Inkjet printing is one of the technological success stories of the last decade. Even over the last five years, inkjet printers have gone from producing barely adequate output the marketers would define somewhat optimistically as ‘near photo quality’, to prints which in many cases are better than what’s possible on conventional photographic paper.

 

Inkjet printing is one of the technological success stories of the last decade. Even over the last five years, inkjet printers have gone from producing barely adequate output the marketers would define somewhat optimistically as ‘near photo quality’, to prints which in many cases are better than what’s possible on conventional photographic paper.

Of course it’s not just the printers which have improved, but the entire printing system: higher resolution and more ink channels from printers; better inks; and specialty papers for producing true photographic quality prints.

The Achille’s Heel of inkjet prints has until recently been their tendency to fade virtually from the moment they drop into the output tray. Now the ‘big three’ in inkjet technology – Epson, HP and Canon – are beginning to get serious about developing products which their customers can depend on to stand the test of time.

For ‘fine art’ photographic prints or simply pictures of cherished family occasions, quality over time may be just as important as quality at the time of creation, and enthusiast image-makers need to inform themselves of what combination of printer, ink and printing media will last – preferrably before purchasing a printer!

There are a lot of marketing claims being made by the various vendors. ‘Better than photo quality’ claims Canon of its photo inkjet printers. ‘Lasts for 100 years’ claims Kodak of its inkjet paper. Sorting the facts from the hype is a devil of a job – and the devil, as they say, is in the detail!

There are no ISO or ANSI standards for inkjet printers, papers and inks, which has created an environment where marketers can put the best possible gloss on the performance of their particular product.

A topical analogy is fuel consumption figures for motor vehicles. There are standardized tests to measure litres used per 100 kilometres that all manufacturers adhere to, so buyers are able to make fair comparisons on consumption data. If every car manufacturer were allowed to conduct its own tests, the world fuel crisis would (on paper at least) be solved overnight. V8 4WDs would miraculously start running on the smell of the proverbial oil rag!

The Guru of Permanence

The Wilhelm Imaging Research Inc (WIR), founded by Henry Wilhelm and Carol Brower Wilhelm, was initially established in the 1980s to conducts research on the stability and preservation of traditional colour photographs and motion picture film. Henry Wilhelm had been researching photographic image preservation for two decades prior to the establishment of WIR.

Among other achievements, he helped Martin Scorsese win a battle with Eastman Kodak and Fuji to increase the stability of their motion picture film, and recently designed a sub-zero preservation facility to permanentlyprotect Bill Gates’ priceless Corbis photographic collection of 11 million photographic images.

Until Wilhelm’s ground-breaking research showed otherwise, the general assumption was that conventional colour photographs had similar keeping qualities to black and white, when in fact some colour papers, Wilhelm proved, deteriorated in just months when exposed to moderate levels of ambient light.

In 1993 Henry and Carol Wilhelm published an exhaustive 744-page book, The Permanence and Care of Color Photographs. The findings in this book ranked Fuji colour paper in particular as far superior to Kodak’s in terms of image life.

Now Henry Wilhelm has moved on to new media, particularly inkjet.

WIR has become the de facto international authority for testing inkjet and dye-sub systems in the absence of accepted international standards.

This time Kodak and Wilhelm have a disagreement about Kodak’s Ultima photo quality inkjet paper. Kodak conducts accelerated light stability tests using an illumination level of 120 Lux (UV filtered) over 12 hours per day. The Wilhelm Institute, and the rest of the inkjet industry, used a standard of 450 – 500 Lux. While 450 Lux is the brightness of an office or kitchen environment, 120 Lux is pretty gloomy.

Using its lower light measure, Kodak is able to claim that its paper will hold an inkjet image – from any current generation inkjet printer and ink combination – for 100 years. Wilhelm counters by claiming that if this test was applied to Epson Picture Mate prints, they would have a life between 500 and 800 years; 1000 years for a print from an Epson Pro 4000 on its best paper!

‘Inks ain’t inks’

Third party inks are also problematic. Last year PC World magazine conducted a lab test on a range of cheaper “clone” inks in a number of high-end printers and found the best of them lasted for just four years. Moreover, the black inks in particular often clogged up the printhead nozzles.

Kodak and other third-party suppliers are in a difficult position in the inkjet market. It’s fairly clear from Wilhelm’s research, the advice he shares at international seminars and conferences – and sheer commonsense – that the best lifespan results are achieved when printer, ink and paper all come from the same manufacturer: They are then ‘made for each other’. A manufacturer’s ink is designed to chemically bond with special coatings on the surface of the paper.

For example, WIR testing indicates that the A4 Hewlett-Packard Deskjet 5500 used in its six-colour Photo Mode produces prints which last for 73 years when using HP Premium Plus Glossy Paper, but just 17 years using Kodak Ultima Glossy Picture Paper. (This is the same inkset used in the HP Photosmart 7960, reviewed in this Guide)

Wilhelm has been on his own steep learning curve when it comes to inkjet printing. In an early test on Epson inkjet papers, his predictions of a 10-year life were woefully off the mark, with prints deteriorating in just a few months. At that stage no one was aware of other environmental affects that impact specifically on inkjet media but not silver halide, in this case the urban pollutant, ozone.

