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Telescope aperture comparison

We proudly present you a graphical tool for all astronomy fans. We have produced a graphical tool that shows you different apertures and mirrors sizes of refracting and reflecting telescopes in comparison. This graphical info-sheet is aimed at telescope owners and potential telescope buyers, to serve as a simple guide to light gathering power of different types/sizes of telescopes. This is a hobby-group specific product, so some basic knowledge of telescopes is recommended/required.

Since there is usually a lot of talk about telescope aperture sizes and how much light gathering power they have, we decided to do a proper graphic, such that contains basic information on most common aperture sizes and their light gathering area, for refactors and the small to medium reflectors. We also removed the secondary mirror obstruction areas, so the reflector mirrors have provided the actual light gathering area, calculated from the light exposed surface only (subtracted secondary obstruction). For the dimensions of the mirrors, we took the Synta mirror specifications, with their smallest corresponding secondary mirrors. The 6″, 8″ and 10″ inch mirrors have the same dimensions of the secondary mirrors across different brands, but there were some minor secondary mirror size differences between 12″ and 14″ reflectors (between Orion and SkyWatcher brands).

The shapes are precise and drawn with CAD tools. We made this as a reference point for beginners and experienced telescope buyers, to get an idea on what the light gathering capacity is, as we increase the aperture/size of the telescope, compared to the human eye and other telescopes.

Click on the image for larger resolution.