Question: How to calculate Delta E for an area


I am conducting a research and would like to find out the Delta E value for an area.

Basically, I have a picture that I divided into squares in photoshop and would like to compare between different squares.

I can get the LAB values from histogram but I can not use the online Delta E calculators since the values can not be entered ( only up to 100 for L and I am getting more than that in photoshop histogram)

I guess I need to convert photoshop LAB values into CIELAB?

would you please help me. Thank you


Have you tried converting your RGB image to Lab using Image > Type > Lab Stack within ImageJ?