EDITED:
Please use the "Medium" patch set posted later, not the "small" target set attached here. This provides much more printer info and, better, lets me actually determine the accuracy of the printer without a round-trip to print Lab values.
The trick is to use a special, reverse lookup by doing an exhaustive search for the Lab values that produce the RGB values from the profile under test.
Sorry for the delay. I've reconfigured the test charts to focus more on neutrals and near neutrals since that is a much bigger problem than how many color patches there are. In fact, it takes some work to get the neutrals printing as well as color patches with color patch counts over about 400!
Attached is a zip file with two sets of charts. One for ACPU/Windows and one for utilities that print profile charts without re-sizing.
See the readme.txt file for more info. From the readme:
---
These charts contains the following:
Regular grid spacing of 4x4x4, 5x5x5, 6x6x6, 7x7x7, 8x8x8, and 9x9x9. Also, for 8x8x8 and smaller grids inset grids are also included which somewhat optimizes (AKA packed grids). Additionally, a partial 17x17x17 grid is included. This grid is all the values from 64, 80, ... 192. It is used to get a measure of the improvment in color patches by testing distributed colors within that RGB region against both it and the 9x9x9, which has exactly twice the spacing. My printers exhibit rapid assymptotic approach to an optimal that occurs around 3,000 patches. This high res subset is designed to compare the benefit witihout having to print the full 4913 patches required for just 17x17x17 grid.
But wait, there's more.
Turns out neutrals and near neutrals are much bigger problems with patch color accuracy deviations much larger. However, this can be improved markedly by a fine RGB grid along the neutrals.
So there are a number of near neutral data sets included. In particular a full, 3 level grid along the neutrals with deviations of 7 and 14 are included as in this pattern:
0 0 0
0 0 7
0 0 14
0 7 0
0 7 7
0 7 14
0 14 0
0 14 7
0 14 14
7 0 0
7 0 7
7 0 14
7 7 0
7 7 7
7 7 14
7 14 0
7 14 7
7 14 14
14 0 0
14 0 7
14 0 14
14 7 0
14 7 7
14 7 14
14 14 0
14 14 7
14 14 14
14 14 21
14 14 28
14 21 14
14 21 21
... to 252
Since these include smaller spacing 7 and 14, the following patterns to make profiles with are "free"
0 0 0
0 0 7
0 7 0
0 7 7
7 0 0
7 0 7
7 7 0
7 7 7
7 7 14
7 14 7
....
And
0 0 0
0 0 14
0 14 0
0 14 14
14 0 0
14 0 14
14 14 0
14 14 14
14 14 28
14 28 14
....
All of this data is used to generate metrics such as the deviations between successive points on a line and deviations of centers from points equi-distant. These metrics correlate highly with actual profile errors printing a large, 100 to multiple hundreds, of independent, gamut distributed color patches. The neutral sets provide similar results for estimating neutral color accuracy. They also highly correlate.
Right now I am running checks on the new, inserted high rez grid and, most importantly, various near neutral RGB sets. Turns out this is a much more critical area than the more general color accuracy in even slightly saturated colors. This reflects the greater sensitivity that Delta E 200 has in this area.
I will be posting metrics and their correlation to actual printed Lab colors distributed evenly in the printable gamuts of my three printers. Focus is on glossy. I use Costco glossy as it's cheap and all my tests v Canon Plat Pro, show the performances on my two Canon's are virtually identical outside of a small gamut shift due to the Plat's warmer white point.