Eliminate scaling first
The TV displays video normally, but small letters on the desktop are blurry or have colored edges. The reason is not necessarily the cable. The appearance of text is affected by native resolution, image magnification, TV processing, signal format and matrix pixel structure.
Check that the computer is outputting the panel's native resolution. In the TV menu, find the display setting without cropping or scaling; names depend on the model. Return the browser page zoom to 100% and remove the magnification with a gesture. If several screens are connected, transfer the entire window to the one you are checking.
Compare brightness and color details
The black and white sample controls overall clarity, while the color sample controls color detail. In the test below, the stripes are drawn directly on the device. Click full screen or download the PNG and open it without resizing.
Chroma subsampling 4:4:4 test
FreeLoading the check...
Look for stripes in both directions. If black and white also merge, it’s too early to draw a conclusion about color subsampling: first, figure out the scale and overall sharpness. If black and white are distinguishable, but color ones are noticeably blurred, this is a reason to check the color path.
What changes between 4:4:4, 4:2:2 and 4:2:0
These notations are about detailing color information. Reducing its resolution may be subtle in regular video, but appear at the fine color boundaries of computer graphics. At 4:2:2, horizontal color detail is reduced, at 4:2:0, vertical color detail is also affected.
The browser does not receive a reliable response from the HDMI cable about the actual format. Based on the picture, we check the result of the entire chain, and the specific RGB or YCbCr value must be checked in the settings of the video card and device.
Change one parameter at a time
- Check the assignment of the TV input: a separate PC mode may be provided for the computer.
- Check the color output format. If your hardware allows it, compare RGB or YCbCr 4:4:4 with the current mode.
- If full color mode is not available at the selected resolution and frequency, temporarily reduce the frequency or other setting that affects the required throughput and repeat the test.
- Then separately check another port or cable that is suitable for the selected mode.
Write down what has changed. Changing the cable, frequency, HDR and picture mode at the same time will not show which step helped. Don't immediately buy a new cable just because the text is blurry.
Why a screenshot might look good
A screenshot can capture an image before transformations at the output of the video card or inside the TV. Therefore, a good screenshot on another device does not exclude the problem on the display being tested. For comparison, look at the screen itself; When photographing outdoors, consider focus, moire, and camera processing.
Matrices with an unusual arrangement of subpixels are also capable of changing the appearance of small letters. Text smoothing and sharpening settings may affect subjective ratings. Therefore, the test saves your observation and does not automatically issue a 4:4:4 certificate.
What to check separately
One fixed point - a task checking for dead pixels. Light spots on a dark background refer to uniformity of illumination. Stripes on a smooth transition of shades are more convenient to watch in the gradient test. These checks are complementary to the color swatch and are not intended to replace each other.