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Falling out of love with Canon

Started Sep 15, 2019 | Discussions thread
PhotoFactor Veteran Member • Posts: 4,170
Re: Falling out of love with Canon
1

J A C S wrote:

PhotoFactor wrote:

J A C S wrote:

Microprism wrote:

J A C S wrote:

Microprism wrote:

J A C S wrote:

Microprism wrote:

J A C S wrote:

Funny how from f/1.4 we got to f/2.8, which is f/4.2 equivalent...

f/1.4 is f/1.4 is f/1.4 in terms of exposure. There is no equivalency for that.

This is the reason exposure is of limited use when comparing formats.

Come on, this is 2019.

In dim light, shutter speeds are key and what makes maximum aperture such a crucial feature. That doesn't vary across formats, even in in 2019.

Nobody said it did. What makes difference is the maximal physical aperture (for the same FOV). The f-number is a ratio which confuses you.

I don't think I'm confused. For instance, f/1.4 at 1/30 sec @ISO 100 will yield the same exposure in any format. Depth of field and field of view change, but not exposure.

Why would you care about the same exposure?

The lens defines the widest f-stop. That defines what shutter speeds you can use at a given ISO to get a good exposure.

Wrong, the shutter speed is chosen by the photographer, and the "good exposure" is format dependent.

Myth #1 is still alive, I see. You have nine more to go.

Shutter speed is important to not having blurry images. That's why exposure is important. I don't care about my lens element size, I care about my maximum f-stop because that dictates what kind of exposure (ISO/shutter speed combination) I can achieve.

I guess I could calculate the maximum aperture diameter (focal length/widest f-stop) for each of my lenses, and put a label on each of them with this value since that's not printed on the barrel, but that seems kind of pointless and silly since i would never use that information.

You do not have to if you understand equivalence. It is as simple as multiplying by some number.

You can look at it any way you want, as can I. I know the noise characteristics of my format and sensor. I know that say and f2.8 lens will give me a good exposure at 1/125 second. I've chosen say APS-C for size and acceptable noise characteristics for a given ISO. I might let the camera choose my shutter speed,, or I might. If I'm shooing in dim light I might choose to shoot wide open at the highest ISO I want to use commensurate with a shutter speed that I believe will enable no motion blur. And those values will be the same if I had an M43 or a FF camera, too. The noise characteristics would differ due to the format. As would the DOF. I don't really care about the absolute lens diameter - other than its impact on how much size I have to carry.

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