Lighting for color matching

[andy photenas]

Hello all I am trying to get colors and flash down in my shop. I did read this nice link from the forum
http://www.sawmillcreek.org/content....y-Jack-Lindsey

I cant seem to get a few things right and I wonder what kind of input you guys may have for this?

My first issues is how should you place lighting so that you can see flash when you spray ? Atm I move each door in front of a light where i have a table and can see the reflection of it in the finish on that door. The issue with this is i need to move ever door for every coat and then move it again right after I apply finish to it this is slow and tiring. Does anyone spray in a room where you see the flash in say 10-20 doors so you dont need to move them each time and still see flash to control finish?

The other issue is color matching now im sure this is a large can of worms here. I know that different lights have different spectrum and so under those different spectrum's the same door can look to be an exact match or not even close. How does one do this so as not to run into problems later when you bring this to another persons house and the lighting is different?

[Andy Giddings]

Andy, if you're dealing with painted finishes, I've always found Sherwin Williams good for matching a painted finish to a custom tint of their products. Take the finished article to the store and they'll produce a tinted finish that will match it within a day. Of course stains are a different animal. As for lighting in the workshop/finishing area, I'll leave that to the subject matter experts

[andy photenas]

Sometimes its tough to get what im thinking out in words, I did not mention what I am actually doing! I am trying to learn to use stains and toners. now with wiping stains its fairly easy as soon as you have chosen a stain but with toners you need to control the intensity of the color by how much you put on. this is very hard to see and try to match one door that I keep in the room next to where I am spraying in order to try to match the look on that door. Also the colors change when they are wet so that makes it even harder to get right. This is standard for the big company's So im guessing its fairly easy as soon as you get it right. For now I have not done a full kitchen with any toner other then a white bleach look that is a pure pigment toner. and for the colors I have managed to do. I was able to use a wiping stain because they were on oak but maple and cherry are not very happy with wiping stains so toners are suggested that is my reason for trying to get this down.
This is the reason I need to learn how to make a proper lighting system for this.

[Andy Giddings]

Sometimes its tough to get what im thinking out in words, I did not mention what I am actually doing! I am trying to learn to use stains and toners. now with wiping stains its fairly easy as soon as you have chosen a stain but with toners you need to control the intensity of the color by how much you put on. this is very hard to see and try to match one door that I keep in the room next to where I am spraying in order to try to match the look on that door. Also the colors change when they are wet so that makes it even harder to get right. This is standard for the big company's So im guessing its fairly easy as soon as you get it right. For now I have not done a full kitchen with any toner other then a white bleach look that is a pure pigment toner. and for the colors I have managed to do. I was able to use a wiping stain because they were on oak but maple and cherry are not very happy with wiping stains so toners are suggested that is my reason for trying to get this down.
This is the reason I need to learn how to make a proper lighting system for this.

Andy, as its stains you're working on, you might want to try searching over on Woodweb and/or posting this in the Finishing forum to get more answers. Here's one Woodweb knowledge base article http://www.woodweb.com/knowledge_bas..._Matching.html

[Jason Roehl]

For flash, you need low-angle light.

For color-matching, that is a HUGE can of worms. At the lowest level, you need high CRI (color rendering index) lighting. However, different colorants will peak in different types of lighting. So, say you have a piece finished with Brand X, and you match it with Brand Y of finish in your shop, lit entirely with 4000K, 90 CRI lighting. Now you take the piece into a home that has almost entirely 2700K incandescent lighting. Brand X's pigments may have reflected the light differently than Brand Y's, so what was a match in fluorescent lighting, now is not in incandescent. There is a technical name for this particular phenomenon, but it escapes me at the moment.

[Charlie Barnes]

Regarding the color matching question, I agree with Jason that it's actually very complicated. We deal with that on a regular basis in my group in the automotive industry. I've been to a multi-day class on color matching variables that barely scratched the surface. While it's very easy to get lost in all of the technical elements, my best advice is to use the same lighting in the same environment. It doesn't matter if it matches perfectly with your shop lighting or outside at high noon if that's not where the project is going to be seen most of the time.

Good luck.

Charlie

[Wayne Lomman]

Andy, I have been polishing and colour matching for a considerable number of decades and what you are asking is really encouraging to me because it shows you are thinking which means you will learn.

First the reflection issue. One of the other guys said low angle light and that is correct. You can use a portable light stand or permanent fixtures. Portable can be a battery powered unit these days. No leads to get in the way and safe to use.

Lighting colour is very important as you say. The problem is that you are never going to replicate the colour of light in everyone's house. That's impossible. What you do is try to replicate daylight. Every light fixture maker swears theirs is daylight and they are all different. What you have to do is have an array of lights over your colour matching area and mix 2 or 3 colours of white light. Use some that are warmer and some that are more bluish. Evenly distribute them throughout your array and you have the best you can do. Like colour matching, this is art not science. Mind you, the best artificial light I ever saw was in an operating theatre last year (large splinter removal...) which had a massive array of LEDs mostly white but with a scattering of red, blue and green ones

Finally, it's much better to have a turntable workstation in front of your extractor fan and do each door individually and return them to a drying rack. The finish will be better and you will be working in consistent light. Set up so your movements are efficient. Cheers