2. AdobeRGB & sRGB ring chart

The charts below were created to test the ability of a system to display small changes in brightness of colours towards the edges of sRGB and AdobeRGB colour spaces. To work properly this webpage MUST be viewed in a colour manged web-browser. Use the button above the chart to swap between charts created in sRGB and AdobeRGB colour spaces. If the colours remain absolutely identical, when swapping between charts, the browser is not colour managed. Try another browser or, download the charts, (Right click > Save Image As...) and view directly in a colour managed image editor.

The grey scale at the bottom of the chart should look neutral and the two rows of very slightly lighter grey squares should be just visible all the way across the scale. If they are not, your display's brightness, contrast and white point may need adjusting / calibrating, or your display profile may be set incorrectly.

Looking at the sRGB test chart first. This is the least demanding test. The spectrum coloured "donut" increases in brightness from 80% at the inner edge, to 100% at the outer edge. The nine concentric circles drawn on the donut are about 10% darker than the local background colour. The outermost circle is closest to the edge of sRGB colour space. You should see nine complete circles. If there are any areas where the circular lines disappear, then your current setup (dispaly + applied profile) is clipping some of the colours towards the edges of sRGB colour space. Most systems should be able to display the majority of sRGB colour space so it is likely that your display requires adjusting / calibrating or the display profile is incorrect.

If the sRGB chart looks OK, swap to the AdobeRGB chart. This is a more demanding test which will reveal if the system can display small changes in brightness of colours towards the edges of the larger AdobeRGB colour space. The more complete concentric circles that are visible, the better.

If you can see nine complete concentric circles on the AdobeRGB chart, your system is able to display small changes in the brightness of colours at the edges of AdobeRGB colour space without clipping. If your system is used to edit photos, you can work in sRGB or AdobeRGB colour space without problems. If you want the best colour accuracy it may also be worth calibrating your system, if you haven't already.

If there are any areas in the outer circles where the line disappears, then your current setup (display + applied profile) is "clipping" some of the colours towards the edges of AdobeRGB colour space.

Technical notes

The two charts contain identical image data in RGB colour space. The data includes values that extend right to the outer edges (R, G or B = 255) of that space. The image data is then tagged with an sRGB or AdobedRGB profile so the system can decode and display the image data accordingly.

This test does not prove that the a system is displaying accurate colours (a colour calibration device is required for that). It simply checks that a system is able to display a wide range of intense colours, without clipping, at the edges of AdobeRGB and sRGB colour spaces. This relies on having a correctly adjusted display (brightness/contrast etc.) and an appropriate display profile.

A few of the colours used in the charts may lie outside the range of colours that occur in nature. However, with the increasing us of wide-gamut displays and a trend towards producing graphics and images with boosted colour and saturation, the ablility of a system to display such colours without clipping is important.

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