Amazing lens, incredible sharpness

c_henry wrote:

Great Bustard wrote:

So it's f1.8 no matter what the sensor size.

It's also 75mm no matter what the sensor size.

So the 75mm is the equivalent of a 150mm f1.8 on FF, except for DoF where you get more.

No. 150mm f/1.8 will also project 4x as much (2 stops more) light on the sensor for a given shutter speed, resulting in half (one stop less) then noise for equally efficient sensors.

Actually, it's yes. We've agreed f1.8 is f1.8 whatever the sensor size.

Not "f1.8" but "f/1.8", where "it" that "we've agreed" upon means the diameter of the aperture (entrance pupil), and the "f" in "f/1.8" means "focal length":  75mm / 1.8 = 150mm / 3.6 = 42mm.

If you want to go off talking about noise then, well, whatever floats your boat, but that's not what I was asking.

Aside from DOF and noise, why would anyone care about the aperture?  And if f/3.6 on FF has the same DOF as f/1.8 on mFT for a given perspective and framing, and f/3.6 on FF puts the same total amount of light on the sensor as f/1.8 on mFT for the same shutter speed, resulting in the same noise for equally efficient sensors, well...

That's good to know. Appreciate the help.

Glad to help! So now you understand that 150mm f/1.8 on FF looks rather different than 75mm f/1.8 on mFT, whereas 150mm f/3.6 on FF looks very similar to 75mm f/1.8 on mFT (for a given shutter speed and sensor efficiency).

Again, not really relevant to my question, but appreciate you taking the time to miss the point.

So, your question has nothing to do with the visual properties of the photo, but rather numbers used out of context?  Apologies!  I did indeed miss that "point".