Thread: F-ratio myth
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Old 20-02-2018, 10:51 PM
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Slawomir (Suavi)
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Originally Posted by Peter Ward View Post
All you will get is a wider field of view over the same sensor. Unless you increase the aperture you will not be collecting more flux.

Google Stan Moore F ratio myth

I guess then the laws of physics somehow do not apply here, and my direct experience with these two f-ratios with my scope n camera, where I could easily see stronger flux per pixel per unit of time at f/4.5 as opposed to f/6 (confirmed by SNR measurements with PI) are either my imagination or camera n PI are “playing Jedi mind tricks’ does not provide answers to all questions Peter

So if we take a glass window (simulating a very large 1m aperture with loooong focal length), it clearly will be putting photons on a pixel behind the window much more slowly than a 4” strongly converging lens (small aperture fast f-ratio) placed in front of the same pixel.

Let’s create a new myth - “larger aperture is always faster”...

Last edited by Slawomir; 20-02-2018 at 11:03 PM.
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