I recently purchased a used Binotron Supersystem with 21 mm eyepieces. Last night was the second time I used it under the stars. Both nights, I primarily observed Saturn and Jupiter. Seeing conditions were average, maybe a little above average.
I'm trying to figure out the best way to focus the system. Like everything, there's a learning curve. To help shorten the curve, I'm wondering if people would like to share their techniques and experience.
The system can reach focus in all my scopes. My trouble is getting both eyes focused and knowing that they are focused. With the planets, the system can be in perfect focus but planetary details can come in-and-out of focus due to seeing fluctuations, so I find it hard to know when my focus is optimal for the conditions.
My current strategy for focusing is to use the telescope focuser to reach coarse focus. Then, I close or cover my left eye while I focus the right eyepiece with the Binotron eyepiece focuser. Once the planet looks focused, I close or cover my right eye and focus the left eyepiece with the Binotron diopter focuser. Most of the time last night, I would be satisfied with the individual eyepiece focus, but disappointed with the focus of the two-eyed image, which showed less detail than the individual images.
Now, there were a couple of moments when everything seemed well-adjusted and I had the impression of depth perception with Saturn or Jupiter. It was a very pleasing image, lots of detail to observe. Eventually, I would fiddle or fuss or change magnification with the power switch to see how far I could push the image. Then, I would struggle to get back to the focus I had.
Is my problem that I am using a planet to judge individual eyepiece focus?
Should I try focusing my right eye first, then adjusting the diopter focus for the left eyepiece with both eyes open until the view looks best?
Once I have the diopter accomodation set between eyepieces, is there any reason to touch the binoviewer individual eyepiece focusers again? Should I just use the telescope focuser for the rest of the night (unless I change eyepieces, of course), and avoid the back-and-forth right-eye-left-eye shenanigans?
What have you found that works for you?