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In the early evening the crescent Moon was quite high in the south at 30° altitude. A chance to try the binoviewers on something other than the sun. I couldn't reach focus without the 1.6x GPC. Which meant a change of eyepieces and wasted time.
The 20mms for 220x[?] were impressive but not quite sharp enough given the thermal waves occasionally disturbing the image. Down to the 32mms and then quickly onto the 26mms for about 160x. Who know what the GPC is really doing to the magnification? I'm guessing at 2x until I can confirm it without the GPC and binoviewer.
It was fun "seeing" the moon as if from a modest distance. Rather than merely looking at it through a telescope with one eye. If I closed either eye the "hovering" illusion was gone. I watched as a crater rim and mountain tops, near a prominent crater on the terminator, crept into the light before my eyes.
I didn't sense any eye strain at any power I tried. I do badly need a decent focuser with slow motion focusing control and no slop. The locking screw on the old 2" Vixen needs to be tightened hard to stop it doing its own thing.
Despite the iStar working at f/12 the focus point is very sharp and short. I used a 1.25" TS star diagonal because I couldn't reach focus with the 2". More time wasted. The little star diagonal really struggled to hold the weight of the binoviewer and long eyepieces. I was literally having to hold them up while looking through them at some considerable power. I couldn't get "behind" the telescope to have the binoviewer sitting "upright."
I looked hard for false colour on the terminator, crater edges and limb and saw none. I had tried the Solar Continuum filter but didn't have quite enough light.
Alas, all to soon I was called in for dinner. The Moon was already much lower than when I had started. An attempt at a meridian flip started the wrong way again. So I had to manually park the telescope. I must be doing something wrong. Or, much more likely, have failed to enter a vital setting or parameter. Despite having repeatedly set Horizon to "0" I keep getting "Below Horizon" messages. I use a spirit level to confirm the tube is horizontal and regularly "Sync" on the parked position and the sun but it doesn't help.
Lessons learned: I need a real focuser which can easily cope with the weight of the binoviewers. I need some sort of physical support for the binoviewer to stop it sagging when it is pointing at right angles to the OTA. The problem is that any support would need to rotate around the main tube before being clamped. A tube ring with a support pole at right angles?
I need to know in advance which combinations of star diagonal and GPC will work and which definitely do not. Experimenting in the dark is time wasting. I may need to shorten the 7" OTA to allow the binoviewers to work without a GPC in the 2" diagonal. I can't use it on the Herschel prism either. Not without a GPC but usually want lower powers to monitor the whole disk. I routinely use my 32mm for ~70x on the Lacerta 2" solar prism because the sun then almost fills the field of view. The present, almost total absence of interesting features on the disk make use of the binoviewer in white light somewhat low priority.
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