Fluorescent Lights Make Grading Difficult at Shows

[Forest City]

I'm just curious if anyone shares my frustration at viewing coins at shows under fluorescent lighting.  The luster on coins looks very dull, and it's hard to tell what they will look like when I get them home.  

Yes, I realize that most dealers have halogen lamps over their cases.  For some reason though, even when I hold a coin under these lamps, the overall ambient lighting still gets in my way.  Does anyone else feel the same or am I alone on this, just curious?  This is mainly an issue with high end coins.  Mid-grade and lower coins aren't really effected.

[Insider]

While the lighting at any coin show is terrible the use of Fluorescent light vs Incandescent light is an interesting topic of discussion.   Both have their uses.  Short and sweet:  Fluorescent light is the ONLY light suitable for counterfeit detection and seeing wear on the high points of a coin that looks to be uncirculated.  Incandescent light shows marks, luster, and hairlines on coins.  

[physics-fan3.14]

Yes, the lighting at shows can sometimes be difficult.

However, as Insider mentions, different types of lights have their different uses. If you are going to a coin show, you pretty much have two options: 

1. Understand that most lights will be fluorescent, and adapt your grading/viewing to the lighting conditions, or

2. Bring your own light. 

When you are at your home/office, you study coins under the same environment every time - there is a certain light you use, the light is the same distance, you use the same loupe. You are familiar with this environment. The challenge in going to a coin show, or an auction viewing, is to figure out how the lighting there changes your view of a coin. This can be difficult, but we've got to work with what we've got - there is no chance that a convention hall will change their lights for a coin show! 

[RWB]

With some exceptions, the type of light source is much less important than the shape of the source and distance from the subject.

One notable exception is judging coin color. This must always be performed with a neutral 18% gray card background and daylight-balanced, broad spectrum light. Proof gold is especially subject to "greenish" coloring that is actually from ambient lights.