Here is a straight forward comparison of the different aesthetics of film grain emulation using VSCO Film's Ilford HP5+ preset using Lightroom's grain simulation vs the grain in Google Nik Silver Efex Pro 2. We also provided an example of the full film and grain simulation created by DXO Film Pack 5. Below are a couple of examples to have a look at.
The image above was taken with a Leica M 240 sporting a Leica Summarit-M 35mm f/2.5 lens. The colour image at the end is the original raw file with standard Lightroom settings. As you can see, the overall effect of the grain simulation between Lightroom and Silver Efex Pro is subtle at full size above, but if you look deeper, you can see just how much more accurate it is as a film grain simulation.
Lightroom tends to just add grain everywhere without trying to simulate how film actually works whereas Silver Efex Pro does. Not only that, Lightroom's "grain size" actually blurs the image depending on the setting! I've never understood this and frankly, the grain simulation in Lightroom leaves a lot to be desired, short of shooting actual film anyway.
Silver Efex Pro simulates the different levels of grain seen at different densities. Above you can see that most of the effect of the grain is in the mid-tones and tapers off in intensity as the image gets brighter and darker. It's not as noticeable at full size, but it keeps the image sharp while actually simulating film grain accurately.
What do you think? Write a comment below. Is the difference important? Does anyone care?
One might say, just shoot film if you want real grain!