Any film restoration experts here that can confirm if E6 is more archival than C-41?

I was staring at a 4x5 slide I developed last night, and I started wondering whether it or a C-41 negative would last longer. I did a quick search and found this YouTube video where the speaker references an issue of Photoklassica that stated (paraphrased) that E6 slides have an archival life of 200 years which is 3 to 4 times the lifespan of C-41. He mentions it at 3:20.

You could argue that I'll be dead long before my C-41 negatives noticeably decay. However, I do intend to leave a few treasures behind for posterity. I'm sure many of you do too. This information makes me more inclined to shoot more LF slides because they're comfortable to view. Medium format and 35mm slides are so much less enjoyable at a glance on a light table that I wouldn't mind sparing my sanity and sticking to C-41 for them.

Do any of you have good links to share (or personal experience) that confirm this claim by Photoklassica? I'm doing more research on archiving my work in general.

https://www.youtube.com/watch?v=oUt2SrFVj_I

Start here:

http://wilhelm-research.com/book_toc.html

Yes, it's almost 30 years old now, but it will still provide essential context for anything else you read or hear on the topic.

Only yesterday I posted a 1964 slide film show in Tiny Format

It will outlive all of us

Both CD-3 (E-6, ECN-2, RA-4) and CD-4 (C-41) should be inherently very stable - but CD-4 is much more active as a developer & with the right couplers is probably more stable overall - if the appropriate stabilisers are used for the relevant coupler generations. Do not forget that not all C-41 film was processed in labs using a full wash & stabilisation setup - plenty was processed in machines that were washless & stabilisation only - while most E-6 went through a full wash/ stabilisation process - this will distort most of the routinely facile takes on the relative 'stability' of the materials.

And remember that Wilhelm was essentially an amateur researcher - and that it was seemingly threats of lawsuits in the 1970s that had forced Kodak to stick to CD-3 in the 1970s rather than going to CD-6 - and that there have been several coupler generations after Wilhelm published, most of which had probably been in active R&D for up to 5-10 years before they launched. So, don't take him as gospel, interrogate his approaches properly - and where he may unwittingly distort the narrative. The other external factor will have been the rise of colour photography as collectible fine art (as opposed to commercial commodity) and that will have had a far greater influence overall than most might assume.

Don't read Wilhelm for "the answer" - a 28-year-old report cannot possibly provide a definitive take on the properties of today's materials, and the best methods for assessing stability continue to be a topic of debate. Do read it for historical context, for insight into the failure modes of color materials and the kinds of evidence that might be mustered for judging different aspects of stability, and to inform your thinking about how to critically evaluate claims made today.

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Originally Posted by Certain Exposures

...the speaker references an issue of Photoklassica that stated (paraphrased) that E6 slides have an archival life of 200 years which is 3 to 4 times the lifespan of C-41.

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I consider such an unqualified claim highly suspect.

Anecdotal reports of individual experience aren't going to tell you much that's useful - too many uncontrolled variables.

Find/get a copy of that Photoklassica International article claiming "E6 slides have an archival life of 200 years which is 3 to 4 times the lifespan of C-41"

Photoklassica International has become SilvergrainClassics
https://silvergrainclassics.com/en/

~What did the author of the article in Photoklassica International used to support the claim of "E6 slides have an archival life of 200 years which is 3 to 4 times the lifespan of C-41" _?_

Not a lot new with film technology as film technology is a mature technology in many ways and it's best days have passed.

What is well proven, Kodachrome properly stored last a good long time. Color transparency films of old were not as stable and fade resistant as newer generations of color transparency films. E6 processing will impact the stability of the color transparency film, one factor not often considered these days of E6 processing via home DIY kits.

It is generally accepted the last generation of E6 color transparency films and processing had good stability over time, typically better than C41. No news there.


