Thnaks DK, now this is more like it should be. Anybody interested in reading about the stability of pigments and dyes should read the article. Very informative and much more complete than the Wilhelm tests. The only objections I had was the humidity chosen, and of course the lack of projection to their results.
a constant 50% RH can only be found in very few places, I live in a semi desertic zone and I know the RH in my house is in between 60 and 70%. Places like Arizona, Utha, or New Mexico might have at given times a 50% humidity but rarely is it constant.
OTOH I was glad to see that someone finally addressed the problem of pollutants and the effect of free radicals.
I would have liked to see how they plan on making projection predictions out of the data they obtained.
Most gratifying is the fact that their data conforms to the anecdotal data reported by people, ei, dyes fade faster than pigments, pigments also fade albeit at a slower rate, environmental pollutants have a significant effect on fading and color reproduction, specially in the "neutral" tones is rarely neutral thus affecting the color response and fading qualities.
Very good paper DK, thanks again.
True--but the group that paper was probably intended for were conservators in archives...the standards that are used almost universally are for ranges that are 30-50% rh, and less than 70 degrees F. The ranges are around 2-5% above or below for RH and same for temp. We have an HVAC system in our building that's like this for the exhibit galleries and storage areas. It basically heats & cools at the same time. The conservators track it daily on hydrothermograph dataloggers posted around the facility.
Originally Posted by Jorge
Typical recommendations might be--let's see:
b&w--medium term: 20-50% rh/77 degrees F max.
longterm: 20-30% rh/ 70 deg. max.
or 20-50%/ 50 degrees max.
color---medium term: 20-50%/77 degrees max.
longterm: 20-30%/ 35 degrees F max.
or 20-50%/ 15 degrees F max.
35-59 degreesF/30-40% rh.
35 or less degrees F/ 30-50% rh.
I have a datalogger next to me, and it reads 71 degrees F and 45% RH today. We put indicators in some of the file cabinet drawers as well--and I just looked at one and it reads 70 and 40% rh. If the room outside cycles around, it takes a couple of days to actually get into the drawers if they stay closed...this is just for my office basically-and the little room we use to file our working negs and chromes in...
The big danger is humidity--if it gets above 65%, then mold spores can become a problem. The tradeoff, then, is to control the humidity in a way where the temps don't get too high--for color, the temp is the aging factor in with the light damage. For b&w, humidity is more a factor.
On that same pollution control site, there's a paper somewhere dealing with the realistic issues of maintaining those standards around the world. Someplace like Anchorage, Alaska was one of the only "natural" environments....but archives & museums would be trying to keep the RH down under 50 and under 70 degrees year round--just out in open areas. In storage areas, the temps & rh might be much less. There are some areas of our building that are downright frigid...
Here's a site the IPI runs for preservation. If you download the "Preservation Calculator", you can get an idea of how they extrapolate data for designing film & print storage areas mainly, but it could be used for other organic materials....this is also offered in conjunction with with their guide to acetate based film storage--you can buy it from Light Impressions, Univ Products etc or you can get it as pdf file for free from their site. They have some similar (not free) publications for color materials.
There's more of this out there--it's mostly on sites aimed at archives and museum profession.
BTW--supposedly the ANSI/ISO photo materials group has split into sub-groups to try to come up with a test for inkjets and other computer output materials....
my opinions only.
I understand the paper is directed mostly to museums etc, but even then wouldn`t it make sense to make similar test for "comercial" products destined to be used in a less controlled environment?
So far this is the first paper I have seen that addresses the pollution issue. I think if the test had included the same test with a higher RH the results would have been much worse. After all, water is a wonderful medium for chemical reactions...
In any case I think Wilhelm and RIT have something to learn from this people.
yeah--but one problem would be figuring out what that environment would be, since it would be something different all over the world. I read some posts on this conservation list some folks are on where I work--the ANSI/ISO group was splitting up into sub-groups to study the variables of deterioration in inkjets-. Apparently the standards group had to first come up with a standard test--that could be applied evenly around the world--and they acknowledged all sorts of problems with this.
I haven't followed this much lately....in some ways, I'm resigned to it and don't care 100% since I don't sell inkjets to anyone. We don't even have a printer in our photo dept. We send the files out for Frontier prints or Lightjets. I have a fair idea of how long a c-print will last.....
Try the Preservation Calculator. you punch in the temp & rh of the room (or whatever the area where you store your negs)--and it gives you an estimate of the lifespan--until acetate film base would begin to fail. On the software version, there's a help guide that explains all sorts of concepts in deterioration and other factors like mold germination etc, and how you could extrapolate the data for organic materials in general. It's worth having a look at--and is a good tool in learning about how temp & rh play a role in all this. A real world example of this is the "stored alive" interactive on that climate notebook link above.
Opinions expressed in this message may not represent the policy of my agency.
BTW--the paper came from a study at the IPI--which is partially funded by RIT I believe.
