Finding Tube Length Of A Telescope

Randall Edwards

Finding Tube Length Of A Telescope. Focal Length – The distance between the primary lens and the focus point in a telescope. Generally, the longer the focal length the more magnification and focus a scope will have.

Finding Tube Length Of A Telescope
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Finding the tube length of a telescope is an important calculation when creating a telescope. Tube length determines the focal length of a telescope, which affects the magnification and resolution of the telescope. Understanding how to calculate the tube length is necessary for any astronomer or astrophotographer.

The formula for calculating a telescope’s tube length is fairly simple. To calculate the tube length, you need to divide the focal length by the telescope’s focal ratio. The focal length is the distance from the primary mirror to the point at which the light converges, and the focal ratio is the focal length divided by the aperture. The aperture is the diameter of the telescope’s primary mirror or lens.

Step-by-Step Guide to Finding Tube Length

  • Determine the focal length and aperture of the telescope.
  • Calculate the focal ratio by dividing the focal length by the aperture.
  • Divide the focal length by the focal ratio.
  • The result is the tube length of the telescope.

It’s important to note that the tube length is not the same as the overall length of the telescope. The tube length is only the length of the optical tube, and does not include the length of the mount, tripod, or other components of the telescope. The overall length of the telescope will be determined by the length of the mount and any additional accessories.

It’s also important to note that the tube length of a telescope will change depending on the scope’s location and orientation. This is because the focal length of a telescope is dependent on the telescope’s angle of view. If the telescope is pointing at a steep angle, the focal length will be longer, and the tube length will increase. Conversely, if the telescope is pointing at a shallow angle, the focal length will be shorter, and the tube length will decrease.

In conclusion, finding the tube length of a telescope is an important calculation for any astronomer or astrophotographer. The formula for calculating the tube length is fairly simple, and understanding the formula is necessary for anyone who wants to build a telescope. It’s important to note that the tube length is not the same as the overall length of the telescope, and that the tube length will change depending on the scope’s location and orientation.

Telescope Focal Length Explained

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Getting thrown off by the negative sign of the 2nd lens, not sure where the focal point is. If the focal point of the 2nd lens is to the right of the second lens, which is what the., Finding Tube Length Of A Telescope.


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