06-16-2016, 10:26 PM
Quote:Of course not. Similar exposure times are achieved by exposing the same way, i.e., same iso, same f-stop, same shutter speed or exposure time. there is no such thing in this equation as an "equivalent iso setting", only the same iso setting - provided the manufacturer follows teh standardized rules for is. Note that even with film those could and were manipulated to some degree. Not every 100 iso film was created the same, not every sensor base iso 100 is the same either.Of course not. Similar exposure times can be reached in a multitude of ways. Stating otherwise is just nonsense, to be frank. You do not seem to try and understand what is actually written.
I think you may not realize that there is a significant difference between total amount of light captured, and what you call iso equivalence. Obviously, a sensor that is 4x smaller than another, will capture 4x less total light than the other one, but iso, and related aperture and exposure times are still the same.
As to noise levels: funnily enough you do not need the same pixel count per sensor, all you need is a similar technology sensor to reach the same noise level, at the same amount of total photons captured, and even then only when an image is displayed or printed at the same size. This is why a 4/3 sensor is approximately 4 times noisier than a FF sensor, it just captures 4 times less total light for that same image surface area. And this is where the confusion with "iso equivalence" comes in, as the total amount of light can be made equal, namely by selecting a 4x slower iso for a 4/3 sensor (as compared to a FF sensor). IOW, noise is a function of total amount of light captured for a given surface area and magnification, while iso is a measurement for sensitivity, whether artificial or not.
To be very honest, IMO I think it is a moot point. Quality of sensors is at an extremly high level, much more so than film ever was, even with a 4/3 sensor.
Kind regards, Wim
When talking about equivalency:
Equivalent focal lengths are not the same focal lengths. They merely are focal length which result in the same FOV.
Equivalent f-stops are not the same f-stops. They merely represent the same apparent aperture diameter, resulting in the same DOF.
Equivalent ISO settings are not the same ISO settings, nor are they the same number of photons per square mile/kilometer/inch or mm. They merely are ISO settings resulting in the same exposure time. As a side product, if sensors are from the same generation, using similar technology, one will have similar image noise.
That you in your own mind have fabricated a different idea of what "equivalent ISO setting" should mean, is your own business. But don't try to patronise me or others with that nonsense, when we are not wrong.