Glow Node

Glow is the standard tool to create a bloom on bright areas. The principle: blur the image, overexpose it, mix it back with the original. Bright pixels turn into halos.

It offers 8 different filters (Box, Bartlett, Multi-box, Gaussian, Fast Gaussian, Blend, Hilight, Solarize) that change the nature of the halo. For a softer, more natural look, see Soft Glow.

• Effects Library: Tools > Blur > Glow
• Quick add: right-click in the Node Editor → Add Tool > Blur > Glow

• Input (orange) - required. The source 2D image.
• Effect Mask (blue) - optional. A standard mask applied after processing. Limits where the glow shows up in the final render.
• Glow Mask (white) - optional. Specific to this node. A mask applied before processing: only the pixels inside the mask contribute to the glow, but the resulting halo can spread past the mask edges. Ideal to make a keyed object radiate beyond its silhouette.

MediaIn → Glow → Merge 2D → Saver

To isolate the glow to a specific element: a polygon mask on the subject → connected to the Glow Mask (not the Effect Mask, otherwise the halo is cut off at the edge).

Box

Fast, low quality. Square halo edges visible at large radii.

Bartlett

A soft filter with a more gradual falloff than Box. Slower, but better looking on large radii.

Multi-box

Several Box passes approaching a Gaussian. A good quality/speed balance, no ringing artifacts. Num Passes sets the balance.

Gaussian

A soft, symmetrical halo, maximum quality. Slower on large radii.

Fast Gaussian (default)

Constant render time, quality very close to Gaussian. The default choice.

Blend

A non-linear blur that ensures equal visibility in whites and blacks. Useful for a glow on dark areas (smoke, clouds).

Hilight

No halo around the pixels. Odd at first, but very useful for a naturalistic glow where you do not want any visible spill - just a boost of the highlights.

Solarize

A glow with a solarization effect (partial color inversion in the processed areas). A psychedelic/arty look.

Filter

Menu to select the filter (see above).

Glow Size

Size of the halo. Higher = wider halo.

Glow

Strength of the halo. High values risk overexposure - use Apply Mode = Merge to keep it under control.

Blend

Percentage of the glow mixed with the original. 0% = original image without glow, 100% = glow fully visible.

Lock X/Y

Links horizontal and vertical. Unchecked = asymmetric glows (streaking effect).

Color Channels (R / G / B / A)

Turns the glow on or off per channel. For example, you can make only the red glow for a reddish glow effect.

Num Passes (Multi-box only)

Number of Box passes. Higher = smoother but slower.

Clipping Mode

Frame / Domain / None (standard behavior).

Color Scale (RGBA)

Tints the glow per channel. Red scale = 2 + green scale = 1 → a red-tinted halo without touching the original image.

Controls how the halo is blended with the source image.

Normal (default)

A classic additive overlay. The glow is added on top of the original image.

Merge Under

The glow goes under the image, based on the alpha. Useful to keep the object silhouette sharp with the glow spilling around it.

Threshold

Enables two sliders (high/low) that clip the effect to a specific range of values. Equivalent to a brightness threshold.

Glow

A "harder", more contrasted result. Ideal for bold effects: neon lights, fake lens flares, sparkles. More filter and Apply Mode options.

Soft Glow

A softer, more natural result with more advanced gamma processing. Ideal for skin tones, atmospheres and dreamy looks. Fewer options but more subtle.

• Neon lights / signs - moderate Glow Size + high Threshold (through Apply Mode Threshold or upstream) = a clean halo around the neon lights without touching the rest.
• Fake lens flare - strong Glow + Solarize or Hilight filter for an anamorphic look.
• Sparkles - Glow on the white pixels of a noise = radiating sparkles.
• Halo around a logo - logo mask → Glow Mask. The halo spills around the logo but nowhere else.
• Cinematic effect on highlights - Apply Mode Merge Under + moderate Glow = a halo around bright areas without crushing the details.
• Specific glow tint - Color Scale R = 2, G = 0.5, B = 0 → an orange halo even if the source image is white.

• Glow Mask rather than Effect Mask for an effect that radiates beyond the silhouette. That is the fundamental difference between the two mask inputs.
• High Threshold = naturalistic glow - only the highlights contribute. Without it, the halo drowns the image.
• Watch out for overexposure - high Glow + Blend 100% can blow out the highlights. Prefer a moderate Glow + Blend 60-80%.
• The Hilight filter is underused but excellent for a subtle boost without a visible halo.
• For a dreamy effect or on skin, try Soft Glow instead - it is softer.
• Animate Glow to pulse a neon light or a screen: animating Glow (strength) rather than Glow Size gives a smoother result.