NGC 637 isn't on anybody's "best of" list. But it's easy to find, I guess that's worth something. Lynga describes NGC 637 as 8.2 magnitude with 20 stars penned into a 3'.5 area. My sketch records 19 stars at 190X in the 10-inch Newtonian. The brightest is a 9th magnitude GSC star just north of center. An 11th magnitude star stands sentry at the east field boundary. A pair of 10th magnitude stars marks the halfway point between the two. You'll find NGC 637 1.3 degrees northwest of 3.4 magnitude Segin, Epsilon (45) Cassiopeiae.