but it shows alot on Passion.

Posted by Chris Hipp (Member # 1788) on 03-10-2004, 08:13 AM:

This has been discussed several times recently. You are seeing the negative splices. If you have top masking you might be able to bring it down some, but chances are you will just need to get that plate re-cut.

Posted by Richard Greco (Member # 2032) on 03-10-2004, 08:22 AM:

Most notably it is on The Passion and I saw it on Peter Pan too.

Negative Splices at every shot change? I havent seen it on Starsky & Hutch yet but I may not see it as much b/c I dont see that projector as much as the one in question.

Posted by John Pytlak (Member # 331) on 03-10-2004, 08:23 AM:

Lots of discussion in other threads about visibility of some negative splices, especially for "scope" films, and "Passion of Christ" in particular. Splice dimensions are specified by SMPTE Recommended Practice RP 111. Projectable image area is specified by standard SMPTE 195. If a negative cutter has poor technique or uses the wrong type of splicer, the cut negative may have splices that are visible within the 0.825 x 0.690 inch projectable image area specified by SMPTE 195.

Projectable image area is defined primarily by the black masking around the screen, with the projector aperture being cut to allow a slightly oversized image onto the black masking to avoid seeing the "fuzzy" edges of the aperture.

For a picture that has distracting negative splices, you can consider cropping the image somewhat -- use a slightly shorter focal length lens to enlarge the image, then cut a new aperture plate to just slightly overshoot the 2.39:1 aspect ratio defined by the screen masking. But for properly spliced anamorphic films, definitely try to use the area specified by SMPTE 195.

http://www.kodak.com/US/en/motion/newsletters/pytlak/spring2001.shtml

http://www.kodak.com/US/en/motion/newsletters/pytlak/oct2001.shtml

Posted by John Hawkinson (Member # 1135) on 03-10-2004, 09:05 AM:

For people who may not have a stock of extra lenses of the right focal length lying around, plus the time and know-how to cut a new plate, a quick-and-dirty workaround is to order an "undersize" aperture for the projector.

If you ever end up showing negative splices, or old movies with weird registraiton problems, etc., you can just swap in the undersize aperture for that film. You'll lose the sharp edging of the masking, so it's your call which looks better, but it's fast and cheap.

--jhawk

Posted by Frank Angel (Member # 248) on 03-10-2004, 10:45 AM:

Usually projection lenses are manufactured in 5mm focal length increments; if your current lens is producing near-perfect image size, then in all likelihood, then, depending on the throw, espeically at shorter throw distances, the next increment smaller FL (greater magnification) would most likely produce an image that would be very much larger than what is needed to just cover the neg flashes and you would need to cut a plate that would crop much to much image in order to mask the picture spill that would be caused.

There was talk in the another thread about being able to take an aperture plate and hammer out the metal in such a way as to extend the edge enough to block the neg flashes. Although I have never done this myself, I was fascinated by the idea and would try it myself if I ever had the need make a slight reduction of aperture size, as in this case.

Now if you are very lucky, you may have one of the newer Schneider lenses that have a kind of zoom element that allows for up to a 7% size increase or decrease as is needed for a perfect image fit without the need to cut aperture plates at all, in most cases (oh that all lenses had this capability). This would indeed be the perfect fix for this type of problem.

Frank

Posted by Michael Schaffer (Member # 1204) on 03-10-2004, 11:17 AM:

All of the above said is true, but in many cases you see the negative splices just because the projectionist hasn't framed properly. Most likely, not thread in frame, and then "corrected" the frame imprecisely with the frame knob. But then a lot of cinemas are not installed properly with true formats, then you might indeed have a problem that has to be corrected.

Posted by Mark J. Marshall (Member # 1409) on 03-10-2004, 11:33 AM:

If editors would just try to be consistant when working on one film by keeping the splices either on the top OR the bottom of the frame for the duration of that movie, it would solve a lot of problems. My problem with Passion is that the splices are visible on the top in the beginning, then later they move to the bottom, which necessitates re-framing. We also had this exact same problem with Peter Pan.

I guess Passion won't be up for any "Best Editor" awards.

Posted by Michael Schaffer (Member # 1204) on 03-10-2004, 11:53 AM:

The Best Editing Award has nothing to do with negative cutting. The editor is the person who decides in what sequence the footage is edited, the negative cutting comes at a different stage in post-production.

Posted by Scott Norwood (Member # 30) on 03-10-2004, 11:56 AM:

My understanding is that the reason why the negative splices drift from reel to reel is that most films are printed on bi-directional printers, and the image may thus be shifted slightly too high or slightly too low depending on which direction the printer was running when the reel was printed. Apparently this is done to save the time and wear and tear on the internegative that would result from having to rewind it after printing each reel. I'm pretty sure that John Pytlak posted about this at one time.

Negative splicing is done by the negative cutter, not by the film editor, so it isn't the editor's fault that the negative cutting was done poorly.

Posted by John Pytlak (Member # 331) on 03-10-2004, 12:29 PM:

The KS-1870 perforations used on print film have a height of 0.078 inches. The BH-1866 perforations used on the printing negative have a height of 0.073 inches:

http://www.kodak.com/US/en/motion/support/h1/sizesP.shtml#perfs

quote:
Perforations
Why All the Sizes and Shapes?
In the early days of 35 mm motion pictures, film perforations were round. Because these perforations were more subject to wear, the shape was changed to that now known as the Bell & Howell (BH) or "negative" perforation (Figure 41). This modification improved positioning accuracy and was the standard for many years.

