A great idea, compact monoculars are easy to carry, most will fit easily into a small pocket so you
always have that magnification on hand when you need it. But what, if any, are the disadvantages ?
Well firstly, the same rules apply to monoculars as they do to binoculars. There are two numbers, for
example 10×25, telling you 10x magnification with a 25mm objective lens. Bigger magnifications are
hard to hand hold so you would really need to keep the magnification of a compact monocular to
10x or less. As for size of the front lens, if you want the monocular to be truly pocketable, then
25mm is as big as you can go. Smaller front lenses mean that you do not gather quite so much light
which makes them less effective in low light. For normal daylight use however, an objective of
between 20mm – 25mm would be perfectly OK and we would suggest looking for a monocular of 8x
or 10x with an objective lens of between 20 -25mm. 8×20, 8×21, 10×25 are popular choices.
Some people find monoculars less easy to use than binoculars, possibly because it’s not so relaxed
closing one eye, but after a little practice this becomes easier.
Zoom monoculars can be a good choice, for example 8-20×25, allows the magnification to be
changed from 8x up to 20x. For hand held use, it would still need to be kept at the lower end of
around 8x to 10x however you have the option to increase power to see details at a distance.
Some monoculars have an ultra close focus function which allows the instrument to effectively act as
a small portable microscope, useful for looking at details on plants or insect.
Visionary 8-25×25 Compact monocular with Ultra close focus
This is an example of a very versatile monocular.
8 to 25x variable magnification (use at 8x-10x for
normal observation) The 25mm objective is good for
most daytime uses and close focus to under 50cm is
great for plants and insects