DI Resolution

[Keith Walters]

While ultrasonic splices on polyester stock are quite good, they aren't perfect either, better than tape splices, but I know projectionists that splice them out or put a tape splice over them, just to be safe

The splices made by ones I worked on could just about support my entire body weight, as occasionally demonstrated to disbelieving visitors. However, the splicers have to be well-maintained to do this, and probably like just about everything else in the film industry, if the deficiencies ain't visible, they ain't ....

 

I'm not entriely sure why the release stock has to be that strong though.

[Keith Walters]

From my understanding most of the larger labs retain B&W processing machines as they are required extensively for developing optical soundtrack negatives.

Sorry, NEGATIVES you said.

As far as I know, the sound negative is also made on a special type of colour stock, specifically to avoid the need for B&W processing.

[Russell Richard Fowler]

The main problem of splicing color print inserts into B&W print film is possible focus shift during projection....with an automated projection system it is a hassle. Silver in B&W prints tend to heat up in the projector gate compared to dyes in color print film.

[John Sprung]

Prints get spliced a lot. Every time a projectionist builds up a show on a platter, they cut the leaders off and splice all the reels together. Then they break them back down again for shipping to the next theater. So, I doubt that anybody would be all that worried about splices.

 

 

 

 

-- J.S.

[K Borowski]

Focus *can* jump when a splice goes through the gate, especially a less-than-perfect one. This is, of course on projectors without focus locks.

 

Then, of course, if there is a film that runs emulsion out (something on reversal film) or a change in the base from acetate to estar the focus would shift.

 

So if "Schindler" used, for instance B&W acetate stock and color estar, there would be a change in focus necessary.

[Russell Richard Fowler]

Acetate B&W to Acetate color can focus drift.....

[David Mullen ASC]

Back then it was common to splice acetate b&w prints with a few color shots (I assume on color acetate print stock) so that you didn't have to print the whole movie on color print stock if there were only a couple of color shots. "Zelig" did this, "Rumblefish" did this, "Schindler's List" did this.

 

There is even one shot in Kurosawa's b&w "High & Low" where there is a pink cloud of smoke seen on the horizon -- original b&w prints actually hand-tinted the column of smoke pink, but later prints spliced in a color print for this shot. Unfortunately, decades later, this shot has ironically red-shifted so rather than a pink column of smoke in a b&w landscape, the whole shot is pink.

 

Anyway, it's silly to say that Spielberg didn't know how to splice Estar when there was no Estar b&w print stock back then.

 

The problems with the splices coming apart and the b&w print warping (due to the higher IR absorption) compared to the color shots caused later prints of "Schindler's List" to be entirely printed on color stock.

[Russell Richard Fowler]

Most locations there is no one watching the screen to "tweak" between film stocks.....or listening to a projector gate "asking you" to check focus.

[Henri Titchen]

Sorry, NEGATIVES you said.

As far as I know, the sound negative is also made on a special type of colour stock, specifically to avoid the need for B&W processing.

 

The only Kodak sound negative films I have heard of are 2374 and 2378:

http://motion.kodak.com/AU/en/motion/Produ...uction/2374.htm

http://motion.kodak.com/AU/en/motion/Produ...uction/2378.htm

 

These are both B&W process. Using D-97 developer. This means the lab processing sound negs needs to retain a B&W developing machine.

 

H.

[K Borowski]

Acetate B&W to Acetate color can focus drift.....

 

So can acetate color to acetate color or estar color to estar color.

 

 

I'm not trying to get in a contest with you to see who can piss the farthest. . . :blink:

 

 

 

If B&W soundtrack stock uses the same developer as regular B&W neg stocks, which surprises me, the processors should be almost completely interchangeable.

 

I'm not up on soundtracks, really. I would have thought that they'd use a high-contrast developer, not D-97.

[Stephen Williams]

Hi,

 

In the 1980's I often used GEV 553 HI CON for film optical work, mattes & titles, it's original use was sound tracks. It went through the normal B & W bath.

 

Stephen

 

So can acetate color to acetate color or estar color to estar color.

 

 

I'm not trying to get in a contest with you to see who can piss the farthest. . . :blink:

 

 

 

If B&W soundtrack stock uses the same developer as regular B&W neg stocks, which surprises me, the processors should be almost completely interchangeable.

 

I'm not up on soundtracks, really. I would have thought that they'd use a high-contrast developer, not D-97.

[Russell Richard Fowler]

Basically there will be some ( in some cases minute ) focus drift based on location of image on the emulsion, composition of emulsion, thickness of base, F speed of reflector and lens, depth of focus on lens, type of film trap in projector.

 

I was in Latin America when "Schindler's List" came out and saw the problems with the cut in of color stock into black and white and the later run on color stock. Lack of on hand projectionists due to automation makes it more of an issue today than in the past. Cutting in clips of I.B. Technicolor into B&W print stock was not a big issue since it behaved like B&W stock in the projector gate...but that is another bye gone option.

 

Another nail in the B&W coffin is that many customers and labs may deal with a company like N.T. Audio to make their soundtrack negatives and not have to deal with the processing.

 

After four months of Radiation therapy last year.....my piss range is excellent.....

[Dirk DeJonghe]

Sound negative stocks (both Kodak and Agfa) are processed in normal positive developer (higher contrast than negative developer). They can be run together with normal B&W positives but may need special processing times to achieve the aim density/gamma;

 

Are processed in B&W negative developer: normal camera negatives, intermediate negative (5234), interpositive (5366).

