Digital BW, The Print

Tim wrote:

>From John Cone's (Inkjetmall/Piezography) recent post
>on here "RE: [DigitalBW] Re: Septone system (LONG)"

>> FYI, EEM turned yellowish brown rather rapidly (at 100 hours)
>>in our tests
>> and we have abandoned it as an "archival" paper. It may allow
>> EPSON inks to
>> "test" better, but the paper discoloration is too gross to be
>> considered as
>> a long-term material. I would appreciate hearing your view on
>> that paper in
>> that regard and if you have seen that in your test

All I see in my testing is what I believe to be rather normal "yellowing" of
the optical brighteners, which is common with all such brightened papers.
EAM/EEM appears "normal" in this regard.

Note that in Jon's post he also observed, "Submitting silver prints to
accelerated light tests usually cracks their surfaces anyway."  This makes
me wonder about the test conditions.  Are his test conditions cracking the
surfaces of silver prints?   I have put silver prints in my tester for short
durations and never seen any surface cracking (also no fading).

Jon is using a Xenon lamp which I believe is very bright.  It may be very
hot also.  With an appropriate daylight filter, it can put out a spectrum
that is similar of daylight -- but that may include UV that is beyond what
my test samples are exposed to.  If the Xenon lamp is being used with no
filter, I'm not sure what the UV content of the light is.

I test with fluorescent light which is probably not as bright or hot, and
probably has a lower UV content.  Wilhelm also tests with fluorescent
lights, and is more careful than most about the temperature of the papers.

So, perhaps some of the differences we are observing result from the test
conditions.  High humidity and high temperature probably accelerate the
acidic reactions.  Perhaps higher UV is also a factor.

I think we all agree now that EEM/EAM is not "archival."  However, it still
has the best image quality per $ as far as I'm concerned.  So, it makes an
excellent and affordable paper for many uses.  It just has a limited life
that may be very limited in extreme conditions.

Paul
http://www.PaulRoark.com