The Toy Story ... story:
https://www.romper.com/entertainment...aternity-leave


Consider this article:
https://filmmakermagazine.com/96996-.../#.YhfSFxPMJI4


Bernice

Hmmm .... Sounds like quite an expert. Did he actually live over 200 years to make that "archival" assessment about E6 slides; or if otherwise, where did he acquire a 200 year old color slide? Talk comes cheap. And the problem with generic stereotypes about C41 is not only that some of those films have significantly improved in recent decades, and that in the past, a huge quantity of color neg film processing was done by quickie mini-labs and so forth which really cut the corners in terms of quality control, proper washing etc.

Even with some of the best track records, like Kodachrome, IT ALL DEPENDS on both the quality of the original processing, and especially the STORAGE CONDITIONS, as well as how much projection a slide might have suffered. And overall, "archival lifespans" based on extrapolated 24 hr torture tests in special aging chambers are, at best, informed guesses involving only a limited set of variables. Take em all with a grain of salt.

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Originally Posted by Drew Wiley

Hmmm .... Sounds like quite an expert. Did he actually live over 200 years to make that "archival" assessment about E6 slides; or if otherwise, where did he acquire a 200 year old color slide? Talk comes cheap. And the problem with generic stereotypes about C41 is not only that some of those films have significantly improved in recent decades, and that in the past, a huge quantity of color neg film processing was done by quickie mini-labs and so forth which really cut the corners in terms of quality control, proper washing etc.

Even with some of the best track records, like Kodachrome, IT ALL DEPENDS on both the quality of the original processing, and especially the STORAGE CONDITIONS, as well as how much projection a slide might have suffered. And overall, "archival lifespans" based on extrapolated 24 hr torture tests in special aging chambers are, at best, informed guesses involving only a limited set of variables. Take em all with a grain of salt.

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Ah, c’mon. It’s common practice in industry to perform accelerated testing …. Thermal cycles, accumulated UV exposure levels, etc… whatever environment is relevant is accelerated to quantify longevity without having to actually wait long times.

Quote:

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Originally Posted by Drew Wiley

Hmmm .... Sounds like quite an expert. Did he actually live over 200 years to make that "archival" assessment about E6 slides; or if otherwise, where did he acquire a 200 year old color slide? Talk comes cheap. And the problem with generic stereotypes about C41 is not only that some of those films have significantly improved in recent decades, and that in the past, a huge quantity of color neg film processing was done by quickie mini-labs and so forth which really cut the corners in terms of quality control, proper washing etc.

Even with some of the best track records, like Kodachrome, IT ALL DEPENDS on both the quality of the original processing, and especially the STORAGE CONDITIONS, as well as how much projection a slide might have suffered. And overall, "archival lifespans" based on extrapolated 24 hr torture tests in special aging chambers are, at best, informed guesses involving only a limited set of variables. Take em all with a grain of salt.

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The image permanency institute has been doing accelerated age and archival testing for decades, they worked hand in glove with EK from what I remember.

They declared that RC prints processed correctly are more archivally stable than a fiber based print, and crystal archive prints the same thing.

Wilhelm was at his best when he was examining older movie film stock and so forth, where there was an actual track record of storage conditions and projection, etc. That was his key assignment anyway. I've done a great deal of my own testing, under various conditions, and remain quite skeptical of many conclusions, especially marketing-based over-optimism. For example, identical Ciba prints of mine kept away from UV even framed on walls look nearly brand new 30 years later; but those getting direct sunlight part of the day look like they needed to be embalmed a decade ago, kinda that "walking dead" look. It's all relative.

I recently took repossession of a number of large framed Crystal Archive Super C prints of mine exposed to less than ideal artificial light 18 hrs a day, plus a certain amount of overhead skylight sunlight. I originally overprinted them so that they'd look nearly perfect right now, 15 years later, and they do ... but another 15 years, under those same conditions, that would probably be the acceptable limit - 30 years total, not 70 like Fuji claims, or 200 like some galleries claim. I don't know how long those would have kept in dark storage. I might not live long enough for that answer. But given my extensive personal background with industrial pigments, architectural color consultation, and its own analogous kinds of accelerated aging tests, I stick to my original remark, "take it all with a grain of salt". Too many snake oil salesmen out there. Inkjet is no exception.