Why angle changes what you see

When a card is photographed from one side, the nearest edge appears larger and the opposite edge appears smaller. A rectangular card can look trapezoidal, and borders that are physically similar can appear uneven. Measuring centering directly from that uncorrected image would mix the card’s geometry with the camera angle.

This is why a useful capture starts with coverage, stability and a confidently detected rectangle. Best Grading Tools uses the iPhone to find the card boundary and rectify perspective locally before selected frames are uploaded. Rectification makes the evidence easier to compare; it does not restore information that blur, glare or a cropped corner has removed.

A better setup for repeatability

Place the card flat on a dark matte surface and keep all four corners visible. Hold the phone above the card rather than from the side. Move slowly until the guide is stable, then tilt the card during the instructed light phase instead of rotating the phone unpredictably.

The goal is not a studio-perfect image. It is a repeatable image in which borders, corners and surface evidence can be traced to a known capture phase. If the rectangle confidence is low or a border leaves the frame, recapture is more honest than a precise-looking number based on weak input.

Centering is one part of condition

Centering describes how the printed design sits within the physical card. It is not the same as edge wear, corner damage or surface condition. A BGT report therefore keeps centering as its own subgrade and shows the evidence beside the overall conservative estimate.

The result remains a visual estimate from submitted images. It is not a physical measurement, an authenticity decision or a promise that an independent grader will assign the same grade.