Quick - what's a better slide color: gray or red? Almost everyone will say gray is far better as a slide color than red. Most of the time we agree, but then, color in itself is a fickle subject because what may work most of the time may not work in a different scenario. Worse, a color that's not imaginable as a slide color may look attractive. Yes, stranger things have happened in the unexplainable world of color.
Let's just imagine that it has been a long day. You may have also had a long flight that arrived early in the morning. The conference sessions started around 9 am and now after a few sessions and a heavy lunch, you will have to attend another important session. As you enter the dimly lit session room, you can already see the first slide projected. The slide's light gray in color, and has deep blue text along with some muted pictures. Yes, the slide may win full marks for being understated, elegant, and subtle. But, that does not work well for two obvious reasons. First of all, many attendees are tired after a long day and a heavy lunch, and gray may appear depressing to them. Secondly, the colors of the slides make them feel calm and peaceful, exactly the sentiment they are trying to fight. The audience at this time wants to be awake, lively, and attentive. So, maybe some red may have worked better than gray?
Doesn't choosing red over gray sound a little crazy? But in the end, you have to understand that color influences audiences like nothing else. And your choice of slide colors needs to be influenced by a whole array of factors such as the time of the day, even the weather and season, the international composition of your audience, and even their age.
And even that's like putting "color" at a very basic level. There's so much more to color. Knowing more about color will help you create better slides.
Do remember that audiences make lasting impressions when they see your first slide. And, color is certainly the most important part of that impression. They need not read one word of text or even explore your pictures closely to ascertain color. Color is something we absorb, appreciate, and then ascertain in a split second.
About choosing red over gray, if we had to make that decision, then we would have chosen a red that had plenty of gray in it! Maybe a non-saturated red that's like a less bright variation of cherry? So remember, color can always be brightened, saturated, or neutralized (see Figure 1). It depends upon what works best for your audience, your topic, and you.
Figure 1: Reds and grays
Yes, you need to understand color theory better to understand color. And color theory is not really difficult at all. In fact, color theory is just a little science combined with some art. Learn a few guidelines and you may not become a color expert, but you will still know enough to make awesome color decisions.
Colors: Learning Color (Index Page)