Hello APUG from FILM Ferrania

[Photo Engineer]

CMACD, NZOOMED, there is a lot missed here. Suffice it to say that you do not know a lot about high speed multi layer coating. Not your fault, but you do not want defects spread out, and the rollers and cabinets are oversized to allow undercut rollers to hold the film stiff and prevent surface defects and so there is a 2" minimum undercut (40" + 2") to prevent touching.

Lots of engineering here that slips by. I could teach a year long course in this and still be way short as I am not the person to teach this sort of course. I was not a coating engineer.

PE

 

[TheToadMen]

You mean like this?

I would love to see Ken feature in this short film wearing an APUG shirt

Bert from Holland
http://thetoadmen.blogspot.nl

 

[railwayman3]

Ken, you almost brought a tear to my eye. One of the best posts I've read in 17 years of internet discussions.

It just needed a romantic ending, where they walked arm-in-arm into the sunset.

Great post though, seriously.

 

[Theo Sulphate]

You mean like this?

Yeah - exactly like that. This could really be done. Have it on the Ferrania and APUG websites, plus YouTube at the least.

 

[Nzoomed]

CMACD, NZOOMED, there is a lot missed here. Suffice it to say that you do not know a lot about high speed multi layer coating. Not your fault, but you do not want defects spread out, and the rollers and cabinets are oversized to allow undercut rollers to hold the film stiff and prevent surface defects and so there is a 2" minimum undercut (40" + 2") to prevent touching.

Lots of engineering here that slips by. I could teach a year long course in this and still be way short as I am not the person to teach this sort of course. I was not a coating engineer.

PE

Yes i dont know very much i admit.
I still dont know how all the rollers dont disturb the coating before it sets, but i think i read about it going through an air cushion where there is no physical contact, but i cant see how that works.

 

[Ricardo Miranda]

You'll need to visit the Ilford factory to see one working.

[video=youtube_share;vtz7a_Guu54]http://youtu.be/vtz7a_Guu54[/video]

 

[Photo Engineer]

Undercut rollers are shaped like thisi: [-] with a depressed center and raised edges. The uncoated edges ride on the raised edges of the roller and the coated center does not contact anything. An air bearing is simply a plate with holes in it and air blowing out through the holes. This air pressure keeps the film from contacting the plate. If the plate and film are at the right angle to the initial direction of travel, then the direction can be changed in any way from 45 - 90 - 180 degrees.

In no case does the coated film surface touch anything.

PE

 

[Nzoomed]

Undercut rollers are shaped like thisi: [-] with a depressed center and raised edges. The uncoated edges ride on the raised edges of the roller and the coated center does not contact anything. An air bearing is simply a plate with holes in it and air blowing out through the holes. This air pressure keeps the film from contacting the plate. If the plate and film are at the right angle to the initial direction of travel, then the direction can be changed in any way from 45 - 90 - 180 degrees.

In no case does the coated film surface touch anything.

PE

OK, that makes perfect sense, from various photos ive seen, they looked like normal rollers to me, thats all.

 

[Truzi]

I'm imagining the air-bearing as being similar to an air hockey table. Does that analogy work?

 

[Black Dog]

Ken, you almost brought a tear to my eye. One of the best posts I've read in 17 years of internet discussions.

Well done Ken

 

[Photo Engineer]

Exactly the same as the air hockey table.

 

[Sirius Glass]

Why age film? I age on my own and if left alone I am sure that I could be come ripe.

 

[Nzoomed]

Well i guess we will know what its like with the first shipment of Ferrania film, i cant wait to shoot mine!
If it appears too "fresh" i guess we can experiment by leaving film out of the fridge.

But as far as im concerned, i wouldn't have thought that ageing film would be necessary.
I would have thought that with all the R&D in developing an emulsion they would have been testing the film straight away to see what results they get, obviously they would test the film for its shelf life, but i doubt a film would have been intentionally designed to improve with age, unless this was a way to extend its shelf life and allow for poor storage during transit etc; or perhaps this is the nature of film chemistry that has to be taken into account.

Either way, Photo Engineer should be able to answer this.

 

[Chris Livsey]

http://www.kodak.com/global/en/professional/support/techPubs/e6/e6.pdf

"To provide films that meet the needs of different kinds ofphotographers, Kodak allows for this aging process duringmanufacture. Kodak builds a small manufacturing bias intofilms for general picture-taking to compensate for changesproduced by typical storage conditions and delays betweenpurchase and processing."
"Kodak professional films are close to optimum colorbalance when they are manufactured and packaged. The filmwill remain near this balance if it’s stored as recommendedin the instructions or on the film carton and processed beforethe expiration date on the carton."

 

[Sirius Glass]

http://www.kodak.com/global/en/professional/support/techPubs/e6/e6.pdf

"To provide films that meet the needs of different kinds ofphotographers, Kodak allows for this aging process duringmanufacture. Kodak builds a small manufacturing bias intofilms for general picture-taking to compensate for changesproduced by typical storage conditions and delays betweenpurchase and processing."
"Kodak professional films are close to optimum colorbalance when they are manufactured and packaged. The filmwill remain near this balance if it’s stored as recommendedin the instructions or on the film carton and processed beforethe expiration date on the carton."

My freezer and my refrigderator handle that part of the film aging, not my aging.

 

[Chris Livsey]

My freezer and my refrigderator handle that part of the film aging, not my aging.

I'd just be happy that I didn't have an expiry date on my carton

 

[Photo Engineer]

In my experience, Agfa color films did not keep well even when frozen.

PE

 

[Nzoomed]

In my experience, Agfa color films did not keep well even when frozen.

PE

Interesting to learn about that, i always understood that the organic chemistry in film would keep almost indefinitely when frozen, as it keeps the molecular bonds virtually 100% stable, i know that background radiation can affect film over time though, even when frozen.

 

[Photo Engineer]

Oxidation, pH change, reaction between ingredients, interlayer exchange........... Geez the list goes on! It depends on the job done by the Photo Engineer that keeps things stable even in a freezer.

This is why I hate to get into these discussions.

PE

 

[Sirius Glass]

This is why I hate to get into these discussions.

PE

Wait, now they will want to make Kodachrome in a cesspool.

 

[FILM Ferrania]

IMeanwhile.....I would like to see what Dave Bias from Ferrania has to say about this.

Apologies, but this is not a question I can answer.

I'll ask the team in Italy about aging at my next opportunity.

But I would guess that, once we are in normal production, we are likely to follow a similar "Mondavi Rule.".

 

[Nzoomed]

Oxidation, pH change, reaction between ingredients, interlayer exchange........... Geez the list goes on! It depends on the job done by the Photo Engineer that keeps things stable even in a freezer.

This is why I hate to get into these discussions.

PE

I guess we can give you credit for making Kodak's films store well in our freezers!

 

[Photo Engineer]

My freezer is set far below normal household levels. Agfacolor neg. went fast!

PE

 

[RattyMouse]

Wrong thread! Sorry.

 

[Roger Cole]

My freezer is set far below normal household levels. Agfacolor neg. went fast!

PE

Two observations:

1. There was a very long, contentious thread about whether freezing film actually helped preserve it. PE freezes his film. 'Nuff said.
2. I have some Optima 400 from the 90s, supposedly frozen since purchase when I bought it off eBay but of course I've no way to verify that, and definitely frozen by me since. It seems ok. A bit warm but so was the light.