Scale Down By

The simplest of Art Venture's resize trio: pick a fraction, get a smaller image. 0.5 halves both dimensions, 0.25 quarters them, and so on. No target size to compute, no aspect-ratio math - just "make this proportionally smaller by this much." If you already know you want the image at half scale, this is the least fiddly way to say it.

You'll reach for it when the scale factor is the thing you actually care about: shrinking a control image to match a smaller generation, making a quick low-res preview, or dropping a batch to a lighter size before a heavy step. It's the counterpart to ComfyUI's native "Upscale Image By" - same idea, pointed the other direction, and capped so it can only shrink.

How it works

It multiplies width and height by scale_by and resamples down. Because both dimensions get the same multiplier, the aspect ratio is preserved automatically. Downscaling discards pixels rather than inventing them, so there's no quality-guessing involved - the result is a clean, smaller version of the input.

The inputs and outputs that matter

There are only two, which is the appeal:

• images - the image or batch to shrink.
• scale_by - the multiplier, default 0.5, range 0.01–1. It's clamped at 1, so this node genuinely cannot upscale - 1 is a no-op passthrough and anything below shrinks. 0.5 is half size, 0.25 is quarter, 0.1 is a tenth.

Output is a single IMAGE at the scaled size.

When to use this vs the other two

Art Venture ships three downscalers and they answer three different questions:

• ImageScaleDownBy - "shrink by a proportion." You know the factor.
• ImageScaleDownToSize - "cap one side at N pixels." You know the max dimension.
• ImageScaleToMegapixels - "hit a total pixel budget." You know the area you want (usually to match a model's native resolution).

If your goal is "get this to SDXL's ~1MP sweet spot," reach for megapixels. If it's "make it exactly half," this is your node.

How to install it

Part of the Art Venture pack. ComfyUI Manager → search comfyui-art-venture → Install → restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/sipherxyz/comfyui-art-venture

then pip install -r comfyui-art-venture/requirements.txt and restart. No model download.

Common issues & troubleshooting

I set scale_by above 1 and nothing happened. You can't - the input is capped at 1. This node only shrinks. To enlarge, use ComfyUI's native "Upscale Image By" or route through an upscale model.

The result is blurry. At small factors you're throwing away a lot of pixels; some softening is expected, especially on fine text or thin lines. That's inherent to downscaling, not a bug. If you need the small version to stay crisp, sharpen lightly afterward or downscale in gentler steps.

Node missing after importing a workflow. The pack isn't installed. Open Manager → Install Missing Custom Nodes and it'll grab the whole Art Venture set at once.