How long can we keep Provia400F? (RE bulk roll order)

[zhoufang]

So that at least there is no visible difference in pic quality?

The offical storage life by of pro slide is about 6 mths.

I was told that by keeping pro slides frozen (at -20c instead of 15c) help quite a bit, but still cannot keep them for very much longer (ie n years without degrading) as there is the limiting factor of high energy outerspace radiation that "expose" the film as time goes by and low temp doesn't help.
(there was discussing in NGs about how long can film be kept in liquid nitrogen or absolute zero temp, conclusion was not much longer than -20C)

If we can keep the film longer than I believe many ppl will order/order more bulk rolls.
I don't mind order 1-2 rolls if they can be kept for 5 years.

To protect the film from outerspace radiation (ie: alpha, beta, garmma), we need to use dense mass blocks to cut them out.
Anyone know where to get massive lead blocks?
Lead can keep uranium safe for ppl to carry, if I remember correctly just a few cm of lead can cut down these high energy radiation by a factor of 10. double the thickness means a factor of 100.

May be we can keep our bulk rolls in some of the core member's home, there we can keep them safe for n years where n>5. There must be someone having empty freezor space. Anyone sells ice cream here?

[YSLee]

When you've actually shot with bulk roll film that's past it's expiry date and the colours are way off, come back to us.

[ckiang]

Borrow an EOS 1V, load the film in, go to your favourite photo location, set to continuous mode, press and hold. Repeat 20 times. 1 can will be finished in 80s.

Regards
CK

[Jed]

[zhapchit]

hmm...

[Shadus]

......
(I'm struck wordless... dunno wat to say)

[Ian]

I do hope you're kidding with this crap right?

Quote: Originally posted by zhoufang So that at least there is no visible difference in pic quality? The offical storage life by of pro slide is about 6 mths. I was told that by keeping pro slides frozen (at -20c instead of 15c) help quite a bit, but still cannot keep them for very much longer (ie n years without degrading) as there is the limiting factor of high energy outerspace radiation that "expose" the film as time goes by and low temp doesn't help. (there was discussing in NGs about how long can film be kept in liquid nitrogen or absolute zero temp, conclusion was not much longer than -20C)

According to Kodak Professional Services slide emulsion for professionals when stored refrigerated has a guaranteed life with no perceptable colour shift of 12 months.

Most professionals prefer to buy in enough for a 3-4 month period.

Quote: Originally posted by zhoufang If we can keep the film longer than I believe many ppl will order/order more bulk rolls. I don't mind order 1-2 rolls if they can be kept for 5 years.

If your going to be shooting that little, you'd be better off to buy a pro pack or two each year rather than bulk rolls.

Quote: Originally posted by zhoufang To protect the film from outerspace radiation (ie: alpha, beta, garmma), we need to use dense mass blocks to cut them out. Anyone know where to get massive lead blocks? Lead can keep uranium safe for ppl to carry, if I remember correctly just a few cm of lead can cut down these high energy radiation by a factor of 10. double the thickness means a factor of 100.

Who told you this load of crap? Ever heard of the Van Allen Belt?

Film has been found and processed that was shot over 50 years ago (reference film found on dead mountaineers etc) and that film was NOT fogged. The levels of radiation (gamma, alpha and delta) that reach earth is so low that some estimates rate regular 100 ISO film exposure to a nominal fog base of some hundreds of years if exposed to earth bound natural radiation.

[zhoufang]

Quote: Originally posted by Ian Film has been found and processed that was shot over 50 years ago (reference film found on dead mountaineers etc) and that film was NOT fogged. The levels of radiation (gamma, alpha and delta) that reach earth is so low that some estimates rate regular 100 ISO film exposure to a nominal fog base of some hundreds of years if exposed to earth bound natural radiation.

Do u mean in the freezer I can keep the film for tens of years without fogging or colour shift?

[ckiang]

Quote: Originally posted by zhoufang Do u mean in the freezer I can keep the film for tens of years without fogging or colour shift?

The point is, why would you want Buy so much film that you can't finish that you need to keep 10 years....

Regards
CK

[Shadus]

...
(I'm still wordless)

[Kei]

[Richard]

Quote: Originally posted by Shadus ... (I'm still wordless)

You sure speak a lot for someone who's wordless. *G*

[Shadus]

(/me wondering why am picked upon )

Actually, there's something we all need to know.

IMPT note to everyone using professional films
-------------------------------------------------------------

1. Never bring film to hospital in general, there's a lot of radiation leakage in hospital. These are likely to cause accidental exposure and color shift

2. Always ask for hand check in airport. Those film-safe scanners are still too much for professional level films

3. Always keep film in the film canister provided. These canister contains slight amount of lead which blocks radiation present in our environment

4. Ever wonder why nuclear plants allows film-based cameras but not digital ones? Coz your film will get exposed in a nuclear plant!

5. Never put your handphone close to your professional films. These modern day equipment have radiation high enough to cause color shifts in the film