I have serious questions about whether the plugin actually has a larger gamut than the driver (as has been stated many times, including by Michael Reichmann).
Here is what I did to make profiles:
1) Followed my own instructions in the Wiki under Creating Custom Profiles :-)
See here for the exact settings:http://canonipf5000.wikispaces.com/Creatin...on-Canon+Papers
2) Printed Bill Atkinson 1728 patch target through the driver, and again through the plugin. Paper is Canon Heavyweight Satin Photo Paper. Media type: Heavyweight Satin Photo Paper. Settings exactly as specified on Wiki page. Used unidirectional for plugin, didn't do it for driver (a long story why).
3) Measured with Eye-One Pro without UV cut filter
4) Compared the measurement files in GMB Measure Tool. Very few differences. For Delta E94 (thought to give a more accurate estimate of visual differences):
Total Sample - 0.49
Best 90% - 0.42
Worst 10% - 1.14
Maximum Delta E 94 (biggest difference out of all 1728 patches) - 2.48
5) Created profiles using Profilemaker Pro 5.08 using Large, Paper Gray, Logo Chroma Plus (I know some like Logo Colorful, but I have always found it mushes saturated colors together too much for my taste).
6) Calculated the gamut volume of both profiles in Colorthink Pro:
Driver - 734,000 (yup, this one is a tiny bit larger)
Plugin - 724,000
For comparison, Bill Atkinson's profile for Epson Premium Luster on Epson 9800 has a gamut volume of 737,000. Note that the size does not tell you anything about the shape, which may be much better for one printer than another--depending on what colors you want to print.
7) Compared the resulting profiles in Colorthink Pro. Result: Virtually identical, with just a hair larger gamut for the driver (yup, the driver).
Conclusion: With optimal settings, both driver and plugin gave virtually identical results on Canon Heavyweight Satin Photo Paper. The driver had just a hair larger gamut. The gamut was quite good for both.
Hypothesis: the smaller gamut reported for the driver previously may be due to incorrect settings in the driver when the profile is made, e.g., Color Match not turned off [Note Color Match is a specific setting in the driver, not the ColorMatch color space]. There is precedent for this, as Epson printers with no color adjustment have a larger gamut than if you profile them with some kind of color adjustment set in the driver.
To see an image with the comparisons for the patches in Measure Tool and the Delta E and Delta E 90 values, see this thread:http://canonipf5000.wikispaces.com/message/view/FAQ/275183