The facts of film production

[David Nardi]

Looks like we'll have to learn to be chemists again if we want to keep shooting film.

Just think of the perks; you can create an emulsion that suits you the best!

 

[David A. Goldfarb]

Ed;

In the words of Desi Arnaz, "'splain". Your equation uses 42/80? I guess I don't follow. Anyhow, the coated web is 40" due to the waste of 1" at each side of the web. But I get 5000 * 12 /60 = number of 20 exposure roll lengths x ~40 = number of 35mm rolls (it assumes 1" for a 35mm roll, but this is too narrow). This is about 40,000 rolls so we are close.

I think Ed's assuming 36 exp. rolls, so 80 square inches per roll (aside from not accounting for the waste at the edges of the roll, which you've already mentioned).

 

[nickandre]

5000 * 12 * 42/80 = 31,500 rolls. So, yeah, 1000 is "crazily off."

Ed

I'm sorry if I assumed since KC was ONLY sold in 35mm they coated in the 35mm width. Would someone care to calculate over that entire roll how many 4x5 sheets they lose to the punched out sprocket holes?

Lets see...if I shoot 3 rolls in a year...

 

[CRhymer]

Making 4x5 Kodachrome from "hanging chads"

Tiberius,
I suggest you read some of the past threads, which tell a lot about how this all works - to a point. This is a lot more complicated than you imagine. I made the same mistake. Firstly, think about the order of making the emulsion, coating and finishing and slitting and perfing. Also 35 mm film is coated on a different thickness and type of base than sheet film. Just because the math may work doesn't mean the process works. If Dwayne's are still doing the volume you state, then that is good news in a way, since it has not dropped off from the amount suggested 18 months ago. One of the reasons Kodachrome went south is that E-6 got very good. My Kodachrome movie films from the 50's are as good as new. My family's slides from the 70-80's are a Photoshop challenge. But, non-Kodachrome transparencies improved and became more or less as archival.

Now, there is a huge basket of E-6 film products available at present. Don't be fooled. The E-6 labs are falling like ten pins. Movie film is keeping the industry alive. So, if Kodak raises the Elmer the Kodachrome Elephant flag once a year to signal one day's coating, or whether they can cut all they need from existing stock is probably immaterial. (Consider how long Techpan was being sold after the last coating).

I really don't know a lot about this, but understanding the photographic film/paper making business will bring you to your knees.

Cheers,
Clarence

Hope you find some K-25, it is a wonderful historical experience.

 

[phenix]

PE,

There are some years already I read your posts (not all, just some), and I show you the greatest respect for the scientific knowledge and experience you have and share here. But today you give me so much pain when you sustained that film is like vinyls, a simple recording support. This is only the technical aspect, completely ignoring the relationship that an artist or a hobbyist establishes with the material he is working with and on. This material is his partner, not a cold peace of technique. When I’m in the darkroom I feel like a magician, while in front of the computer trying to do something creative I feel like a hacker – I somehow exaggerate, but the difference is there. What you said is far from the film user’s true, and it is painful to learn that Kodak people think like that – I suppose you did not speak only from yourself, but there’s a professional and an organizational culture behind your words.

Beside that, the rest of what you say does not contradict what I said, even if you think it does. PE, can you think production other than you lived it when at Kodak? I think you cannot. Today, there are so many things that have to change, that’s impossible for me to even think to dress here an exhaustive list. Instead, I can highlight a few:
- the coating line you are talking about is for mass production of film and cannot face the new client’s needs,
- the "co." status is not appropriate because of shareholders control, while a "ltd." or "inc." form would be far better,
- the 35mm film doesn’t necessary has to come in cassettes, we can roll it from bulk too, and this at a lower price, so we can buy and shoot more.
Not only several aspects have to be rethought (reengineered if you like), but everything, the whole business! What lakes is vision, or to be more precise, a list of goals to be challenged by (or to challenge) people like you.

You also said I have to look only at the big 3, because others are using old technologies? If a temporary step back can save the film, and give hope for new steps forward to come soon (and why not in other directions than what are the today’s modern technologies), than why not? Progress is not always linear. So many times, to meet the change, a step back is benefic. And besides that, there’s no sacrifice – on the contrary: I’m ready to experience technologies I couldn’t, because I was too young (‘60s) or even not born yet (‘30s). Like Wolfeye previously said, let’s have fun.

PE, fine art painting did not die when photography came in. On the contrary, it emancipates herself from figurative and evolved! Nor did B/W die when color came in. Now, if B/W film won’t be buried by elitist nostalgia associated with lake of vision, it will survive and soon evolve in forms I can not even imagine today.

