I recently purchased a VideoEQ Pro video calibration tool:
User video calibration normally deals with the 5 common picture controls – brightness, contrast, color (or saturation), hue (or tint), sharpness. In order to adjust these properly, you need video patterns which are commonly available for free in THX dvd’s and lately in Disney blurays. You can find lots of instructions in the web on how to use these patterns.
Professional video calibration goes beyond these basic controls and involves 3 main things:
1) Gray-scale
2) Gamma
3) Color Management
Let me try to explain my understanding of these in as simple a manner possible. Please feel free to comment:
Gray-scale involves the proper balance of the primary colors (red, green and blue) at different luminance levels (which are designated as 0 IRE to 100 IRE). If the 3 colors are properly mixed, you will get white (at 100 IRE) and a shade of gray at any other IRE level. There are many patterns available which show graduations of gray from pure white to black and if the primary colors are not properly mixed, you will note that some shades are pinkish, bluish or greenish. It is quite common in fact for whites to be bluish and blacks to be reddish. In order to properly adjust the gray-scale, you need (1) a spectrophotometer (or something similar) to take readings of gray levels, (2) a dvd, bd or another instrument to produce grays at different luminance levels and (3) software to analyze the readings from the spectrophotometer. The problem is that usually, displays can only adjust the gray scale at 2 points (typically 30 IRE and 80 IRE). You can get a perfect RGB balance at these 2 points and then hope that you get a good balance at other IRE levels. Unfortunately, that often is not the case. There are few displays which can adjust gray-scale at more than 2 points – for example, the JVC RS-25 or RS-35 projectors.
While gray-scale involves the balance of RGB, gamma involves the proper luminance level (relative to the luminance of white) at varying IRE levels. Let us say that at 50 IRE, you may have a perfect balance of RGB but if the luminance level is too low, this would result in a picture which is too dark. If the gamma is not correct, you will get a picture which looks flat, without depth, looks more 2d than 3d. With the correct gamma, you will get the proper shades of colors and therefore you will see fine details such as skin pores, creases on fabrics, etc. Using the same instruments and software as with gray-scale, you can adjust gamma but you encounter the same problem. Most displays allow you to adjust gamma at only 2 points so you may get it right at these 2 points and wrong elsewhere. There are exceptions, of course, such as the Panasonic PT-AE4000 projector which allows you to correct gamma at 10 points.
The last step involves color management, which is basically similar to the “color” and “tint” controls except that for professional calibration, you must make these adjustments for red, green, blue, magenta, cyan and yellow. For each color, you adjust its saturation (closeness to white), brightness (closeness to black) and hue (color mix). If the color management is not correct, even if your gray-scale and gamma are correct, the picture will be inaccurate. The colors may be off or may look artificially saturated. Most displays do not have a color management system. The only ones I am aware of that have them are the JVC RS-25 and RS-35 projectors.
My previous system (even with a DVDO VP50 Pro video processor) only had a 2-point calibration for gray-scale and gamma while it had no color management system. The VideoEQ Pro has an 11-point calibration for gray-scale and gamma and a full color management system. It also allows you to have a very fine control because each calibration point has 1024 steps. Imagine a brightness control that allows you to have 1024 adjustment levels – that’s how this gadget works. You just insert the gadget between the display and the AVR (or in my case, the video processor).
It took some time to get used to how it works. I probably spent more than 15 hours working with it before I was satisfied with the results.
For me, the cost and effort were worth it. There’s a significant improvement in pq. You can see a lot more detail and the picture is more 3d. It’s most noticeable in close-ups of faces – you can see the pores, pimples, blemishes. There is more depth … parang buhay.
I've decided not to post screen shots. They don't do justice to the actual picture.
