Measuring Grey Intensity

[elizabethd37212749]

Hello forum,

Here is my ultimate goal:  I have an image that I want to be able to quantify the amount or intensity of purple on the image.  There are other colors present and there are different shades or purple throughout the image.

I was able to isolate just the purple on the image but going to

Select>Color Range>

Then selecting only the purple on the image-- it changed it from a colored image to now greyscale-- where the darkest shades of purple are dark grey vs little amounts of purple which are a lighter grey.

Now I want to be able to quantify the intensity of the grey on the ENTIRE image (more specifically the entire dish in the image)

Is there any way I can do this?  I have Photoshop CS6.  Also is there a specific format my image needs to be in order to start analyzing-- I found a great approach that I could use already (found here Photoshop Extended: Performing a comparative analysis of bands | lynda.com - YouTube))

https://www.youtube.com/watch?v=v5xLSXMHFr0however whenever I go to

Image>Analysis>Set Measurements Scale (or any other selection in within that tab)  it remains grey meaning I cannot select that item.  The only team I can select is ruler tool which is not what I want.  Here is an image to show you more clearly what I'm talking about (the background is the image I want to analyze)

I hope this makes sense-- let me know if you need clarification.

[c.pfaffenbichler]

First regarding screenshots:

FAQ: How do I capture and post a screen shot or video?

Secondly you may be able to use the Histogram, automating that might take some Scripting.

Photoshop Scripting

Then selecting only the purple on the image-- it changed it from a colored image to now greyscale

Which exact steps are you describing here?

[elizabethd37212749]

Here is my original image.  On the top selection bar I clicked on

Select>Color Range

Then this little window pops up (shown up above)

Right below the save button on the window there are "eyedroppers" that allow you to select the color you want to isolate.  I isolated the purple hues and now the image is greyscale

The darkest grey areas are the most concentration of purple where the light grey areas are where no purple is found.

[c.pfaffenbichler]

But how and why did you arrive at a grayscale image after selecting the Colour Range?

Please post proper screenshots in future, not photographs of your screen.

[elizabethd37212749]

In the pop up box, there is a box that says selection preview and it can convert it into greyscale.

I converted it to greyscale because I thought it would be easier for a program to measure grey intensity versus intensity of all other colors on the image.

[c.pfaffenbichler]

Check out the Histogram.

Have you posted on the Scripting Forum yet?