Grain and Noise

In photography, grain and noise are visual artifacts that result from how the image is captured/processed, grain refers to the optical effect caused by particles of silver halide crystals that form during the development of analog (film) photographs, color film grain also has dye clouds (not just silver crystals)

These crystals are light-sensitive and have a response curve to them. They vary in size and distribution depending on the shooting medium (film stock) used. Larger crystals lead to coarser grains, and smaller ones lead to softer grains.

Having said that, some people see grain as a desirable feature of photos while others see it as a problem that detracts from the image quality. However, grain is present in a lot of works, is almost unavoidable when shooting analog film, and can also sometimes be added to digital works to achieve a film-like look.

Grain in analog can vary based on light and dark parts in the image. Usually, there is almost no visible grain in bright spots, because the silver crystals are fully exposed to light, and there is less visible grain in black parts of the image, because there isn't enough light to illuminate the particles there, so grain is more prominent in the shades and tints of the image.

However, dark and light parts of the image can still have visible grain if the film is pushed or developed aggressively because that amplifies the signal in those areas, making the grain visible to the naked eye (same with editing the image in software).

Also, something of note is the trade-off of film speed (light sensitivity, also known as the film stocks ISO which is pre-determined by the manufacturer) and crystal size. So the bigger the crystals, the more chances it receives enough light to go into a developable state. This means that large crystals result in more sensitive film but at the expense of being visibly grainier and less detailed, while smaller crystals (finer grain) are better at preserving detail but require more light.

On the other hand, noise in photography refers to random variations of color information/brightness in digital camera photography, more so under low light, high ISO, long exposure times, and heat.

Noise is often colored, which can come in random RGB dots and/or luminance-altered dots, which are often undesired in photography. The noise pattern depends on the sensor, with cheap sensors that may show banding or fixed pattern noise, and higher-end sensors which tend to have more random noise (closer to film grain).

It also can be removed with denoising software without altering the overall look of the image much, but removing grain from analog-based media is often invasive and involves altering the overall film look. Although some photographers intentionally reduce grain for a cleaner scan.

Grain Vs Noise

Grain	Noise
Film Cameras	Digital cameras
Organic, textured	Pixel-level, harsh
Random-sized particles	Random or patterned dots
Monochromatic or colored	Usually colored (RGB dots)
Artistic/Vintage	Generally undesirable

Why Film Grain?

There are a lot of reasons to use grain, for example, you could use grain to fake detail on low LOD objects in some games, or try to reduce banding in the image. More uses for grain include mimicking the film look found in movies, or adding that layer of realism to a shot like it was taken from a real camera.

Here's a quick comparison of grain vs no grain, you can see the difference in how the overall image feels much less plastic-looking:

Here's another example from Mass Effect: Andromeda:

You can see the mountains to the right appear to have detail to them. Here's a zoomed-in comparison with the vanilla shot:

How to add it to pictures

There are multiple ways to implement film grain into your pictures, we however recommend using Reshade as the best way to implement it:

• Shaderdeck by TreyM. (free version also available inside Reshades setup).
• PD8006_Film_Grain.fx by prod80, within the shader pack called "Color effects by prod80" in Reshades setup.
• MartysModsFILMGRAIN.fx by Marty McFly. Also available in Reshades setup.

However if for any reason you cannot use Reshade to add this, there are other ways to mimic grain:

• Lightroom can actually mimic grain, however, you'd have to mask the highlights, midtones, and shadows of the image and adjust grain manually for each. This can be tedious if you have a bunch of images to work on, though there is a paid preset which should make this process easier.
• Photoshop with the Exposure plugin. Exposure has a lot of film-like settings and presets which can serve as a starting point for custom edits. The plugin's grain implementation lets you adjust the shadows, highlights, and midtones of the grain without extra work which is super convenient.
• You could also use free image manipulation software alternatives like Gimp. After you install it from the official website, drag and drop your desired image inside the editor, go to Filters/Noise then select the type of Noise you want to add. I recommend using HSV Noise, change dulling to 8 and saturation to 0, and play around with the value until you settle on something that looks right according to the guidelines in the first section. Also, try playing around with other noise types and values.

How much grain do I apply?

This depends on your understanding of grain in film photography. For example, images that appear to be taken at a higher ISO (film speed) should have coarser and bigger grains, while images that are lower in ISO (film speed) should have finer grains.

This is just one of the aspects you should consider when attempting to replicate real grain in an image. We'd suggest reading more into the first section of the guide to better understand how much or how little to apply if you haven't already.

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Written by: NotRay_st

Last updated on: 2025/6/30