Hi Terry,
I think this is what’s going on in your situation.
You were fine with the Eizo because the Color Navigator software works directly with the graphics system inside the Eizo via “DDC.” That way, all you had to do was set your aim points (100cd/m, 2.2, 6500), go through the process and you’d get 100cd/m, 2.2, 6500.
Without this DDC, you had to do things more manually - bringing down the luminance on the HP as you said. It is not uncommon to have to reduce an LCD’s brightness down to zero, or close to it in order to get it in the ballpark of what you need. And as you apparently discovered, some Apple monitors are still too bright even at zero.
The Spyder requires the luminance to be taken care of in the hardware. So, you have to actually be able to turn down your monitor’s backlight to 100 cd/m2 in order to get there. By contrast, the CN software can make use of the graphics card inside the Eizo to meet the desired luminance.
Since you have ProfileMaker, you can use MeasureTool to reduce some of the brightness using the Mac’s video cards for the HP and Apple displays. It’s a bit of a complicated process, but you can do it!
We talked about this elsewhere in ColorForums:
[url]http://one.imports.literateforums.com/t/brightess-at-0-and-still-too-bright-now-what/516/1]
The reason I’m focusing on Luminance so much, is that that is really the first step in getting two displays to match each other. You have to get them putting out the same brightness first, and then the colors fall into line much easier.