Low Light: MFT + f/1.8 vs FF + f/3.0

[anthony5429]

Assuming sensor technologies, electronics, etc are held constant, which sensor/lens-aperture combo below would probably perform better in low-light conditions?

MFT + f/1.8 or FF + f/3.0

The full-frame sensor is larger than the MFT sensor, but f/1.8 is wider than f/3.0. Is there an equation maybe for figuring out how much light is captured?

 

[Propsguy]

What do you mean by "perform better in low light"?... Are you asking which would have a better S/N ratio or which exposure would be more accurate in a given amount of time?

It doesn't do much good to assume that the sensor technologies etc.... can be held constant when asking a question about a real world scenario. The pixel densities of the sensors would be dramatically different if the sensor resolution is comparable, the depth of field would be dramatically different between the sensors, etc, etc.... The ability of the sensor to turn photons into electrons depends entirely on the elements of the question that you want to ignore.

In general, large sensors with low pixel densities produce the best S/N ratio.

Here's an article (not mine and I have no affiliation) that may shed some insight on some of the topics that pertain to your question.

Clarkvision: Digital Camera Sensor Performance Summary

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