I believe that the images are self explanatory. The Saddle Road is, nowadays, in superb, perfect condition. You definitively do not need a 4-wheel drive to go to the top (Summit) of Mauna Kea, unless there is snow. The only problem might be with US cars having automatic transmittion as not all of them allow for low-gear mode in order to make a safe descent. For climbing with a 2-wheel car you might want to disable traction control. Anyway, I decided to make THEM a favor and rented a Jeep (I enjoyed off-road driving on other parts of the island anyway).
The only real attraction, apart from the fact that you are at very high elevation and surrounded by many observatories, was a well in advance scheduled visit of Subaru Telescope. The excursion took about an hour and was definitively worth it. From the rest of observatories, there’s only few things to see at the Keck twins and nothing else.
I had a plan to make some astroimaging there, but it was really cold up there and, I would have to let my wife alone and ask her for driving down in the evening and back again in the morning to pick me up at some place hidden from everyone where I would shoot the stars with my ultra mobile astro setup (startrails, timelapse movie), but it simply was not doable on a honeymoon trip. Therefore, my plan B, was to go to Mauna Loa instead (about 3100m elevation) and wait until evening to see if there would be a clear sky during night. It turned out that there’s always cloudy near the Weather station so I decided to go back to Mauna Kea (near VIS) and climb a nearby peak by foot myself. There was still half cloudy that night. The biggest disappointment was seeing the billion of cars descending Mauna Kea in the evening. Ugliest face of MASSIVE tourism.
I made couple of shots with my DSLR that I am lazy to process so I won’t probably ever publish them.
Here, you can find couple of daylight images from the trip:
http://www.astro.cz/galerie/v/uzivatele/Konihlav/Havaj-MaunaKeaLoaKea-2013/
In the end – at least – it was a nice experience – just being there!