Someone reminded me today of another fabric “experiment” that I did–one that looked at the affect of sunlight on the fabric. I again used the three samples — one an inkjet print on glossy photo paper, one a Spoonflower sample, and one printed on fabric using my Epson printer. These are the samples before exposure to the sun.
I taped three swatches to a sunny south-facing window for 4 months. Here are the results. (Note that the Spoonflower swatch below is different from the swatch above, but the colors are very similar. The other two swatches are the same ones in both photos.)
The Spoonflower fabric held up quite well to the sun exposure, but the ink jet prints faded significantly.
Color On Cloth 
Thank you for posting these very interesting comparison photos. I’m wondering whether the greater lightfastness of the Spoonflower-printed fabric is due to the inks used or to some other aspect of the printing process. (I’ve read that Spoonflower uses pigment-based inks, which are generally more lightfast than dye-based ones, but I don’t know how the various brands of pigmented or dye-based ink compare.)
A few years back (before Spoonflower launched) I bought a couple of used narrow-format Epson inkjet printers (model 740) and replaced their cartridges with a continuous-feed system of of tubes and bottles that could deliver various kinds of third-party (i.e., non-Epson) inks. I got some attractive results on fabric and on paper, and I loved having hands-on control over the printing process! Eventually, though, I put this experiment on hold. I found that I wasn’t printing enough to keep the inkjet nozzles from getting clogged with dried ink (especially the pigmented kind). Maybe, if I’d been part of a co-op, keeping the printers more active by sharing them with other people, things would have worked out better. Anyway, I’m glad we now have Spoonflower and its relatively lightfast inks as an option.
There is something gratifying in having control over your printing and the immediacy of being able to print yourself. I know many people are able to get great results using their own printers, such as Gloria Hansen (see http://www.gloriahansen.com/gallery.php?cat=1 ). I, however, haven’t been able to achieve the colors I want on fabric, unless I use a medium like Golden’s Digital Ground, and I don’t like the feel that medium adds to the fabric. You can see an example where I used the digital ground in my quilt “Marion and Charlie” in the Recent Quilts section (see https://coloronclothdotcom1.files.wordpress.com/2011/01/marion-and-charlie-detail-e1295710965741.gif ).
I have an Epson printer that uses pigment inks, and it’s pretty easy for me to get prints on paper which look very close to the image on my monitor. When I try to print on fabric, I spend a lot of time and money/ink trying to get the colors even close to what I see, but I never seem to get the results I’m after.