⚙️ CR Select ISO Size

This one's for anyone building toward a printed output - a poster, a card, a commission that needs to leave the screen and go to a printer. CR Select ISO Size is a dropdown of the standard ISO 216 paper sizes (A4, A3, and the rest of the A-series, 36 entries total) that hands you back the pixel dimensions for that page at print resolution, instead of you looking up mm-to-pixel conversions yourself.

Do the math on one entry and it checks out exactly: A4 is 210x297mm, which at 300 DPI (the standard print resolution) comes to almost precisely 2480x3508 pixels - the exact number the node's A4 option lists. So this isn't an approximation, it's a real print-ready lookup table.

How it works

Pick a size from iso_size - the list runs the A-series from A0 (the biggest, 9933x14043) down through the smaller sizes - and the node outputs the matching width and height in pixels at that print resolution. That's the entire node: one dropdown, two number outputs.

The inputs and outputs that matter

• iso_size - the paper size dropdown. This is the whole input.

Outputs: width and height (INT), plus the standard show_help link.

How to install it

Comfyroll Studio (Suzie1 and RockOfFire), no models or heavy dependencies.

• ComfyUI Manager - search "Comfyroll Studio," install, restart.
• Manual - cd ComfyUI/custom_nodes && git clone https://github.com/Suzie1/ComfyUI_Comfyroll_CustomNodes.git, then restart.

Common issues & troubleshooting

Don't generate directly at these dimensions. A4 at 300 DPI is 2480x3508 pixels - nowhere near what an SD 1.5 (512-native) or even SDXL (1024-native) checkpoint was trained to produce in one pass. Feed those numbers straight into an Empty Latent Image and you'll either run out of VRAM or get the classic duplicated-subject mess from generating way outside the model's trained resolution. The real workflow is: generate at your model's native resolution, then upscale to this node's output size for the final print export.

No latent output, unlike the aspect-ratio nodes. This node only gives you width/height as plain integers - you wire those into an Empty Latent Image or an upscale node's target-size inputs by hand. It's a size lookup, not a full pipeline node like CR SD1.5 Aspect Ratio or CR SDXL Aspect Ratio, which bundle a ready latent.

A size you expected isn't in the list. The dropdown covers the ISO 216 A-series; if you need a photo print size (4x6, 8x10) or a social-media aspect ratio instead, that's a different Comfyroll node's job (CR Aspect Ratio Social Media, CR Aspect Ratio For Print) - this one is specifically the paper-format series.

Comfyroll nodes missing entirely. If the whole pack fails to load, check your startup log for Comfyroll Studio: Failed to load Graphics nodes and a trailing NameError: name 'CR_HalftoneGrid' is not defined - a symptom of an earlier import error, commonly a Pillow version conflict from another custom node. Force-reinstall Pillow (pip install --upgrade --force-reinstall pillow) or reinstall the pack cleanly, then restart.