Several hundred images in, realised analyse particle measurements doesn't give the result I thought it did

Hi all,
So I have around 1.5k images I am analysing in ImageJ. I am counting stained cells in colonic mucosa stained with IHC. My “green” stain I was counting by selecting a target area, thresholding then using analyse particles to count the number of stained cells. This seems to work well enough.
The issue is the “area” output in analyse particle. I assumed this was the total area within the thresholded and selected area. But I actually think this is the area of the number of counted cells. I.e. there are 2 cells that make up 100 pixel instead of ther are 2 cells in a 100 pixel area.
First of all is this true?
Second of all is there any way I can salvage this without having to go back through the hundreds of images I have already analysed and redoing the area calculation?

thanks for your help

Not entirely sure I follow the question, but the total area is what it says it is, the total area of all segmented objects. That is why the Average Area x2 = the total area. The count is the number of objects that were segmented.

If all of the hundred images were run through a macro, then you would need to add an additional analyze particles step for your first threshold. If you saved the steps, or saved intermediate images (masks) you may be able to write a different macro to recalculate the parts you need.

Thanks for your reply,
What i want as a measurement of area, is the number of pixels within that selectred area above in white.
That is what i thought the total area result gives, but it gives the number of pixels the count makes up.
As a final output i want the measurement of cells/ mm2 and for that i need cells/ pixel
It looks like I need to go back through all these analysed images, select the area again and “measure” to get the area of the selected region

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dear @lrbaumard
could you please upload here that image so we can check?
this one that give you the risulta posted in the screenshot

thanks