[old_tv_nut]

You really have to consider each step of the process and what it does if technically correct, plus where it could go wrong.

The DVD or BluRay was supposedly transferred according to Rec.709/sRGB matrixing, and adjusted by a colorist looking at a calibrated Rec.709/sRGB monitor. This means mostly that the gain of R-Y is going to be increased non-linearly compared to NTSC to make the displayed colors correct. It also means that a display using the intended primaries will limit the colors to the Rec. 709 space.

Now you play it back on an NTSC display that hopefully has been white balanced correctly and has the color difference gains set per NTSC specs. This means that when the signal says pure green or pure red or pure blue, you get pure NTSC green or pure NTSC red or pure NTSC blue, each of the same intensity needed to make white, and zero of the other primaries.

BUT - when the signal on the disk is for pure green, it is expecting a display that produces pure Rec. 709 green, not NTSC green. Colors that are not fully saturated are affected too. Since your NTSC CRT has a wider gamut, it expands the saturation of the colors compared to what the colorist saw or what you should see on a modern HDTV.

So - calibrating the color bars on the NTSC tube will NOT produce correct saturation on picture material unless that material was mastered in NTSC color space. Hence the need to turn down the saturation on the pictures to do an approximate conversion back to the expected Rec. 709 colors.

Unanswered questions: Is Dorothy's dress supposed to be white? Was it actually white on the set? Was it gray tinted, or even slighly blue to prevent an overexposed fluorescent look due to the high contrast of the Technicolor process? Was it actually white on the original prints? I don't think we know.

If you can capture a video frame directly from the BluRay and view it in Photoshop, you could measure the color represented on the disk so you know what you are aiming for. An acceptable substitute is to use your fixed manual camera white balance, turn the color all the way down on the color bars, and make sure the gray scale is neutral in your photos - tweaking the white balance manuallly if needed to make it so. But, even when the white balance is perfect, that is only the first requirement - it still remains that the disk is not mastered in the correct color space for the NTSC display.