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Moons of Jupiter

The clear evening skies at the moment have provided great views of Jupiter, which is currently well placed for Northern Hemisphere observers.

To get a closer look, I got out my Russian MTO 11CA, which is a 1000mm f10 mirror lens originally built for the Soviet military in the Cold War period. It is built like the proverbial tank and reasonably sharp for such modestly priced lens. I hooked it up to my Panasonic GF-1 via an M42 to micro 4/3 adapter. This gives an equivalent focal length of an enormous 2000mm!

MTO 11CA 1000mm f10 Mirror Lens


Pointing the combo at Jupiter showed a clear view of the four brightest moons:

Jupiter's 4 brightest moons
L-R: Callisto, Ganymede, Jupiter, Io and Europa

Unfortunately, there is no surface detail visible on Jupiter and the whole image is lacking in sharpness. This was mainly due to difficulties in keeping the lens still, as it is a light lens with a long focal length, making it susceptible to the slightest vibration. It doesn't help that the tripod mount is a rather weak and shallow affair and the night air was also not particularly still, due to the very warm weather. Still, amazing what you can see without a telescope...

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