# Zoom and pan a reference

Pinch, drag and use keyboard controls on original images and PDF pages.

## Choose your control

- Touch: pinch with two fingers to zoom; drag with one finger to pan. Double-tap toggles between 100% and 200%.
- Mouse: drag to pan, double-click to toggle zoom, or use the zoom buttons.
- Trackpad: pinch uses Ctrl+wheel where the browser exposes it; ordinary scrolling pans the sheet.
- Keyboard: focus the reference pane, then press + or - to zoom and 0 to return to 100%.



## Keep the drawing in context

Zoom ranges from 25% to 600%. Pinching changes the reference inside its pane, not the rest of the page. New references start at their default scale. Image pixels cannot reveal detail absent from the original source; use the original PDF or vector companion when available.



## Read a PDF

Page and rotation controls remain available. At high zoom, the viewer limits canvas memory and briefly scales the previous rendering while a sharper page is prepared. Download the original for printing or another PDF reader. Browser-emulated touch is regression-tested; physical touch and Safari behavior can vary.



[Read the public wiki](https://valleytech-black-wire-guide.pages.dev/wiki/reference-viewer/) · [Open the guide](https://valleytech-black-wire-guide.pages.dev/)