Use stable coordinates
Marked positions are stored as percentages of the displayed test area, measured from its upper-left corner. Full screen minimizes browser chrome, but operating-system scaling and zoom can still change the relationship to physical panel pixels. The coordinates locate an observation; they are not a hardware pixel address.
Keep settings reproducible
Record the monitor model, input resolution, refresh rate, HDR state and any processing settings outside the exported pattern notes. If those settings change, repeat the inspection. A screenshot captures the generated image and generally cannot capture a physical panel defect.
Share useful evidence
The CSV lists manually marked positions and the active pattern. Add clear notes and, where appropriate, a photograph taken under controlled viewing conditions. Distinguish suspected dead pixels, uneven backlighting and surface dust; this tool deliberately does not merge those observations into a certified diagnosis.
Keep interactive marks and typed notes distinct
The form accepts observation rows in the documented format and includes them in the generated report. During the display test, Mark positions creates a separate live list. Download that list with Download marks CSV before closing the viewer; the interactive list is not automatically inserted into the earlier report. This distinction prevents an unchanged report from appearing to contain observations made afterward.
A point marked halfway across and one-quarter down the displayed test area is recorded near X = 50 percent and Y = 25 percent. If browser chrome remains visible, those percentages refer to the test area rather than the full physical panel. Record whether full screen was available.
Package evidence that someone else can reproduce
Save the CSV with your display model, connection type, signal resolution, refresh rate and test conditions. Add a carefully focused photograph if a physical defect needs documentation; the browser’s screenshot normally records generated pixels rather than a failing subpixel. Repeat the same pattern at the same location when comparing dates. A manual observation record supports a support conversation, but it does not determine warranty eligibility or certify a panel as defect-free.