P-Image Upscale

P-Image Upscale is the Pruna node for when your image needs to be big and you'd rather not babysit a local upscaler. You feed it an IMAGE, and it returns a larger IMAGE - and unlike a dumb resize, it's a learned upscaler that invents detail rather than blurring pixels. The KB's upscaling essay makes the case for why this matters: upscaling is where a lot of local workflows either produce mush or require a careful tile-based pipeline. This node hands you the tile pipeline in a box, running on Pruna's cloud.

The two levers you get are the interesting part, because they cover the two different jobs an upscaler can do. upscaleFactor doubles width and height per step. targetMegapixels instead says "I want output around this many megapixels" and lets the model figure out the factor. Different mental models, same output quality.

What you actually set

• image - required, an IMAGE socket. The source to upscale.
• upscaleFactor - gated toggle, default 2 when enabled. A value of 2 doubles width and height (4x the pixels).
• targetMegapixels - gated toggle, default 1, capped at 128 MP. The alternative to factor-based scaling: pick the target size, let the model choose the rest.
• settings.enhanceDetails - sharpens fine textures. The tooltip is honest: may increase contrast and introduce small deviations from the original.
• settings.realism - improves realism, may deviate more from the original, recommended for AI-generated images. That last bit is the practical tip - AI images often have that smooth, waxy look that a realism pass fixes.
• outputFormat - JPG, PNG, WEBP.

Output: one image socket, type IMAGE. Wire it into Save Image and you're done - the upscaled file lands in your output folder.

Install

One-time pack install: ComfyUI Manager → search Runware → install → restart, or

cd ComfyUI/custom_nodes
git clone https://github.com/Runware/ComfyUI-Runware
pip install -r ComfyUI-Runware/requirements.txt

API key into ComfyUI Settings → Runware API key or RUNWARE_API_KEY. Light dependencies, no model downloads.

Where people get burned

• The gated toggles are off by default. upscaleFactor and targetMegapixels are both gated - you have to enable the toggle before the value field does anything. New users stare at the defaults and wonder why nothing scaled. Flip the switch.
• Realism and enhanceDetails change the image. They're not free passes; they trade fidelity for perceived quality. On a clean photo you may not want either. On AI art, realism is usually a win.
• 128 MP is a big file. The cap exists for a reason; upscaling to it produces enormous PNGs that are slow to save and share.
• It's a paid run. Per-run cost prints on the title bar. A 4x upscale is a small bill, but batch-upscaling a folder adds up.

The takeaway: if you've got a local upscaler that works, you probably don't need this. If you don't want to set one up, or you're upscaling AI output and want the realism pass, this node is the shortest path to a big, clean image.