Amazing lens, incredible sharpness

Great Bustard wrote:

David Kieltyka wrote:

Just to note...the lens doesn't give a rat's dupa what the characteristics are of the sensor or film frame it's mounted in front of.

Correct. But the visual properties of the resulting photo sure as heck do.

No argument.

If the ratio of focal length to max. aperture diaphragm size is 1.8:1 then the lens is a 1.8. Period (allowing for manufacturing tolerances and lens maker rounding/exaggerating).

Except what does that have to do with the visual properties of the resulting photo?

Geez, it has to do with the properties of the lens. You know...the subject of my post.

It's certainly a good thing to know that larger photosites tend to be more efficient both at photon collection and in turning those photons into legit image-generating electrons.

Except that's not true, as the D600 vs D800 clearly demonstrates.

I did say "tend to be." There are no absolutes in this stuff.

It's also a good thing to know that using a larger sensor/film frame yields less DOF for a particular field-of-view & f-ratio compared to a smaller sensor/film frame.

And perspective and display size. But the same DOF for the same perspective, framing, aperture (entrance pupil) diameter, and display size.

No argument here either...but when taking photographs I don't care about the entrance pupil diameter. I care about the f-ratio.

You know how they compute the f-ratio for a lens, right? They take the quotient of the focal length and aperture diameter. For example, the max aperture diameter for the 75 / 1.8 is 42mm, so the computed f-ratio is 75mm / 42mm = 1.8.

Doesn't "ratio of focal length to max. aperture diaphragm size" (see above) cover this?

(Whether or not this second feature is an advantage or disadvantage is up to the individual photographer.) But when taking photos with an m43 camera/lens combo it's also irrelevant. The format is what it is...you go with it and work within its boundaries, same as any other format including 35mm.

Sure. But when comparing different formats, it sure helps to understand the meaning of the numbers and how they relate to the visual properties of the photo.

A shame the original poster even mentioned the dreaded 35mm format "equivalent." More info is a good thing. But so is less pedantry.

Over and most emphatically out.

-Dave-