By Harald Johnson

For the past six months, I've been engaged in an interesting project. It's called "window testing." Now, window testing is nothing new. Photographers and imagemakers have been doing it for years, decades even. However, there hasn't been much standardization or coordination about it, at least not in the photography world. And this is what my proposition is all about.

I was curious about how my choices of inkjet inks and media (paper) were affecting the longevity of my prints. Yes, I know all about Henry Wilhelm's "Print Permanence Ratings", and I devour each new report that comes out. But Henry mostly rates the recommended ink and media options from HP and the other major manufacturers, and I had other questions about a specific image I was working on. (I both sell and give this image away, so there are real-world implications here.)

--What if I put the wrong type of paper in my printer? Would I see a difference in print fading if I tested it?

--What if I had the right type of paper, but from a non-recommended manufacturer?

--What if I also tested the same image printed by one of those photo-sharing-and-printing companies?

--What if I included the same image printed in one of my books by offset lithography? I've always wondered about offset prints, which are commonly used by artists and photographers for long-run editions.

So here's how I set up my own window tests. I created a set of mini-prints on my HP Photosmart 8750 printer. All prints were of the same image, but each print was on different media. I also sent the image to Snapfish.com for printing. And I cut one out from my book Mastering Digital Printing, Second Edition (page 376).

Why the HP Photosmart 8750? First, I had one, and it was already set up in my office studio. Second, it's a popular dye-based printer, and I knew that I'd see results much faster than with a pigment printer. And finally, my image (taken underwater at a swimming pool) had a lot of blues in it, and this printer does a bang-up job with blues. My poolmates were clamoring for prints of this image, and I wanted to give them an eye-popping version. But I also wanted to be assured that it wouldn't fade away like posters in storefront windows do.

About six months ago, I hung the little prints on the SSW-facing window in my office. This window gets about 5 to 6 hours of direct sunlight each day, depending on the time of the year. The full blast of sun accelerates the test, speeding up the results. My goal was to do a relative comparison test of differently printed samples of a real-world image (mine) so I could say to myself, "this one faded less than that one." My test would actually simulate the display environment where the prints might end up, although it would do it in a more extreme way.

I recently pulled down my test prints to visually evaluate how they had held up after a half year of daylight exposure. I won't go into details about what I've found so far, but you can read about it on my ongoing online report.

Now, I have received some flak for this testing method. "Why aren't you using a standard test file?" "Why aren't you measuring before and after color change?" "Why aren't you controlling for exposure length." And more.

Some of these are good questions, and I'm attempting to answer them on the online report. But here's my point: What if lots of photographers/imagemakers started doing their own window tests and coordinated their reporting? So that my results could be added to thousands of others. Don't you think everyone could learn something from this? A thousand points of permanence self-testing light.

Of course, there would be some things to work out. Maybe we could use or adapt one of ASTM's test protocols. Maybe we could all use a common image or common image elements.

Basically, maybe we could standardize the tests in some way. Or maybe not. I don't know. What do you think?