can I use paint for science fair project

Hi, my dtr wants to do a science fair project that compares different detergents and effect on stain removal. Her teacher liked the idea but said it needed to be measured accurately, not just eyeballing the differences. Somewhere online someone commented that this could be measured by taking digital photos of each fabric and importing into Paint and using Paint to " find the average of the RGB values to see which one is lightest". I have no idea what this means or how to do it. Any help would be greatly appreciated.

hmm, well i certainly wouldn't use paint (as supplied with windows 7), it just isn't sophisticated enough to display rgb values.

you could use the freebie (and very goodie paint.net) to do the job, though.

ok, let's now explain RGB values:

in simple terms, colours on a computer can be measured by their rgb value - how much red, green and blue there is. each of these colours is given a number, generally between 0 and 255.

so a bright red would be 255,0,0 because there is a lot of red with no green and blue, whereas a bright yellow would be more like 255,255,0 as there's lots of red and green but no blue.

pure black is 0,0,0 and white is 255,255,255. a bright clean t-shirt (for example) would be closer to the high end than a dirty one (if they were the same colour to begin with, and were photographed under the same light conditions.)

you could take photos of shirts, load these photos up in paint.net or similar powerful photo-editing program, and use a tool to measure the rgb values of the photos.

however, i'm not sure if it's truly an accurate way to determine dirtiness...although it may do for a simple school project.

i've tried to keep it simple, and i hope i've explained things well.

do post back for more help or info.

oh, and welcome to sevenforums!

thank you so much! Your explanation was so simple to understand. I downloaded paint.net and have searched how to assess the RGB values and couldn't find answer so posted my question on forum there. Hopefully someone over there can help us with this. I really appreciate you taking the time so write such a thorough explanation of the RGB values. My dtr will be able to use that description in her write up. Have a great day!

i'm glad i could help, momweber, there are many ways of doing this,and paint.net was the first tool that came to mind.

you need to use the colour-picker in paint.net.

first, click the 'More>>' button in the colors box.

then select the color picker tool (next to the pencil).

then when you move it over the image, and click certain points, the rgb values will be displayed.

ask if you need more help. :)

Thanks so very much for showing me that! That is exactly what I was trying to figure out. Don't know if averaging the three values would be scientific in determining whiteness but it looks good to me. I appreciate you help on this! Take care.