Hi!
I m just newbie in graphic/ image editing…
I am looking for software (preferable, free) that could do the following:
Are you looking to cut up that image into those cells?
What is your final output intention?
.5mm is only 20/1000" or 20 mils. If you are trying to give those grid lines any kind of printable stroke thickness, you are pushing the definition of Hairline on some printers. A lot of printers have a default “hairline” and won’t go below that.
I m sorry I do not understand what you mean by “cut up”.
I ll try to be more concrete.
Let say I have several colors in my image (say 3-5).
I want to get final matrix with coordinates and its color.
Then I want to do a printable grid with clear colors of my cells.
Your note about printer resolution was very useful for me so lets say I divide initial A4 to 4 parts (A6) so then I can get the more resolution (2 mm). Am I right?
After uploading the image? Lay on it PRINTABLE? Final matrix? Clear colors?
Unfortunately, this doesn’t make a whole lot of sense. You’ve tried to clarify, but your question and terminology are still very confusing. Perhaps there’s a language barrier we’re both dealing with.
He wants to place an image then overlay it with a printable grid and somehow relate the colors in the boxes of the grid to x-y coordinates.
After that, I’m lost too.
I’m pretty sure it isn’t going to be a graphic design program that does this.
Knowing the reason why they want to do this would be helpful as well.
They might be barking up the wrong tree.
If the purpose is to extract numerical color value data from image grids, I’m not sure why physical, mechanical processes would be involved. It seems more like a programming problem involving image segmentation or superpixel algorithms. I suspect it could be done using python, but I wouldn’t have a clue as to how to go about it.
I may be wrong, because it’s hard to fully understand what you want to do … but perhaps look into using Rasterbator They can take an image, output it to any size (such as A4) and turn the image into a mosaic of cells if you want that you can deal with individually in something like Illustrator.
caveat: it may take some playing around with the settings to get you want. But then again, its still not 100% clear what you want, but you may at least want to take a look at it.
I just checked. The minimum size for rasterbator is 3mm mosaic (they do much more than just mosaic squares.) But, if you want to "trick the system to get 1/2mm squares. Set your initial size at 6 times an A4 size (you can enter in dimensions), select 3mm squares, and then open the final PDF in illustrator and shrink everything down to 1/6 size. Voila, an A4 with 1/2mm square mosaic of an image. And it’s all vector, each square can be manipulated.
I suspect we’re misunderstanding, but another half-baked, low-tech way to approximate those values using off-the-shelf software would be to just use Photoshop to resample the image to a 1:1 match with the grid matrix, then determine values for each of the resultant pixels in the lower-res image. With a little work, a RegEx script could probably be written to extract the color values from the image file. This would, of course, yield averaged values for every grid segment from the original image instead of point/pixel-specific values from the grid overlap coordinates.
Thank you all 
Sorry for my English.
Please ignore my final aim and my explanations about it…
What I am looking for is like a “all borders” Excel feature.
I want to define the size of the cell by myself.
I want every cell to have clear XY coordinates.
And that grid I want laying on the uploaded image.
Then I want to print it together. It was a very useful note about the printer’s resolution but I can overcome it just by dividing my initial image. It s not an issue.
Just for now it would be enough for me.
Thank you for rasterbator recommendation. I ll check it but to tell the truth I prefer some light desktop application ( free? it would be excellent).
Hope I was more clear