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The photo shows the shade of blue that a client is wanting on his archtop.
He says that it is not the mohawk blue used for the Chinery Collection.
I'm wondering, with all the latest technological advancements, whether the color can be computer analyzed from the jpg and then compensate for the color of the spruce and maple?
All help appreciated.
Nelson

Hey Nelson

Thanks to the lovely art of color profiles and your monitor's color calibration, the color will be different on just about every screen you view the image on. The color is also different depending on the light in the room. That will make it impossible for you to match that way. Can you contact the builder and ask for whatever information they can share?

You can get a screen standardized for color display, but suppose you do and get a color analysis. That is not going to tell you which lacquer dyes to use and in which proportions over your particular set of woods, and in the finish thickness that you are applying.

Tell the client that you can come close, but if he is going to put it alongside another blue guitar and complain if they aren't an exact color match, you won't take the commission. Then work by eye.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I don't think the computer matching is going to work out well. I'd color samples of the spruce and
maple you'll be using, and get the clients agreement on what he likes. You'll need to use color dyes
to change the color of the wood without obscuring the grain. And with the bindings being natural,
you may need to dye the wood before the binding is applied.

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

As I suspected, you're telling me it's still a trial and error process.
I normally do the color by spraying analine over the base coats of clear nitro.
I guess this method has it pro's and con's but it seems to let the grain come thru nicely.
This chatoyance, if I may borrow a term from the gemology folks, especially brings out the best in flamed maple.
(Wish I could say the same for spruce)
Regardless, I do appreciate your feedback and look forward to more.
Best regards

the lighting the photo is taken in the angel of the lense to the surface. Hue of the lighting. Too many uncontrolable variablesto confirm a specific color form a JPG. Then as Howard said actually staining to match is not likely to be perfect. even with in a factory the batch mix es will vary slightly.

Yep, way too many variables. Lighting can change the color, the camera can change the color, the program you use can change the color, a scanner can change the color, the printer and/or printer driver can change the color, the paper you print on can change the color, etc., etc., etc.
Pretty much any degree of separation from actually taking the instrument to a color analyzing machine, you are subject to a color shift, and even then it may not be 100% accurate.
-j.

_________________
“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

If he has access to the guitar, he could take a pantone swatch book and match the colour he wants.

I will probably need to make up some chips to send to the customer for verification of the color.
In further correspondence he indicates that he is wanting an opaque finish in the blue color shown and not
interested in any wood grain showing thru. That is a new one for me and changes everything.
I understand what you guys are saying about differences in monitors, lighting etc.
The guitar and the builder is not accessible to the customer or myself so wondering if the photo
might be just a start in computer matching of the color. I understand that jobbers like NAPA use a portable
scanner to read color and output the recommendation. Anyone familiar with this?
Thanks again.
Nelson

hi Nelson
this may not be of any use - but -
In my professional life I’ve just retired from, this year. I had a member of QC Lab staff whom I trusted to blend to Standard any batch of up to fifteen tones of pigment paste (highly concentrated) in a vessel to within two kilos of blend material - only she did it by eye! and yeah we had all the gizmos which cost us a fortune.
Now this is the kind of person your looking for, any pigment / dye makers / users round you?
yours Geordie

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