I put together this test of the new iPad screen at 50% brightness to show you how the issue presents for me. It's very noticeable in Mail, Safari, iBooks, Notepad, etc., whenever it's necessary to read dark text against a light background. It's not noticeable for video or highly color saturated image viewing. I make no representation that this test is scientifically rigorous, so take it for what it's worth, YMMV.
The image is one single photo of the screen displaying an all white page. The photo was shot in RAW camera format, no flash and with ambient lighting, and not white balanced or other wise adjusted. I used the WB loop in my photo editing suite to zoom in on a small portion of the top right and bottom left corners of the screen and took screen shots. I placed the screen captures side-by-side for comparison.These are the boxes labeled 'pick a target neutral'.
Next I used the color sampler in my photo editor to sample the color in each location. I placed the screen captures above and below for this comparison. The results are displayed in the 'Color Picker (Foreground Color)' box. The top image shows the results for the bottom left corner of the screen (6c6766) and the bottom image shows the results for the top right corner of the screen (646a64). I think it's pretty clear that the screen has different color tints (green in the upper right corner, pink elsewhere).
The image is one single photo of the screen displaying an all white page. The photo was shot in RAW camera format, no flash and with ambient lighting, and not white balanced or other wise adjusted. I used the WB loop in my photo editing suite to zoom in on a small portion of the top right and bottom left corners of the screen and took screen shots. I placed the screen captures side-by-side for comparison.These are the boxes labeled 'pick a target neutral'.
Next I used the color sampler in my photo editor to sample the color in each location. I placed the screen captures above and below for this comparison. The results are displayed in the 'Color Picker (Foreground Color)' box. The top image shows the results for the bottom left corner of the screen (6c6766) and the bottom image shows the results for the top right corner of the screen (646a64). I think it's pretty clear that the screen has different color tints (green in the upper right corner, pink elsewhere).