Shop Lighting
You finish up a knife at home and bring it out to show at a meeting, gun show, knife show or maybe just the local sporting goods store. You take out your knife and it looks totally different. Scratches on the bolsters, hooks and swirls on the blade... it's almost as if you brought the wrong knife. We all know you didn't bring the wrong one though, you just took it under a different light source. Does this story sound familiar?
You'll see many makers talk about how important lighting in their shop is, you'll hear “you can never have too much light” so often throughout the knife making community that you might think it's our mantra. Along with our little slogan also comes a belief that you need as many different light sources as possible. Some makers will check their knives under incandescent light, fluorescent light, halogen shop lamps and bright sunlight before they're satisfied.
Even after all of this checking and rechecking when you get out to the knife or gun shows you still run the risk of those little nuances showing up under the show lighting. Why, after all of this effort, are there still scratches in the blade? More importantly, how do we get rid of them? These are the questions I began to ask after a recent discussion with Alan Folts and Andrew McLurkin.
Both seemed to agree that the Southeastern show had the most humbling lighting of all. During the discussion, Andrew (unknowingly) gave me a ball to run with – Mercury Vapor Lamps. The consensus in the car that day was that these lights are far more honest than most of us would like them to be.
So the key, the answer to the questions I posed above lies in understanding the Mercury Vapor HID and how it differs from our shop lighting. The answer actually becomes quite clear if we start looking at the color temperature of our shop lighting. Here is a basic breakdown of the temperatures, rated in Kelvin (K):
High Pressure Sodium Lamps: 2100K
Incandescent Lamps: 2800-2900K
Halogen Lamps: 2800-3400K (typical drop lamps are in the 3200K range)
Typical Fluorescent shop lighting 3000K (warm white) - 4100K (cool white)
Metal Halide Lamps: 3000K (frosted) - 4200K (clear)
Mercury Vapor Lamps: 4100K (frosted) - 5700K (clear)
Daylight: 5000-6500K
Metal Halide and Mercury Vapor lamps are probably two of the three most common types of industrial lighting (fluorescent being the third). These are the two that you're most likely to find in the large open areas with high ceilings that are so typical of knife and gun shows. The lamps have a very high light output per watt, can be reflected well and have extremely long lives which make them indispensable for these settings.
What may or may not be obvious from the information above is that we tend to shoot ourselves in the foot when it comes to shop lighting. All of the common lights found in makers' shops have color temps far lower than the industrial lamps they'll sit under at a table.
Even with cool white fluorescent and halogen lamps, we're only barely touching the upper ranges of Metal Halide HIDs and the lower end of Mercury Vapor HIDs. I will make you a bet that most makers can't tell you if they have warm white or cool white lights and that they probably don't even care.
OK, Cap, if you're done telling us what we're doing wrong, how about some good news? Do we have to replace all of the lights in our shop with Metal Halide and Sodium Vapor lamps? My answer to that is a qualified “No”. I say qualified because you'll never reproduce the lighting they use in shows unless you get the same type of lamps. There is, however, a silver lining to all of this.
Fluorescent and LED lights offer all but the highest end of color temps. Color correct/full spectrum fluorescents are available in 5000K (and above) and LED lights can be had around 5100K, getting you much closer to the lights we see at shows or on a nice clear day. Even better news is that both of these are available for standard light sockets, which means that you can have a small area with one or two lamps dedicated to giving you “finishing” light. A good LED bulb will run you about $30 and a good full spectrum compact fluorescent should cost less than ten dollars.
Full spectrum lighting is growing more popular as each day passes, as are compact fluorescent lights in general. What this means is that your customers are going to have better lighting to inspect your knives and may become more critical of your products.
For those of us who want to take this even further, there are 6000K fluorescent tubes available for shop lights and you can even buy self-ballasted Mercury Vapor lamps that fit into regular medium base sockets. A clear, 100W Mercury Vapor lamp should give you a 5700K color temp and run you less than $20. Not too bad if it helps you make the best knife you can, even better if it helps you sell it.
, but worth the read. 
