This beautiful luscious red scarf is made with 2 different sizes of knitting needles, 10 and 17. This stitch is called Condo stitch and is straight garter stitch knitted alternatively with the 2 different sizes.
You can see how lacy the stitch can be in this photo where the scarf was held up next to a light in order to see through it. The suggestion is to use the size needle suggested on the yarn wrapper for your small needle and then go as big as you like, depending on how open you want the lace to be. I like this 7 size difference. My daughter made this fabulously soft scarf for her school secretary as a special gift to thank her for all the extra things she's done. The yarn is Cascade yarns, Baby Alpaca Chunky ( a bit pricey but this is a special gift).
Below is my start using the same technique but with size 8 and 15 needles and some rather nice high end wool. I say high end, because I rarely purchase fiber of this nature; but am treating myself. I've not made myself a scarf in about 5 years and those I have are looking pretty pathetic. I love the fun colors in this yarn. Crystal Palace Taos 100% wool. Daughter needed to take needles with her so I'll knit this off onto my round Denise needles and attach a different size to each end.