 

[AgX]

dear zeus-that could last until the end of time

A late Agfa coating machine (now said to be bought by Inoviscoat) had in the Agfa setup a capacity of

850 Million type 135 per year...

 

[AgX]

Now, the bottom line is this, the machine must be threaded with leader before starting (5000 ft) and threaded with leader after coating (5000 ft), so if we assume 1 roll, it uses 3 master rolls to set up the machine and shut it down. Pretty expensive, no?

PE,

I don't understand why one would use about a whole roll length (5000 ft) of leader.

Just use enough for the machine lenght.
Just..., well for that Machine above that would have been about 700meters. Add length for getting the machine on speed (130m/min). Double this all if necceassary for a use of a second leader at the end of coating. But this all would be blank leader and reusable. Wouldn't it?

However, one would have to add coating lenght from starting coating until an acceptable result is yielded as waste. I got not the slightest idea how much that would be.


Btw, the above machine could handle master rolls of 4000meters...

 

[Stephen Frizza]

"So, we have discovered that it takes 3 years or more to sell something that used to move in 1 year, and which goes bad in 2 years.

What do we do?"


Why not mark the price up and up and up....its film!!! who cares of cost. here is australia its ludicrously expensive anyway. If a quarter of the roll goes off make the product 25 percent more expensive? is half of it goes off make it 50 percent more expensive....

 

[AgX]

But phenix does not want to pay more than 2$.
And I am only buying long rolls to get the single roll price down.

Consumers are quite different thus.

 

[Film Enthusiast]

A late Agfa coating machine (now said to be bought by Inoviscoat) had in the Agfa setup a capacity of

850 Million type 135 per year...

Dear AgX,

AFAIK is was the maximum capacity of the Agfa K14 film coating machine. For paper they used their L6 machine.
The machine bought by Inoviscoat is not the whole, gigantic machine, but the essential parts. The machine is scaled down to smaller and more economical production capacity.

Regards,
Michael

 

[AgX]

Yes, I read that too.
Scaling down probably means shortening the chilling and the drying section whilst running the machinery on lower speed.
Or one could decrease the width of the coating cascade.

 

[Film Enthusiast]

Or one could decrease the width of the coating cascade.

AFAIK they have done that.

Regards,
Michael

 

[Photo Engineer]

Well, AFAIK, the total track length of a Kodak 42" machine is about 5000 feet due to the high coating speed and the drying demands placed on the system by this speed. That is why almost a full master roll is used as leader. This was told to me by the manager of paper coating, I did not go into the machine and measure it personally.

There is also startup and shutdown to consider which is about 10% of the start and 10% of the end of any run due to run up to coating speed. You cannot just start at coating speed, or you rip the film or paper into shreds. (with estar you acutally damage the machine rather than tear the estar) I have actually seen paper tearoffs when they went to "speed".

There is also about 10% defect or less in any master roll which must be cut out. This is done by IR scanning and mapping software to calculate the best 'cut' of film for a roll.

In recent years, Kodachrome was coated every November and supplied the world with one run. Last year, sales were so low that the run was delayed a few months, so we will see about this year.

Shims are commonly used on the slide or curtain coater (< note that I use Kodak terms, not Agfa terms - since the original patents for this were held by Kodak, I stick to them) to narrow the width, but turbulance can often disturb the edges, as the flow comes in from the wider hopper and give you wide messy edges, but it is done. Kodak also has (had) a 21" coating machine and an 11" coating machine that can do production, and they also have (had) several 4" coating machines. Then again, there are wider machines as well, such as the 72" machine in Colorado.

Remember to subtract 2" from all Kodak machine widths due to edge defects and due to rollers which support the film or paper during drying.

If you slow the machine down, then several problems arise. The air pressure in the drying cabinets must be adjusted to prevent the film from "floating" improperly on the air bearings. So, machines cannot just be sped up or slowed down. If you do, you can overdry leading to static charges and discharges on the film as well as keeping problems. The film must be at a given precalculated value of temperature and humidity as it rolls up onto the final master roll or it will not keep properly.

I hope that this answers several people at one time.

PE

 

[David A. Goldfarb]

Out of curiosity, can the leader and trailer be reused for those purposes, or can they be made out of some less expensive material than the film or paper to be coated, or do they use fresh leaders and trailers of the same material as the coating substrate each time?

 

[Neanderman]

I think Ed's assuming 36 exp. rolls, so 80 square inches per roll (aside from not accounting for the waste at the edges of the roll, which you've already mentioned).

That is precisely my assumption.

Ed

 

[PhotoJim]

Why not mark the price up and up and up....its film!!! who cares of cost. here is australia its ludicrously expensive anyway. If a quarter of the roll goes off make the product 25 percent more expensive? is half of it goes off make it 50 percent more expensive....

