Here is the bottom line: your photographic prints ARE going to change over time. Period. You may be able to put that off for maybe 1000 years, provided you are so famous that you can get together with Corbis and Bill Gates, and get them stored in sub-zero temperatures underground in the Corbis photo vault in France.
Chances are, however, if you’re that good, you’re not reading this blog.
For the rest of us, here’s the thorny patch of considerations to be dealt with. Pick your poison.
The paper itself will yellow with age The inks will fade, and change color. If the paper has optical brighteners added, they will lose fluorescence, (causing the paper to look less white.) Ozone will attack…. ultra violet will attack. The very light you need to even see the print will attack.
Don’t feel bad, however: no work of art has passed the centuries unscathed, and the longevity of digital prints produced in 2015 is, frankly, phenominal: in some cases over 200 years. (Compare that to the Kodak snapshots from the ’60’s and ’70’s which were closed up in the family album, and nonetheless three years later were a solid shade of magenta or even green.)
In fact, compared to previous color photography (and even B&W: think silver gel or cib) the situation is nowhere as bad as you think it is. While the number are all over the map, and vary according to paper and (everything above) here are the averages for Epson K3 inks:
stored in the dark: 250-300 years.
protected by UV filter: avg 150 years
not protected: avg 50+ years.
(See things really are not that bad: over 50 years for an unprotected ink print. Kodak should have been so good.)
That said, the bottom line still is that your photographic prints are going to change. If you want your viewers to see it as you see it, invite them over on the day you print it.
Now, of course, that’s nit-picking, but I’m trying to make the point that things well beyond your control (and some things within your control) are going to change your print.
What with all the conversation about optical brightener additives, you’d think that’s all that matters.
Hardly. I’ll get back to OBAs shortly, but let’s cover some of the other issues.
This will come as no surprise to anyone at all: the sun fades things. Your drapes; your house paint; your car; your rugs… name it. And while the sun is most egregious, any bright light will do pretty much the same damage, and the brighter the light, the faster things will deteriorate.
The paper you use will yellow, and the brighter the light, the faster this will happen. (Nope, not even talking OBAs here – paper yellows with age.)
The environment plays a huge part in all this: not only light, but humidity; air-born contaminants; ozone levels (particularly those electrostatic “air cleaners”).
And wouldn’t it be nice if all this were at least quantifiable? “X amount of ozone does Y amount of damage…” but it’s not. There are various blends of inks; there’s dye vs pigment; there are hundreds of different paper formulations, weights and coatings. Some ink colors are more susceptible to one of these things than others (colors or things) – different colors will change at different rates, throwing the whole balance off.
It’s enough to make one simply give up.
But don’t, just yet…
There are some guideposts, and some things you choose between to at least make the inevitable change follow your preferred course (…with any luck.)
Cheap paper is just that: cheap. Expensive photo paper will be more stable and long-lived, and exhibit more uniformity and quality. 25-cent a sheet paper isn’t going to last like $5 a sheet paper.
But now, let’s get to the promised OBAs.
OBAs (Optical Brightening Agents) work the same, whether they are in your laundry detergent or your photo paper: they absorb light and that energy causes them to emit light, but in a specific wavelength we see as blue. Right: blue, not white (which is the combination of all the visible wavelengths.) We perceive a bluish tint over white reflectance as “brighter” than the white alone. Well, you can see that after being blasted with light, the emission levels will fade with time, until eventually, the OBA ceases to emit the blue light. At that point, the paper substrate’s natural color is all that’s left. (OBA’s are naturally colorless, not white.) If you need an example, just think of the luminescent hour markers on your wrist watch. Exposed to bright light, it glows, but then it rapidly fades, and that color now looks faded, if not totally different.
Let’s come back to that “buy expensive paper” thing, above. Better paper substrate (the “paper” itself, without coatings of any kind) will be not only physically uniform, but will have been made as white as possible, almost always by using simple bleach to get out as much of the “yellow” native to the pulp as possible. Some paper can become quite white without any OBAs at all.
But none can reach the same levels (at least in 2015) as those papers using OBAs.
And the more white the substrate, the less OBAs are needed, and the better the paper will look when the OBAs are depleted. Yep: to confuse the situation even more, there are greater and lesser amounts of OBAs added to different papers. (Cheaper photographic papers, will use more OBAs to even out inconsistencies from batch to batch, and disguise lower quality substrate.)
And here’s a great Catch-22: putting any kind of glazing (glass or plexi) over an image will change it. You may think that stuff is clear, but it’s not. Ever look at glass on edge? Green, isn’t it? The fact is that by covering your image, you are indeed offering it -vastly- more protection… but you are also changing the colors (or the grays) either directly or in reference to one another. (Test it yourself; it’s easy enough.)
