Telescope Calculator shows realistic views of what you will see with different telescopes and eyepieces. The simulated view and several readouts automatically refresh as you change the settings. Click and drag the sliders below to see different simulations. Enjoy!
Telescope and Eyepiece settings
To use the telescope calculator, click on the green slider knobs and drag them to the left or right as desired. You may also type your desired settings directly into the white text fields. You can see what different eyepieces may look like by changing the eyepiece settings.
To change the object being viewed, click the arrow next to the 'Object Data' label and make a selection. To view planets (Mars, Jupiter, Saturn), you must lower the eyepiece focal length (try 9mm) and possibly select the 2X barlow. To view the Pleiades, you will need to select NO Barlow and increase the eyepiece focal length (try 50mm).