Three years ago, I set up my 17.5" in my backyard in Sydney to have a look at M42 after having sketched it the day before with my 8" f/4 dob. The day before seeing wasn't much chop and I struggled to see Trap. E & F. The next day, what a difference in seeing! This time seeing was rock steady and on display were Trap. A, B, C, D, E, F, G, H & I
All from suburban Sydney.
I wasn't expecting this multitude of additional Trap. members, and I began a mad search for additional info on these fainter stars. I also asked here on IIS for info on the Trapezium members. At the time I just couldn't find a good enough resource about the Trapezium and I wasn't aware of H1 & H2. In all honesty, I'm not really fussed.
http://www.iceinspace.com.au/forum/s...ight=trapezium
The trick is all in very steady seeing. Of course I've looked at M42 many more times since, but I've never again managed to hit upon the same quality of seeing conditions to see the fainter Trap. members even from dark skies. The sketch below I did that night with the 17.5".
Alex.