What are the disadvantages of a reflecting periscope?

Answer 1

The main disadvantage is that it does not have the advantages of a prism periscope.

1) Glass prisms do not produce multiple reflections

2) Glass prisms do not have exposed silvered surfaces which can be damaged

3) Depending on your arranges, if not the image will not be inverted.

Answer 2

advantages helps us to see above crowds and its usesdisadvantages does not work in misty weather does not work when screen covered with dust

Answer 3

One disadvantage of a reflecting telescope is the typical style in use today, the Newtonian style reflector, utilizes a secondary mirror to bounce the focused light from the primary mirror out the side of the tube for focusing (otherwise the viewer's head would be in the light path). Both the secondary mirror and the support apparatus for it - usually called a 'spider' assembly (or sometimes an optical window) - cause diffraction as they are in the light path for the primary mirror. This can cause a loss of contrast and 'spikes' to appear on brighter stars and/or planetary images in the eyepiece. The larger the secondary mirror and thicker the spider vanes, the more loss of contrast occurs; conversely, the smaller the secondary and thinner the vanes, the less loss of contrast there is. Typically a secondary mirror that is 20% of the diameter of the primary mirror is consider to incur minimal contrast loss.