D413 is "A cluster of small stars, with a bright star in the preceding side. A very considerable branch or tail proceeds from the north side, which joins a very large cluster."
This OC in is the nebulae NGC 6188 which was imaged by Paul Mayo (PhotonCollector)
http://www.iceinspace.com.au/forum/a...4&d=1190883235
The cluster is on the right in the image. The nebulae was found by John Herschel, it is an easy object in a 12" scope with a UHC filter.