This next knitted sample was developed from a picture of tree bark taken on a visit to an Abbey. I used a filter in Photoshop to generate the image on the left and then traced it onto tracing paper (the image on the right).
I found a pattern in one of my stitch library books that looked a bit like the tree bark.
This gave me the idea that I could develop a knit and purl pattern to look like the bark. I copied the tracing onto stitch related graph paper and in fact generated 2 graphs as shown below.
One graph had more variation between the knit and purl stitches than the other but I ended up knitting the lower graph. When I knitted the sample I decided that I would use the side that was mostly stocking stitch (the knit stitch showing) as the right side.
This was the resulting sample which has been knitted with a cable edging. However after knitting it I think the reverse side would have worked better, so here is the sample with the reverse side showing.
Knit and purl patterns can be viewed from either side but often the purl or reverse stocking stitch side can look more interesting as the purl stitches visually push forward and vertical runs of knit stitches. Putting the cable edging onto the sample stops it from being completely reversible.