I used an older kit a family member had made by X-Rite. I beleive this is the company that turned into the spyder. It uses a puck placed on the LCD and runs a series of tests. Honestly, i didnt notice any difference after the calibration. The screen looked the same to me, except for the fact that the brightness went down. I use sRGB 8-bit for my workflow and i use CS2 for my photo editing. All my photos start in RAW and i then process then from there. I recently created a panoramic of a mountain skyline that measures about 17in tall and 5ft long. Again the photo looked great on the monitor and had late afternoon sun highlights. But when it cane back from an online photo shop it was too dark and i didnt wind up using it. i figured my problem was that my monitor had too high a contrast rate and that is why they looked great on the screen but dark in print. But if that was the case wouldnt the day time photos also be dark. Or is it just that the light shift is more noticable in darker photos? Also, i figured the calibration software would account for this?