I knitted this scarf for my wife. I created the pattern in Microsoft Excel. Shadow or Illusion knitting is a process of knitting or purling stitches of two contrasting colors to create a hidden image. The basics of shadow knitting can be found in the instructable I created here. The basic idea is that each pattern row is four knit rows.

Row # a - Color 1 - Knit across
Row # b - Color 1 - Knit on the white pattern squares, Purl on the dark squares
Row # c - Color 2 - Knit Across
Row # d - Color 2 - Purl on the white pattern squares, Knit on the dark squares

Move to the next row in the pattern and repeat.

I used Lion Brand Wool-Ease worsted weight yarn. The whole scarf is about 5 feet in length and took me about two weeks of evenings to knit. My wife (a music teacher) looked at it initially and asked, "What is it?" "A piano," I replied. She said what I hoped she'd say... "It doesn't look like a piano to me." So I held it up and said, "That's because you need to look at it from a different perspective." She spent the next five minutes raising and lowering it to see the pattern come in and out of focus.
JohnnyAwesome says: Jul 25, 2012. 4:20 PM
how many skeins of each color did you use?
stonesh says: Oct 2, 2011. 10:14 AM
I am new to shadow knitting and am confused to say the least. Is this pattern knit from top to bottom or bottom to top. The way it is numbered on the left would indicate top to bottom. Am I correct on how to read each row. Is it as follows?

1a R to L
1b L to R
1c R to L
1d L to R
ERNesbitt (author) says: Oct 30, 2011. 6:07 PM
If you knit top to bottom, left to right, you end up knitting it completely backwards and mirrored. Your interpretation is correct, though... Each numbered row has four rows inside it. Color 1 right side, knit across, color 1 wrong side, knit/purl. color 2 right side, knit across, color two wrong side, knit/purl...

Hope I haven't confused you further.
jahler496 says: Jan 11, 2011. 1:19 PM
wow, how cool! I have a ton of musically inclined friends who would love that! May I share with them?
ERNesbitt (author) says: Oct 30, 2011. 6:04 PM
Absolutely!
LaRue6358 says: Mar 28, 2008. 7:48 PM
It's beautiful! How many skeins of each color did you use?
ERNesbitt (author) says: Mar 30, 2008. 4:41 PM
A five foot scarf took about 1-1/2 skeins
mawwwm says: Jan 19, 2008. 2:09 PM
Both the scarf and the fact that a male knitted it, are so awesome....great job!
ERNesbitt (author) says: Jan 21, 2008. 8:11 AM
People think it's odd that I knit, as not too many men knit. But, I had to have something to do while my wife sits and crochets... So, I taught myself how to knit.
mawwwm says: Jan 24, 2008. 12:52 PM
well i think it's great....my boys are always fascinated and i think the youngest might let me teach him knit or crochet once his sports driven big brother leaves home this summer to go to college...but all of them have been curious with this and sewing and they've all had a chance to sew...as a coffee and tea shop manager i met a few older men who told me they knitted while in the service...i think it's cool....!
Lego man says: Feb 20, 2008. 7:36 PM
It is cool I like to knit to calm me down or for fun.
raycheshire says: Jan 21, 2008. 12:58 PM
I love it, simple yet really effective I think. The idea of a piano was really cool! Even better if you could actually play it- maybe you should build up towards it, you know work your way up.
ERNesbitt (author) says: Jan 22, 2008. 11:51 AM
Don't know... However, your name gives me a great idea for another scarf.
Zontee at Lion Brand says: Jan 21, 2008. 7:49 AM