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Rho Cap - interesting binary that's been getting wider in recent years. I looked through my observing notes and found I'd not looked at it since 1997 (!!) despite having it on a list of changing pairs to follow up. This year it will happen.
Back in '97 I found it a tight pair, 1.3" apart at the time, instead of 1.8" now; and the 2 magnitude or so brightness difference makes it tougher. Anyway, in '97 it was a neat split at 330x with a 7-inch refractor on a night of good seeing. The secondary star was visible at 180x, but not as clean or clear.
I'd tried it the previous night without success, but the seeing on the previous night was not at all good; on the successful night, I rated the seeing as very good.
Seeing conditions make a very big difference with these tougher doubles, especially the unequally bright as well as close examples.
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