Advantages of lower resolution sensor

[ken1921]

Hi

I often notice in camera comparison reviews under 'advantages of the lower resolution camera' comments such as..

Fujifilm X100S advantages over Fujifilm X100F

BIGGER PIXELS ~ 4.82 vs 3.93 MICRONS

Better low-light and dynamic range (all else equal)

So is this generally true of lower resolution sensors and is the lower light advantage significant?

 

Many thanks

[Doug Pardee]

That belief has been pretty thoroughly debunked over the years, but some people just won't let go. Yes, on a per-pixel basis, there will be less noise with larger pixels. But on a per-square-cm basis, the noise is the same. [It might have been true in ye olden dayes before microlenses became standard on sensors, because of the big gaps between pixels.]

However, that is assuming that the entire sensor is always being read. If you're doing video and the camera is using line-skipping, then you won't have the in-between lines to help smooth out the noise. There's no real advantage to having more pixels than you're going to record, and that's often the case for video.

Also, phase-detect AF cannot be averaged over multiple pixels, because it's specifically looking for differences between neighboring pixels. So you'll get better low-light PDAF performance with larger pixels, albeit with reduced precision.

[bergat]

Yes but a  sensor Aps-c of 52 mixel is lower resolution or not?

Edited March 19, 2019 by bergat

[rickmayberry]

Resolution really only has to do with the number of megapixels accessed by the camera's operating system. The size of the sensor plays a key role in the quantity and quality of the light captured. A full-frame sensor with 24 megapixels will have a noticeably enhanced image compared to that of an APS-C or m4/3 sensor, as each pixel on the full-frame sensor is capable of capturing more information from the scene due to a larger surface area. Likewise, a 16 megapixel APS-C sensor will have larger pixels than a same-sized sensor with 24 megapixels, allowing for the capture of more light at each pixel location, allowing for a potentially greater dynamic range -  at the expense of fine detail (resolution). Various hardware improvements, such as backside illumination (BSI), have helped to offset the loss of pixel surface area regarding low-light performance in some cameras, and the ever increasing onslaught of software solutions have helped to reduce or eliminate the advantages of the lower resolution sensors in low-light settings. I can't say that my X-T2 suffers in comparison with my X-E2S regarding light performance, and the resolution is decidedly better with the 24 megapixels of the X-T2 compared to the 16 of the X-E2S. The sensor processing engine in the case of the X100S vs. the X100F (EXR II vs. X-Processor Pro, respectively) will more than compensate for the pixel size difference, I'm thinking.