Peter Drew

The problem is, the prism used in a binoviewer is a beam splitter, this sends half of the light to one eye and the other half to the other eye. Therefore the eyes get only half of the input light and the brain, unfortunately, doesn't recombine the light. With binoculars or binoscopes you get the full amount of light in each eye, the perception, in this case is that the combined light appears to be brighter than a single telescope of the same size.

Just look at anything during the day Steve, then close and open one eye, the view doesn't noticeably get brighter or dimmer. The brain doesn't stack two images but likes the two sets of signal provided by two eyes rather than one signal and one noise to sort out.

I have a set of WO binoviewers and have been pleased with them and the supplied eyepieces.

It will clear as soon as Mars is well past its best and the current solar activity dies down.

The only way to reduce the friction to be overcome whilst adjusting is to prise off the side plates and back off tension on the grub screws and/or the tightness of the main pivot bolt itself. You should be able to rock the ALT portion of the mount by applying firm manual pressure. I have repaired/modified these mounts in the past by making and fitting a wedge shaped plate to the casting such that is presents a tangential face to the adjustment screw.

Hopefully!

Inspirational books, along with Webb's "Celestial Objects for Common Telescopes"

The bolts are not the origin of the problem, they are a consequence of the problem. The actual problem is a combination of factory overtightening of the DEC pivot and the unsuitability of the mount design profile where the adjusters operate in respect of the UK latitude. At our latitude and higher, the bolts operate a face that is ever increasing in slope rather than a tangential one. This causes the bolt to ride downwards on the slope thereby bending it if too much pressure is applied. Replacement with heavier duty bolts eliminates the bending but doesn't address the basic problem, they are no longer the weak link in the chain, this becomes the casting thread which can strip or possible damage to the adjustment face.

As a result, Bennu will collide with the Earth in 2216.

All my "stuff" is over 2 miles from the house. No, we don't have that large a garden!

Gong or nothing here either.

Up here in the NW we often use the main roads for kayaking.

Looking promising considering the precision of the test, a real star will confirm the exact alignment condition. At this stage it might be possible to just manually push the tilted component square. I had a look at my 90mm Bresser today, The objective cell is effectively separate from the dew shield and secured to the main tube by 3 screws, these are not adjusters and can be accessed only by removing the dew shield. Being an entry level telescope, Bresser would appear to have intended a factory set unit with no user adjustments.

Nice sketch, as usual Mike. What has particularly caught my attention with Mars this year is that every detailed report seems to include more and more named features that I've never heard of, let alone seen!