Thank you Stu, Nigel, Matt and Dean. All of your advice is most helpful. Stu, the dob has a solid tube and focus is closer without the extension tube (adapter). Nigel, we will certainly try all of your suggestions. Dean, I didn't even know there were two more stars inthe trapezium so I will have fun now trying to find them. Ditto for the homunulus. Matt, the image link is great and has made me realise that I am actually getting great viewing. It also made me realise that I have been looking at only a small part (the trapezium part) of this object. What I see is pretty much as shown in this sketch on the same site.
http://www.asod.info/?p=7671 I will have to try a much wider view. Dean, I will certainly try a deep sky filter.
Thank you all for sharing your knowledge.
Michelle