Originally Posted by Jorge
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I agree, that is why I have never put too much faith in accelerated tests, but from the commercial point of view you would think they would want to say use the conditions found in 4 points in the US, high humidity/high temp, low humidity/high temp, etc, etc and try to make some sort of more realistisc test for "collectors" instead of museums.
Originally Posted by DKT
I am not talking about ANSI, ISO or ASA standards, that is different and I am sure very useful to a person like you who works in a museum and has the resources to mantain a specific environment.
Ah well, in the end who cares? I dont buy ink jet prints and never will.....I suppose caveat emptor is in order in this case. But I did find the article very useful and instructing.
Like I said though, caveat emptor becomes difficult when they give inkjets names like "Platinum".
As to RH, where I live the RH can be 15-20% one day and 80% the next depending on the weather. In AZ it WILL vary widely. So can sun exposure, temp, etc.
Even in more temperate climes, it can vary widely.
Example - A house heated by gas will have a higher RH than one that runs off of electricity. One that has no A/C will experience different conditions in the summer than one with A/C.
Which is why I say you should stick with what you know works.
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It's pretty simple though. almost everything likes cool/cold and dry. Not real dry--it depends on what the material is, you don't want to dry it out so much that it falls apart, but high temps, high humidity are the arch-enemies of storage. what you need is a worst-case scenario test, that would show you how bad it could get-- but this probably wouldn't make good ad copy....
again, it's kinda like the PAT. they stress the materials out. It's my understanding--vague--that plastic based materials can be destroyed in the process of the test. If the product has slip agents in it for example--like a plastic notebook sleeve. The plastic may be "safe" in that it won't cause any staining to the items inside. But the nature of the beast is, that under the right conditions--higher temps, humidity and pressure--the slip agents can leech out onto the surface of whatever is stored inside. It doesn't "harm" the item anymore than that you can't remove it, but, that's a finer point.......
One manufacturer had a disclaimer for awhile listing the ranges of conditions applicable for use of a product. It was basically the ANSI standards I posted above. Cool & dry. Cold. The disclaimer was a footnote on a website--the packaging doesn't mention these guidelines.
How much do you suppose they'd sell if they said you had to use it in conditions under 70 degrees F and 50% rh constant, and avoid excess pressure on the surface if items are stored within?
OTOH--very easy to call something "archival"....my pictures will last forever!
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But if you cool things the "dew point" or the point at where condensation occurs becomes lower. Seems like a double edged sword. Too cool and you precipitate moisture out of the air onto the subject. Too dry and you dry out the subject.
Screw it, I'm only going to work with etchings on titanium surfaces stored in abandoned salt mines....
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yeah--sure--forgive me here, but people are stupid....what else is new?
Originally Posted by Robert Kennedy
there's a c-paper on the market called a "sepia" print. polaroid makes a "sepia" film. manufactuers make storage sleeves that can stick to your film and still call them "archival". or..how about ads in photo magazines using public domain photos for stock? yeah, sure go ahead and order it from them & pay a usage fee! you can only get it for free from the Library of Congress and almost every archive in this country...
you could go on & on & on &....back to the beginning of photography. take daguerrotypes- they used to take tintypes--ferrotypes--and put them in Union cases--to sorta spruce them up --making them look like the more expensive dageurrotypes or ambrotypes. now, it's not unusual to find a tintype in a case, being sold as an ambrotype, just out of ignorance or some unscrupulous dealer....
Or frontier prints and lightjets? You'd be hard put to argue that an optically made print was somehow more longer lasting than one made on a Lightjet or a Lambda. If anything, this is the best digital/trad. output material there is. If you had to purchase a digital print from someone, and you were worried about it--you could do much, much worse than this.
The National Archives uses Lightjets for some of their work--check out their traveling exhibit, "Pictures of the Century". This was done on b&w rc paper on a Lightjet. The patron prints they sell are made by a group of contract vendors--almost every one of them uses Frontier prints. . The last update I read from Wilhelm for his book--he recommended c-papers like Crystal Archive over *any* b&w rc paper on the market.
My point is that things change. What was considered to be an unstable type of material, has now matured into a choice for some--could be the same for inkjets someday. I know another museum that sells inkjets to patrons as a cheap alternative to a regular print. They also use Pictro prints and dye subs. With the inkjets--they have a disclaimer that says the prints are non-permanent. I don't really have a problem with this--they have a whole scale of repro services, and this is on the bottom...it's the same reasoning for the prints we make on RC paper. I looked at a spreadsheet of materials the system I work for ordered last year. There was almost 20-25 times the amount of RC paper compared to fiber base. Things change.....
But platinum inkjets? whatever....it's just a marketing word. You would never be able to get the manufactuers to agree to a enforceable designation if they can't even come up with a standard test to TEST the products against in the first place.....
Definitely---Opinions expressed in this message may not represent the policy of my agency