WIR now has a more sophisticated understanding of the peculiarities of inkjet, and has ‘image-quality-loss metrics’ for a range of variables besides light and ozone:

  • Resistance to surface abrasion
  • Humidity fastness: colour change and/or loss of sharpness (Wilhelm reckons Kodak squibs on this measure, too)
  • Thermal degradation and stain: dark storage stability
  • Water fastness and ‘wipeability’ when wet
  • Stability of fluorescent brighteners if present in print paper
  • Short-term colour drift
  • Resistance to contact with plastics
  • Resistance to fingerprints over time after finger contact.

It’s clear that the questions: ‘How long will it last?’ and ‘Which one should I buy?’ are by no means clear-cut, and not likely to get any clearer in the immediate future.

A regular visit to the WIR website (www.wilhelm-research.com) is probably a mandatory first step in keeping abreast of the technology as new products are constantly being released and tested.

Dye Vs Pigment

Until very recently there was a clear trade-off when comparing pigment and dye-based systems, which boiled down to Epson (pigment inks) on the one hand and HP and Canon (dyes) on the other.

Pigment based inks are longer-lived, but don’t (or didn’t) offer the extended colour gamut of dyes. They were primarily used for outdoor display applications because of the twin virtues of water resistance and permanence in bright UV lighting.

Now Epson has its UltraChrome pigment system which it claims has a vastly improved colour gamut – twice as good as its standard pigment inks and better than colour photographic paper.

This is the ink set it uses in it’s Picture Mate printer for making postcard-sized prints.

Although its Wilhelm Display Permanence Ratings are lower than those of the extremely stable Epson Archival pigmented inkset available with the professional-grade, 6-ink Epson Stylus Pro 10000 and 10600 wide format printers, the UltraChrome inkset actually produces prints with a larger colour gamut and higher contrast range.

HP has recently announced new dye-based ‘Vivera’ inks, which it says when used with recent HP inkjet photo printers, delivers the brilliance and high quality of dye and the traditional longevity of pigment inks. Unfortunately, these inks are not compatible with older HP machines. The combination of Vivera prints on HP Premium Plus Photo Paper will last 82 years when made with three- and four-ink printers, and 100 to 110 years with six- and eight-ink printers — life expectancies on a par with the Epson UltraChrome pigment-based inks and dedicated papers.

Canon has also started to get serious about permanency. Along with it’s new Pixma printer range (reviewed in this Guide) it announced its high-end Photo Paper Pro paper “offers 100 years performance, producing prints that last well over a lifetime when stored in a photo album” – when Canon inks are used.

Of couse, some prints don’t need to last forever, or even until next year. The best papers cost more, so the cost-conscious print maker will have cheaper stocks on hand for everyday printing and trial runs, and keep the ‘top shelf’ stuff for their best work.

Here are a few points to keep in mind if production of long-lasting photographs is important.

  • Instant dry ‘microporous’ high gloss papers are particularly prone to the effects of atmospheric pollution in combination with (ubiquitous) dye-based inks. If you rub your finger across the paper and it grabs or squeaks it’s probably a porous paper. There are some other glossy papers that are ‘swellable’ – they take far longer to dry but provide a greater amount of protection from atmospheric gases. (But on the other hand are not as water-resistant.) Be wary of paper that promotes itself as ‘instant dry’ unless you are sure it’s not a porous variety.
  • While the use of pigment inks with microporous glossy papers is satisfactory in terms of image permanence, they can exhibit a variable glossiness over the surface – a function of the density of the ink.
  • Fingerprints are no more a permanence issue for inkjet prints than traditional photographic prints.
  • Pigment-based inks are superior in terms of permanence and water resistance to dye-based inks, but most have a poorer colour gamut and lower saturation. (With the exception of Epson’s new(ish) UltraChrome inkset.)
  • Dye-based inks are particularly susceptible to ‘short term colour drift’ in high humidity environments. The colours will change over weeks or months.
  • Six- and seven-colour systems have tended to be less stable than four-colour, but the latest six-ink system used in HP Photosmart printers is actually more stable than HP’s four-ink system. New six/seven-ink printers developed specifically for photographic printing are likely to overcome the failings of earlier inks as image life becomes a crucial design criterion.
  • Especially with dye-based printers, choice of paper has probably the largest impact on permanence. HP’s latest Vivera photo inks and Premium Plus Photo Paper is probably the best dye-based combination going round at the momen, according to WIR.
  • Third-party papers that are advertised as being suitable for all printers are, almost by definition, not optimised for any particular inkset or printer.
  • Most manufacturers of third party inks and papers pay scant attention to image permanence issues. (Kodak is a notable exception here, notwithstanding debate about its testing methods. There are also some premium archival stock manufacturers in the fine art segment of the market who would dispute this claim.)
  • Brilliant white papers use brighteners that fluoresce blue and absorb harmful UV radiation – a paper with less brightener will have a longer life – so don’t be put off by yellowish-looking stock.
  • ‘Mixing and matching’ papers and inks is far more risky with dye-based inks than pigment-based inks.
  • The ‘Big Three’ in printer technology, HP, Epson and Canon, are the most advanced in the field of image permanence.

The measure of just how good some of the latest inkjet/paper combinations are is that the best of them far surpass the keeping characteristics of the best of the “true” photographic papers, Fuji Crystal Archive, which is rated at just 40 years behind a glass frame.

FEATURED LINK: www.epson.com.au for all your printing needs.