What’s that noise?
Photographers have always obsessed about getting technically perfect images. Many factors contribute to this, including lens sharpness, correct focusing and setting the optimum exposure. Those who shoot film also prize fine-grained emulsions that are capable of recording the maximum detail. In the digital sphere, the closest equivalent is image noise, but while it's one of the topics that photographers worry about the most, it's also widely misunderstood.
In this article I'll be explaining the real sources of noise in your image files, and looking at the relationship with sensor size, pixel count and ISO sensitivity. In particular, in the light of the current buzz around full-frame cameras, I'll be exploring whether it's really true that cameras with larger sensors always give better results.
I'll be illustrating my findings with comparison images taken using cameras with four different sensor sizes but similar pixel counts. For full frame, I'll be using the 24MP Sony Alpha 7 II; for APS-C, the 24MP Canon EOS M50; for Micro Four Thirds, the 20MP Panasonic Lumix G9; and for 1in type, the 20MP Canon PowerShot G7 X Mark II. On the whole, these particular models haven't been selected for any special reason