So on a bi-directional printer, where the negative is printed both heads-to-tails and tails-to-heads, there can be a 0.078-0.073 = 0.005 inch shift in vertical position.

Most cut camera negatives would be printed heads-to-tails on a wet printer to make the master positive. But even if a bi-directional printer was used, splices that conform to SMPTE RP 111 would not be visible on screen.

Posted by Brad Miller (Member # 2) on 03-10-2004, 02:36 PM:

Yet another reason to dislike Deluxe for bi-directional printing.

Richard, you're going to have to get your tech in there. The best solution is to have the masking adjusted slightly and a new plate cut. Alternatively for more money you can get a new lens one step shorter and cut a new plate, but then you are cropping more image. If possible, bringing in the top or bottom masking a bit with a new plate is the best solution. That problem will always plague you in that particular auditorium until something is done.

Posted by John Pytlak (Member # 331) on 03-10-2004, 02:53 PM:

Bi-directional contact printers have been a lab "workhorse" for many years. MANY labs use bi-directional printers, even Technicolor:

http://www.rtico.com/bhp/6131spc.pdf

http://www.ctmsolutions.com/debrie_les_produits.php?id=2

Technicolor now has a new "behind the scenes" walkthrough tour on their website:

Technicolor Services

Here is Deluxe Labs site:

Deluxe Film Labs/

And for "Down Under", here is Atlab:

Atlab Australia

Posted by John Walsh (Member # 168) on 03-10-2004, 07:29 PM:

It seems "Passion" has more bidirection 'slop' than other prints. I was watching it and saw the white line, so I corrected the framing. At the next reel chnge, it was visable again. On some reel, I could see it at the top and bottom. We've never had that happen before, so I doubt we're overshooting.

Posted by Dominic Case (Member # 1830) on 03-10-2004, 08:50 PM:

quote:
Yet another reason to dislike Deluxe for bi-directional printing.

Brad, you're going to have to dislike just about every release printing lab if you don't approve of bi-directional printing. [But then I suspect you do;-)] Bell and Howell first made the bi-directional "Model E" printer in, I think, the 1950s. That machine has been superceded many times of course by now, but the principle is as old and well-established as that.

The standards and tolerances for splices take into account the variability that John calculated. If everything is done according to standard there are no problems. Howewver, if splices are a little too wide, then they will stray into the frame, and may be seen either at top or bottom depending on the printing run.

The same applies with the specific projector that Richard mentions in the start of this thread. If the aperture plate is the correct width, it will allow for the tolerances in splices and in printing. If it's too high, it will show the splice.

Except in digital intermediates, there is a "lab splice" at every shot change in a film.

Posted by Daryl C. W. O'Shea (Member # 1303) on 03-10-2004, 09:06 PM:

I'd have to agree with that. Being against bidirectional printing is plain stupid. Disliking incompetent or lazy negative cutters would be more appropriate.

Posted by Brad Miller (Member # 2) on 03-10-2004, 10:49 PM:

Dominic, come visit the US and take a look at some of the crap Deluxe Hollywood is cranking out on a weekly basis. Then maybe you will see where I am coming from with my annoyance from those guys. Regardless, only Technicolor seems to truly be able to print a pleothra of dupes without dirt and end of reel damage showing up on the negative. If this is not attributed to bi-directional printing, then fine. I still maintain the loop cabinet is a superior way of film handling.

Posted by Dominic Case (Member # 1830) on 03-10-2004, 11:28 PM:

quote:
Dominic, come visit the US and take a look at some of the crap Deluxe Hollywood is cranking out

Thank you Brad, I can see both DeLuxe and Technicolor product in this country (we don't get all the printing work [Frown]

). And I've been to the US many times, and I've seen the insides of at least half a dozen labs, including the majors that you mention. Loop printing as well as bi-directional printing is alive and well in all the release printing labs.

I was under the impression that your complaint in this thread was about the variability of pitch and frameline positioning in prints: now I see we're discussing dirt and damage.

Posted by Brad Miller (Member # 2) on 03-11-2004, 02:43 AM:

It's not JUST dirt and damage...

Since you have made the rounds perhaps you can answer this simple question: why, why, why does Deluxe Hollywood prints have such godawful registration? I mine as well have a gorilla jumping on top of the projector.

Posted by Michael Schaffer (Member # 1204) on 03-11-2004, 02:53 AM:

Maybe it is not the print, but the type of projector which you prefer, Brad. Sorry, just couldn`t resist...

Posted by John Pytlak (Member # 331) on 03-11-2004, 08:27 AM:

Most film labs have a contact person for quality control, who would welcome constructive feedback on any print issues. You need to provide specific information, including the title, version, and print/reel number, and a clear explanation of the problem (send a photo of any physical problems like fogging or a bad splice), and a return address and contact information for follow-up. Here is a link to the Association of Cinema and Video Laboratories membership directory, with contact information:

http://www.acvl.org/members.htm