|
Wavytone is right: if you want high power you need a quality telescope. Zoom binoculars are compromises at best, and I suspect it is highly unlikely you would get a sharp view with these at 100x! There would also be a fair bit of false colour; which is why the suggestion of a triplet or ED lens.
Regarding the exit pupil size: a lot of people would say around 1mm is the smallest you should go for sharp and relatively bright high power views.
However, you can go smaller if you have a top quality objective lens: my Tak TSA 102 for instance can very easily cope with >200x, which means an exit pupil of 0.5mm or less.
In fact the old rule of up to 50x per inch of aperture (or 2x per mm) for a top quality scope gives an exit pupil of 0.5mm...
|