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Molly,
A short focal length telescope can actually have a longer focal length than a long focal length telecope.
The terms short and long refer to the ratio of the focal length to the aperture diameter.
For example, a refractor with focal length 900mm and aperture lens 90mm has a focal ratio 900/90=10 or f/10.
A reflector with focal length 1500mm and primary mirror 300mm has a focal ratio of 1500/300=5 or f/5.
Focal ratios around f/5 are short while those around f/9 or higher are considered long.
The term fast is also used. A fast telescope implies a short focal length and a wide field of view.
I guess f/7 would be considered short.
Regards, Rob.
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