Keep one input path and picture mode during each comparison. Inspect pixel-sized points close to the panel, then return to your normal seat for uniformity, blooming, tone, and motion.
Run the page in a TV browser or from a connected computer. Keep the signal path and picture mode unchanged during a comparison, then judge broad artifacts from your normal seat and pixel-sized marks up close.
Fullscreen colors make a fixed point easier to find on a large panel than ordinary video does.
Run it: Approach the screen for a row-by-row scan, then step back to decide whether the observation is visible in normal use.
Look for: Track the same coordinate across black, white, RGB, and grey and check the surface without pressing it.
A TV browser, connected computer, mirroring path, or overscan setting can crop or scale browser patterns.
Run it: Compare the browser viewport in embedded and fullscreen modes, and verify that all pattern edges are visible.
Look for: Cropping or soft edges can come from the signal path and TV scaling rather than the panel itself.
Keep in mind: The Screen API does not prove the TV panel native resolution or input signal format.
Neutral fields expose broad clouding, vertical bands, dirty-screen effect, or tint on backlit televisions.
Run it: Use low and mid-grey from the normal seat, then inspect black at a realistic evening brightness.
Look for: Judge large areas at viewing distance; a camera image can exaggerate dark-field differences.
Bright shapes on black can reveal zone halos, delayed transitions, and subtitle-like blooming on local-dimming LCD TVs.
Run it: Use small static and moving targets with the TV local-dimming mode you normally watch.
Look for: Compare halo size and brightness from your seat; do not infer a physical zone count from the pattern.
OLED televisions need grey retention, near-black, and tint checks instead of an LCD bleed workflow.
Run it: Use this branch only for a confirmed OLED panel and keep high-brightness static fields short.
Look for: Treat faint residual shapes cautiously because temporary retention and permanent aging can look similar.
Grey steps and ramps can reveal clipping, processing contours, or broad vertical structure.
Run it: Keep the same TV picture mode and signal path while moving between step, ramp, and uniform-grey views.
Look for: Browser SDR patterns cannot certify HDR performance, panel bit depth, or calibrated EOTF tracking.
Multiple speed lanes make trails, blur, and motion discontinuities easier to name before focused follow-up.
Run it: Use the picture mode and motion processing you normally watch, then compare with processing changed only if useful.
Look for: Separate sample-and-hold blur, trailing, interpolation artifacts, and browser cadence limits.
Near-black bars and fields help reveal whether adjacent shadow levels remain visually separable.
Run it: Dim ambient light, avoid crushing brightness controls to an extreme, and compare several levels above black.
Look for: This is a visual SDR check, not an exact contrast or black-luminance measurement.
Large-screen inspection
This TV screen test separates close pixel inspection from observations that matter at normal viewing distance. It also accounts for a TV browser or connected-computer signal path, LCD backlights, Mini LED local dimming, OLED-specific behavior, grayscale, and motion processing.
Two distances, two questions
Use black, white, RGB, and grey while standing close enough to scan individual panel coordinates. Do not touch, press, rub, or heat the panel. After finding a suspect point, step back and check whether it affects normal content at the usual seat.
Judge vertical banding, dirty-screen effect, corner brightness, tint, blooming, subtitle halos, shadow separation, and motion from the distance where the television is watched. Broad effects can look different close to a large panel.
Know the signal path
Built-in browsers vary in CSS viewport size, zoom, Fullscreen API support, animation cadence, and color handling. A browser limitation is not automatically a TV panel fault.
The operating system, GPU scaling, output color format, cable path, input label, TV overscan, and picture mode can all affect pattern framing. Confirm that every edge is visible before judging geometry.
Mirroring and casting may rescale, compress, buffer, or limit frame delivery. Use a direct TV browser or direct cable when possible for the cleanest context, but do not assume either path exposes hardware measurements.
Panel branches
A conventional LCD television uses a separate backlight. Black and low-grey fields can expose fixed edge brightness, clouding, vertical structure, or viewing-angle effects. A Mini LED television is still an LCD, but its many local-dimming areas make isolated targets useful for observing halos, delayed zone transitions, or brightness pumping. The browser cannot count those physical areas or establish a universal acceptable halo size.
OLED is self-emissive and has no LCD backlight bleed. Use grey fields for faint persistent images, low grey for near-black behavior, RGB for broad tint, and black for unexpected lit points or raised signal-path blacks. Temporary retention and permanent differential aging require cautious interpretation; this site cannot read the TV’s compensation-cycle status.
A web page can request CSS colors and draw patterns through the browser. It does not know whether the complete path is outputting a particular HDR format, metadata, bit depth, gamut, or transfer function. Use documented TV test procedures and appropriate measurement hardware when those specifications matter. This workflow is for visible symptom triage and repeatable observation.