Color Analysis 2

[JohnNabors]

Here's an offbeat one for you folks..

I'm trying to find a portable, self contained device to measure the color of painted galvaneal panels to obtain a specific RGB value. The issue is that a supplier of sound attenuation enclosures we use on large, diesel driven water pumps is failing to properly match the color of the powder coated enclosures to that of our painted pumps. I want to find a portable color sensor so that the supplier and our QA folks will be able to measure the color with identical devices, obtain the RGB values, and determine if those values fall within a specified tolerance. I have found one such color sensor made by HunterLab and have requested product and pricing information on it, but I find it hard to believe that there is only one manufacturer for such a device. Has anyone heard of any others?

By the way, it is not helping matters that the color in question is proprietary to our company and cannot be purchased directly by anyone else.

Hope someone can help. -John

 

[tripleZ]

Do you know anybody in or work near a carpet or upholstery manufacturing facility? I remember one of the senior design project groups from Virginia Tech working with a carpet manufacturing company somewhere in southwestern VA. They used hand-held meters like you're describing for their project (pertained to matching thread color content variance between lots). If you can get ahold of an engineer from one of those companies (weird cold call I know, but it might work), they might be able to give you some insight.

 

[PSE]

http://www.xrite.com

Regards,

 

[JohnNabors]

PSE-

Thanks for the link if only because it let me know I'm barking up the wrong tree financially. If I took a $9500 requisition for this device just to determine just what shade of blue we are looking at to my boss he would have a heart attack from laughing. I like my boss. I don't want that to happen to him.

Looks like I'm going to have to go a little out of the box on this one. I'm thinking of trying something along the lines of Photoshop to do color analysis from a digital photo.

-John

 

[griffengm]

JohnNabors,
Seems like if you can get a chip of each and take them to your local paint or hardware store they should be able to check the match or at least give you the values. Or maybe I think too highly of my helpful hardware man?

Griffy

 

[MadMango]

Matching colors from digital photos can be tricky as well, as you need to ensure your monitor is properly calibrated to display the correct colors.

Have a read through

http://www.normankoren.com/makingfineprints1A.html

[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green]
Steven K. Roberts, Technomad
Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[JohnNabors]

MadMango-

I gave myself a 'duh' slap about 10 minutes after I posted that.. In order to get a valid set of RGB values for comparison I would have to find a way to insure IDENTICAL lighting for both photos. I like Griffy's idea of using the local paint store or even checking in with our paint supplier. I would have the enclosure supplier powder coat a 2x2" coupon of the galvaneal and pass that on to whoever is going to do the test. I just need to find out what will be the format of the test result.

Thank you very much everyone! -John

 

[Jabberwocky]

http://www.pantone.com/products/pro...Area=8&idProduct=151&idArticleType_Products=0

I hope this isn't the same thing as the xrite link, I couldn't get that to work. I also don't know if this will give you RGB values or just their Pantone number, but you should still be able to use it for reference.

I suppose if you wanted to go even cheaper you could buy a light and a light sensor (CCD?) and rig up your own little unit.

 

[PSE]

JohnNabors,

Digital photo matching may introduce another set of issues as MadMango indicates. Monitors, cameras, scanners, printers, inks, papers etc each have their own color gamut. Depending upon the accuracy you are looking for, you would need to profile each appropriate device and match the gamut ranges. RGB colorspace is native to and relative to each individual device and does not translate directly between them. Your local paint store may be able to measure the color but the output from the device is more likely to give a formulation for creating a paint to match than actual color data from the sample. Most operators at the paint store are not likely to be able to get spectral data out of the device.

Regards,

 

[FACS]

You can take your color chip to the hardware store, but they are only able to give you a formula for making the color, and that will depend on the Base they are using. You may not be able to do much with it.

http://www.americaninstrument.com/equipment/Spectrophotometers-Colorimeters.asp

Charlie

http://www.facsco.com

 

[rhodie]

Minolta manufactures a cheap colorimeter, giving L*A*B* values. <$600

Unless you'd like to match colors to a painter's chipdeck, this is the cheapest method to gather the information you are needing.

 

[randi]

In the industry there are Munsel colour tolerance chips that are available for metal paint finishes or plastic materials.

BYT Gardener is another supplier taht supplies all kind of equipment for checking pint finishes.

Any "Metal Finsihing" magazine could list a number of suppliers of testing machines.

 

[jck26]

This may sound basic, but can the two groups use the same spec paint or paint supplier then work it out between themselves?

Just a thought.

jck26