The Catch-22 is this: if you choose to use OBAs, which are activated by ultra violet light, and then put your image behind plexiglass (any plexiglass, not just UV plexi) you’re cutting out at least 90% of the UV rays… completely defeating the purpose of using that paper in the first place! (Glass only cuts out a few percent of the UV, so at least there’s a way around the issue, assuming you want glazing at all.)
Back to the paper, however… In inkjet printing (at least most of it) the white in the paper is the absence of ink; it’s the paper’s white showing thru. (There are some printers with white ink, but so far, they are not true photographic quality.)
Further, the paper’s degree of white affects not just the whites in your image, but the entire image itself. Inks are not 100% opaque: the background shows thru. Imagine printing one of your photos on black paper if you don’t see this point yet.)
The same image printed on “natural” paper (without any OBAs added) will look significantly different when printed on a paper using OBAs. Papers with OBAs have more of a sense of being illuminated from behind; of light surrounding the subject, than images printed on natural paper. (In fact, if you got how OBAs work, this is to some extent entirely true: the OBAs emit light.)
Now, that effect of “being lit” is more obvious when comparing a print on a non-matte (usually called resin coated, or rc) paper with the same image printed on a matte paper, but in this case, it’s how the paper reflects the light, directly (rc) or scattered (matte paper.) The “mood” of an image printed on matte is entirely different from the same print on rc paper. The choice is made by the subject itself, and how the artist relates to it.
The same effect, albeit to a lesser degree, is seen between papers of the same surface but with or without OBAs.
So: to use paper with OBAs or not?
Part of that is easy to answer: you’re the artist – does the image call for really bright whites or not? Even if there are no whites in the image, does the image look best if the ink rests on a whiter paper, or is, in either of these cases, a more subdued white/background suitable?
Whites look different on paper with OBSa vs without. The inks themselves look different depending on your choice of paper. If you’ve done enough printing, you know this already. And if you’re discerning enough to see that, then you also know that different images call for different papers. Satin? Gloss? Luster? Semi-Matte? Matte? Watercolor? Canvas? OBAs or natural?
Those are choices you have to make first. It should, however, be fairly obvious that if the image doesn’t benefit from paper with OBAs, go for the natural paper. Bingo: issue resolved. Go have a nip of Scotch: we’re done here.
Here’s where it gets sticky: if the answer to that question is that OBAs are needed to match your vision for this image, then do you use them or not, opting instead for longevity?
Perhaps I can rephrase that in more stark terms: do you want 50 years of viewing your image in exactly the form you desired, or 150 years of viewing as not quite correct?
The only way you’re going to get the best of both worlds, 150 years of exactly right, is to change your vision in the first place, and alter the image to be satisfactory to you with a natural paper. If you’re not willing to alter your vision, then (at least in 2015) you’re stuck making a no-win decision.
Naturally enough, I get the question “what do you do?”
So, I’ve split out my personal choices here, following the gist of the main article.
Here’s my take: it’s my vision, and I spend lots of time getting a print that reflects it to my own satisfaction. Therefore, I’m not interested in glazing it unless the client asks for it, or it’s going on display where the public can (and will, guaranteed) touch it. If the gallery demands it, so be it. But I much prefer “the unvarnished truth” – my print, unhindered by glass or plexi, and absent different instructions, that’s what I will deliver.
My personal take is simple: the art is up to me; how the buyers wants it displayed is really up to them. If a collector wants it face-mounted, or framed behind plexi, I’ll do it. I’m not on a crusade here. I want to share my art as best I can, but the other guy is paying the bill, and it’s going in his house, not mine.
Speaking of face-mounting (“Diasec”) – oh gads, what a fad. Next it will be backlit, like a Grand Central Station marquee. Yes: it looks so…. much more saturated and sparkly. Or you could just print the image on glossy paper and be done with it. Diasec was designed for the advertising industry to put images in public places. It looks like it too. Pure decoration; not art (regardless of Gorsky or Sherman.)
OBAs in paper: I’m not afraid of them. Paper-makers use varying amounts, and are enough aware of the issues to often indicate at 2 or 3 densities: light, medium, or strong use of OBAs. If I can find a paper with no, or little OBAs I’ll use that if the image requires it, and the other criteria (surface etc) are met. I let the image guide me, not some preconception about paper.
Obviously then, in order to make this choice, I fall squarely in the camp of “50 years of accurate viewing”, and am willing to leave the next 100 years to fate.
And there’s one more completely pragmatic thing: in 50 years, my buyers and myself will both be dead, and the issue will be resolved as far as we are each concerned.