Image Calibration Targets
Make geometric targets for camera or print experiments using physical dimensions. Set the checkerboard square side, concentric-dot center pitch or line-period progression; the same millimetre coordinates produce both SVG and PDF. DPI calculates the equivalent raster pixel dimensions and does not change the vector artwork. Printer scaling and paper handling can change the physical print, so measure the included 50 mm reference rule afterward.
Key features
- Checkerboard with separately chosen row/column count and square side length
- Three-ring concentric dots with defined center pitch and outer diameter
- Black-and-white line groups with labelled physical periods in millimetres
- Millimetre/inch inputs, A4 or US Letter sheets and DPI-equivalent pixel dimensions
- Printable SVG and PDF from the same geometric coordinates plus a 50 mm measurement rule
How to use
- Choose a checkerboard, concentric-dot grid or line-frequency pattern.
- Set sheet size and margins in millimetres or inches, then edit the pattern-specific dimensions.
- Check the preview and dimension table to ensure the pattern fits the sheet.
- Download SVG or PDF, print at actual size/100%, and turn off fit-to-page scaling.
- Measure the printed 50 mm rule with a physical ruler; adjust printer settings if it is off.
Use cases
- Prepare a square grid for camera intrinsic-calibration experiments
- Create known physical dot-center spacing for feature-detection tests
- Compare how different line periods appear after imaging or scanning
- Check whether a printer silently enlarged or reduced a target
Frequently asked questions
Do SVG and PDF use the same physical dimensions?
Both files use the same millimetre geometry. SVG stores width and height in mm; PDF stores the corresponding lengths in points at 72/25.4 pt per mm. A viewer or printer can still rescale either file, so measure the print.
Does changing DPI alter the SVG or PDF?
No. DPI only estimates the pixel dimensions if the sheet were rasterized. It does not change the vector sheet size or square, dot or line positions.
Will this guarantee an accurate camera calibration?
No. This tool generates the requested print geometry. Printer scaling, paper distortion, lens behavior, capture angle and detection software determine actual calibration quality.
What should I check when printing?
Select actual size or 100% and disable fit-to-page or automatic shrinking. Measure the printed 50 mm line, then adjust print settings or paper if needed.
Privacy
Settings and artwork are generated in your browser without uploading them to a server. This page does not save your input to an account.
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