[G]rain is a matter of taste, some love it, some hate it. I personally love it as I believe that it adds character to cold and mathematical digital photographs. Here is a combination to add just enough grain to to your photographs.
Every photographer have their little rituals that they do, whether it is to rocking the developer tray a certain way, or it is adjusting the white balance a certain way. I have many of those but I would like to share my “Magical grain combination” for Lightroom. These settings are (in the grain area) Amount: 50, Size: 50, Roughness: 50. It's my 50-50-50 grain combination.
Look at this photograph:
On the left there is no grain added and on the right, the 50-50-50. This grain combination is simply magical because it's the perfect balance of grain in my honest opinion. It just adds mood exactly right, not too overwhelming, not too little, just right….the Goldy-lock grain! I find that this combo works even for higher ISOs, provided that the camera is a good one. 50-50-50 makes the photographs more organic and less digital in the simplest way, observe the photograph above, look at the bottom, left, then right. The difference is night and day yet it does not overwhelm the photograph. Here's another one:
Same thing again, on the left is the original grain and on the right, the 50-50-50 combo. A very subtle change but a very definite change that affects the mood of the photograph. Digital is so cold, by using 50-50-50 (tell me that's not already engraved in your head!) you transform it into something more organic. There is no thou shall put your grain at 50-50-50 but it is a simple way to automatically add mood to your photographs, and it's easy to remember….I must also not that when in comes to color grain does not do much…sorry color fans!