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Old 01-06-2019, 04:53 PM
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Slawomir (Suavi)
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Quote:
Originally Posted by FrancoRodriguez View Post
My question is, why do people get the larger setup?
With DSO imaging in mind, these are the reasons that I can think of at the moment, in no particular order:

1. Diffraction. Larger aperture allows to resolve finer details, and seeing rather than aperture become the limiting factor.

2. Larger aperture allows for imaging fainter stars. This does not directly translate to extended objects.

3. Generally high quality astronomical cameras with deep cooling and reliable electronics come with larger pixels, and such larger pixels must be paired up with longer focal length in order to avoid under-sampling. The last point is gradually becoming less significant due to the recent developments in the sensor area.

4. Large aperture with short focal length = speed.

Hope it helps a bit.
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