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Milky Way - 32mm f/1.4 - (PIC).

Started Oct 5, 2018 | Discussions thread
scottfrey
scottfrey Regular Member • Posts: 135
Re: Milky Way

According to my calculations, of the 32mm on the M5's 24MP sensor:

A) Time for a star (at celestial equator) to cross from one pixel to the next: 1.59 seconds

B) Rule of 200 (for high res sensors) Max exposure of 3.91 seconds for no star trailing.

- A) So, if a star is say, 8 pixels in diameter on the sensor (based on brightness and bleed, all stars are actually points) a 15 second exposure would result in an 8 x 15 pixel oval. Pretty unnoticeable without pixel peeping. certainly masked by posting a jpeg to the internet.

- B) a 4 second exposure results in round stars under 4-1 zoom in my testing. You are doing more like the "rule of 600" at 15 seconds, which most people find acceptable, especially at web resolutions. I don't usually, but that is my opinion, not a rule or anything.
I noticed a tiny bit of corner coma at 1.4, seems mostly gone at 2.8. Acceptable at 1.4, and waaaaaaaaaaay better than my Rokinon 24mm at any aperture.

All that said, I'll still use my tracking mount when I can, but this does open up the possibility of getting useful shots when I don't have it.

 scottfrey's gear list:scottfrey's gear list
Canon EOS M5 Canon EOS R6 Canon EOS R10 Canon EF 50mm F1.4 USM Canon EF 70-200mm f/2.8L IS USM +9 more
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