I say "again", because I snagged a picture of this same car last November...
Now, it's really not fair comparing the two photos directly. They were taken at about the same time of day and with similar lighting conditions, yes, but the older one was taken from further away and cropped out of a shot taken with the long kit zoom on a Nikon 1 J4 at an equivalent focal length of about 270mm.
The next two photos, however, I think are illustrative of differences in sensor size and lens quality. Both were shot with the camera in Program mode, letting it pick aperture and shutter speed.
Here's the one from the 18MP Nikon 1 J4. I'm shooting from across the street at a focal length of 36.1mm which, with the 2.7X crop factor of the 1" sensor, is about a 98mm equivalent. The camera was set at ISO 160, and picked 1/1000th of a second exposure time at f/4.
The Nikon 1 J4 could do some neat tricks, and its 18MP sensor had lots of megapickles for a 1" sensor in 2014. The full resolution images are 5232 x 3488 pixels, and your monitor is probably not set to display that resolution. I know mine isn't.
Yesterday's pic was shot with the Nikon D700 and the 24-120mm f/4 lens at a focal length of 100mm. This camera's 12MP full-frame sensor dates to the middle of 2008. It only has two thirds as many photo sites as the 1 J4, but they're spread over a physical area seven and a half times larger.
This was ISO 400, 1/400th at f/11, and the one takeaway looking at both is that even with a few years development between them, the full frame sensor was less noisy at ISO 400 than the 1" sensor was at its base ISO of 160.
Physical size of the sensor has an effect; there's more to a sensor than its megapickles.
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