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My observations
All 5 mains stars in Ophiuchus were easily visible to my eyes, with Beta & Gamma forming the lower set of hands to hold the Serphents tail and Delta & Epsilon being the upper hands holding the Serpens body, just below its head (Serphens Caput).
I mostly used my Vixen 115mm ED (FL 890mm), on an Eqz mount and 24mm, 15mm, & 7mm. For the Rho Ophiuchi Cloud complex, I used a 80mm (F6) Orion triplet. Then I started swapping scopes and used my Vixen 140mm.
Objects of interest.
Rho Ophiuchi Cloud Complex. Hartung's suggests in his book, Astronomical Objects for Southern Telescopes that this nebula can be seen. I had previously thought it appeared only in photographs...
Because of its large area, I used the 80mm triplet to observe the complex. The interesting double, Rho is certainly a great signpost that enabled me to know that I was looking at the correct area.
The 'complex' looked very large in the 80mm, even at 20x using a 24mm panoptic EP. Though it surrounded Rho, the larger and thicker part was to the East. It has a cold-grey tint and could be seen in its own right without needing to use a silhouette affect. That said, it was notable how fewer stars were seen in the area.
NGC 6572 Planetary Nebula. Its bright at Mag 8.1, but is only 16x13 arc seconds in size.
Using the 115mm at 37x (24mm EP), the aqua colour showed in the planetary even though it otherwise just looked like a star. The nebula took magnification well and looked best with a 7mm Delite, with which it appeared as small, bright and round.
RS Oph - Recurrent Nova; there have been 8 recorded outbursts, the last being in 2006. It is bright enough to be seen at minimum (Mag 12) and reaches around Mag 5 during outbursts.
This star was visible with the 115mm using only 37x. It, as expected, it is in its quite state awaiting its next outburst. There is a chart on P1245 of Burnham's Handbook that helps with identification.
NGC 6633. Open cluster. It apparently is large and bright.
A scattering of roughly 30 bright stars that crossed the diameter of field of a 15mm Delite EP (60x). Its shape is roughly rectangler rather than round. Nevertheless, it is somewhat difficult to establish if the fainter stars seen belonged to the cluster or if they belonged to the foreground or background
Barnard 72. The Snake Nebula. I have seen dark patches against the Milky Way, but have never previously tried to identify them.
I found this frustrating and resorted to using my 140mm to obtain a better view. I could see lanes in the correct area but could not follow the shape fully. It was best seen with at 53x (15mm Delite EP).
The Main Stars:
Alpha Ophiuchi (Oph): Rasalhague.
This is the brightest star in the constellation and it appears white.
Beta Oph:
This appeared orange, but the longer I viewed it, I also thought at times its colour sometimes appeared to be a deep-gold.
Gamma Oph: Muliphen.
This appeared blue-white.
Delta Oph: Yed Prior. A large (59 times the solar radius), but not massive (1.5 Solar masses) red-giant star.
I saw this as being medium-orange.
Epsilon Oph: Yed Posterior. Another red-giant. (10 times Solar raius, but 2 x Solar masses).
This appeared to be a light-orange.
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