You'd have to mark it up more than that.

If a quarter of the roll goes off, you'd have to mark the product up 33 1/3%.

If half the roll goes off you'd have to mark up the product 50%.

To illustrate why, imagine 90% of the product goes bad. Your instinct would be to add 90% to the price. However, you have only gotten one-tenth (10%) as much film as you have waste (90%). This means you have to multiply the price by 1000%, or ten times, to recover that expenditure.

This is because percentages are ratios, not simple additions and subtractions. 50% off a product that is priced at $100 is $50, but you'd have to increase that $50 price by 100% to get back to $100.

 

[Photo Engineer]

Out of curiosity, can the leader and trailer be reused for those purposes, or can they be made out of some less expensive material than the film or paper to be coated, or do they use fresh leaders and trailers of the same material as the coating substrate each time?

Yes, the leader and trailer are reused as long as is physically possible. The time is shorter for paper though. And, the entire roll must be inspected for integrity before reuse.

PE

 

[Neanderman]

In recent years, Kodachrome was coated every November and supplied the world with one run. Last year, sales were so low that the run was delayed a few months, so we will see about this year.

Amazing... I assume the same coating machine is used for other films as well? Do you have any idea how many days a year, in total, are spent coating all films?

Kodak also has (had) a 21" coating machine and an 11" coating machine that can do production, and they also have (had) several 4" coating machines. Then again, there are wider machines as well, such as the 72" machine in Colorado.

Have these all now been discarded? I know they moved (all?) production to a new coating building recently, presumably one scaled down from the old building/buildings.

If you slow the machine down, then several problems arise. The air pressure in the drying cabinets must be adjusted to prevent the film from "floating" improperly on the air bearings.

I would expect this would have an effect as well on coating itself on a curtain coating machine.

 

[AgX]

On your last qestion Neanderman:

Employing a through coater the layer thickness is depend on emulsion viscosity as well as on base speed. Thus you have a viscosity/speed couple. If one wants to speed up for example and yield the same result with the same emulsion you could use an air knife to control thickness.

On a curtain coating system one should have more flexibility by cntrolling the flux of the emulsion (by the pressure inside the coating head) I assume.

But most probably in practice this all would be even more complicated.

 

[Stephen Frizza]

my point earlier was as demand decreases and percentages of films go off why not just make those who lone it pay more and more and more?
hehehehee... we love film right we would pay it?

 

[bdial]

we love film right we would pay it?

I love film too, but when the price approaches infinity, the love might diminish. A lot might depend on what the payoff time is for a digi back of whatever size.

Presumably by then, PE will have his book and DVD available and our problem might be the availability of Silver Nitrate and photo grade gelatin. I fear that in time, the sheet back I bought for my Hasselblad will become very useful.

For now, I'm going to buy as much film as I can get my hands on, and reasonably store.

 

[CRhymer]

Anecdotal evidence - Kodachrome

At $10.00 a roll in hand plus $13.00 for processing (total cost including tax of $ 23.00CDN) door to door, I shoot and probably will shoot about 6 rolls a year. At $16.00 a roll tax in for film (what I pay to support my local store) I will shoot less. At $25.00 a roll of film I will probably shoot one roll or none per year.

There have been complaints about Dwayne's (I have none). But if the processing gets poor or is perceived to be poor fewer people will use it. If I have to pay for shipping or increased processing costs I will buy no more.

I should add, Kodachrome's colour is unique, but not everyone's favorite, nor mine. Also, stockpiling it is futile if there is no one to process it. Yes, I know it can be done. I doubt very much that anyone is going to start doing this in any volume and with good quality control should Dwayne's shut down.

Cheers,
Clarence

 

[Photo Engineer]

Well, again answers to several questions at one time.

At one time, Kodak had a paper coating building with 6 machines of which 4 were operational at one time while 2 underwent maintenance. They had several film machines in another building. There were also sites in France, England, Rochester, Colorado, Canada and Australia. All of these ran at full speed 24/7/365. Today, they have basically a plant in England, Rochester and Colorado (site now rented from Onyx). These machines run about 16/5/200. Every machine can produce any product and a complex schedule is set up to accomodate the various products.

As to what has been discarded or kept, IDK. If I did know, I probably would not tell.

Viscosity, coating speed and drying contidtions are interrelated. As viscosity goes down, water content goes up and vice versa, but viscosity is also controlled by incorporated chemistry and so a tight control must be kept to prevent problems in the coating operation.

Layer thickness is most critical with Kodachrome from what I understand.

PE