Blur

Blur does what the name says - a Gaussian-style softening pass - but it's worth knowing it works on both images and masks, which is the actual reason it's in a mask-focused pack rather than a generic image utility one. Blurring an image gives you the usual softening effect. Blurring a mask is the more common use in practice: it turns a hard, jagged mask edge into a smooth gradient, which is exactly what you want before compositing something back in without a visible seam.

That second use case is worth dwelling on, because it's the single most common fix for "my pasted region has an obvious hard edge." Feathering a mask before it goes into Combine Masks, Mix Images By Mask, Paste By Mask, or a sampler's masked-inpainting input is standard practice across essentially every masking workflow, and this node is the pack's way to do it without leaving Masquerade Nodes for a general-purpose blur node.

The inputs that matter

• image - the image or mask to blur.
• radius (INT, 0–48, default 10) - how far the blur reaches, in pixels. This is the main dial: small values (2–6) give a light feather good for softening a crop edge before pasting; larger values give a much softer, more diffuse falloff.
• sigma_factor (FLOAT, 0.01–3, default 1) - controls how quickly the blur falls off within that radius. The pack's own tip is straightforward: you can usually just leave this at 1 and adjust radius instead. It's there for the cases where you want a specific falloff curve rather than the default, but it's not the knob most people need to touch.

Output is the resulting blurred image or mask, same type as what went in.

Installing it

Blur is part of Masquerade Nodes. Install via ComfyUI Manager (search "Masquerade Nodes") or manually: cd ComfyUI/custom_nodes && git clone https://github.com/BadCafeCode/masquerade-nodes-comfyui, then restart ComfyUI. No models, no extra pip dependencies - a blur kernel is standard array math and needs nothing beyond what ComfyUI already has installed.

Common issues

If a masked paste still shows a visible seam after running the mask through Blur, check that you're blurring the mask that actually gets used for the final composite, not an earlier copy from before some other operation (Combine Masks with round_result on, for instance, will snap a soft blurred mask right back to hard 0/1 values, undoing the feather). Order matters: blur after your last thresholding step, not before it. If the effect looks too subtle to matter, push radius up before touching sigma_factor - radius is doing most of the visible work, and the default sigma_factor of 1 is fine for the overwhelming majority of cases.