We run a combination processing machine with dual developer tanks, one for negative, one for positive, all the other steps are common. For similar size, B&W machines are much slower than color machines due to the much longer washing times and lower temperatures. If you would fill a color machine with B&W chemicals, it would be very inefficient, the machine would have to be slowed down to achieve the required washing times. Also B&W is a low temperature process at 21°C and you would need cooling to counteract the heating of the pumps. We used parts from an older color machine to build this B&W machine but an extra water chiller was needed with heat exchangers on the three main solutions.

 

Also a good sensitometer and knowledge to use it is required in order to do proper B&W.

[John Sprung]

The other thing about B&W sound negatives as opposed to picture is that the replenish rates and silver recovery are very different, because a very much smaller amount of the film is exposed on the track, and much more silver is recovered.

 

 

 

 

 

-- J.S.

[K Borowski]

After four months of Radiation therapy last year.....my piss range is excellent.....

 

Your personal situation aside, you DO want a pissing match?

 

 

Sorry, I am not going to play.

 

Splices throw every reel of print film out of focus if there isn't a focus lock on the projector. I don't care if it's IB tech, acetate, estar, Eastman, Kodak, Fuji, Agfa, whatever.

 

But the average movie has over two dozen splices in it, from head to tail.

 

Sounds like you don't know what you are talking about. If you want to see perfect focus go to some of the very very few reel-to-reel changeover houses out there. Having worked in one, once, they do NOT take extra special care of focus throughout each reel. They stand around, waiting for the change-over cues, looking at their cell phones or laptops the rest of the time.

 

So, sorry you'd still be F-ed if you wanted to see sharp focus, perfectly, on a reel with splices there too.

 

 

 

I'm done with this thread; too many idiots here. . .

[Paul Bruening]

Sorry, I am not going to play.

 

I'm done with this thread; too many idiots here. . .

[Paul Bruening]

Of course, who can sustain a resolution of 256K in the current digital and computer environment?

 

For kicks, I did some math on that. I took an image I had on file. It was 4,000 x 3,000 in .tiff format. It weighed in at 34.4 MB. When I jumped it up to 256,000 x 192,000 pixels it weighed in at 137.3 GB. If a whole movie was made with 256K res in a 2 hour length using that image statistic: 173,000 frames x 137.3 Gb = 23,752,900 GB. or 2,375.29 TB. just for the storage of initial scans. That doesn't account for any work files. If it was a CGI heavily involved movie, it could easily multiply the storage requirements by 10 or even 20 = 23,752.9 to 47,505.8 TB.

 

That's a whole bunch of 5.25 inch floppies.

[Phil Rhodes]

Although actually, with current clustered storage technique, not impossible. Just expensive.

 

P

[Paul Bruening]

Although actually, with current clustered storage technique, not impossible. Just expensive.

 

P

 

I agree, Phil. Even using the render farm formula I'm going by, a 2,375 TB sized movie with no significant FX could get by with about 3X storage or 7,125 TB total production storage (1X for scans, 1X for minor CG and trial renders and 1X for final renders for film-out). With 12 TB SATA 3.0 possible on a moderately priced 64 bit quad core mobo that comes out to 594 mobos with 6 X 2 TB SATAs per with a total of 3,563, 2 TB drives. 594 mobos at around $800 per rig comes out to $475,200. 3,563, 2 TB SATAs at $120 per comes out to $427,560. Add in all the networking, cables, KVMs, racks at around $150,000... (we'll worry about the power feed, AC and electric bill later). You could cut the number of mobos by putting 4X SATA port cards in fewer mobos. But, my thinking is that all those mobos are going to be needed to do these whopping render tasks, anyway.

 

$1,052,760 to grind out a "fully as good as film negative" DI.

 

Now, to solve the scan and record at 256K challenge.

[Phil Rhodes]

I think you've got to budget for quite a bit of software engineering to make it in any way usable.

 

What're you going to display it on?

 

In any case, I don't think it's too much of a leap to say that these insane figures are far from necessary - four appears to be adequate, six or eight very much so, and anywhere beyond ten is imax-plus insanity land.

 

Not to say that these techniques don't have their application, though.

 

P

[K Borowski]

Once again, you've left out the most important cost in any film effort. . . human labor costs.

[Phil Rhodes]

I think we're just talking about post hardware here.

 

Of course, actually doing this would involve weeks of labour in setting up.

 

P

[Keith Walters]

Your personal situation aside, you DO want a pissing match?

So, sorry you'd still be F-ed if you wanted to see sharp focus, perfectly, on a reel with splices there too.

You'd think considering that sub-$100 still cameras are available with quite effective auto-focus lenses, somebody could make something similar for cinema projectors.

 

All that would be required is a video camera zoomed in on the centre of the screen controlling a servo motor attached to the projector lens. Considering that the projector normally doesn't change its distance from the screen, and there is only one focal plane to worry about, only small adjustments should ever be needed.

[K Borowski]

You'd think considering that sub-$100 still cameras are available with quite effective auto-focus lenses, somebody could make something similar for cinema projectors.

 

All that would be required is a video camera zoomed in on the centre of the screen controlling a servo motor attached to the projector lens. Considering that the projector normally doesn't change its distance from the screen, and there is only one focal plane to worry about, only small adjustments should ever be needed.

 

I want to say that some 35mm projectors have focusing *locks* or at the very least lens barrels that are resistant to being accidentally turned.

 

 

I seem to remember seeing a focus lock on *something* somewhere.

 

 

 

The focus did drift on several of the different projectors I worked with. And you're right, you'd think there'd be auto-focus available too. I know they had it on slide projectors back in the day.

[John Sprung]

Yes, you definitely do have to focus projectors. Temperature changes, vibration, different prints.... Binoculars help a lot.

 

 

 

 

-- J.S.