Tip 78: Avoid having to dim the lights
People often say that you should dim the lights when you begin your presentation so that your audience can see your slides better. In fact, in some cultures, it is considered good manners and a sign of great respect towards the speaker for a member of the audience to dim the lights when the presentation begins.
There are several problems with this though. First and foremost, allowing the lights to be dimmed at the start of the presentation sends a strong message to your audience that the key focus of the presentation is the slides. It elevates the slides to a position higher than the person presenting them. The slides assume an importance greater than the human being who is delivering the presentation. Your audience understands that you are giving preference to your slides over yourself – you are dimming the lights so that the slides can be seen at the expense of being seen yourself. You are giving a non-verbal cue to your audience which states that they should be focusing on the slides rather than on you.
This should not normally be the case. Your audience came to see you, to hear you, to interact with you, to discuss with you, to benefit from your presence. The slides should be a tool for you. They should be subservient to you, your aims and your objectives. Your audience should be looking at you more than the screen.
When you dim the lights, you are hiding in the dark. Non-verbal communication is a very important part of the skill-set of the successful speaker. When you dim the lights, you make it much more difficult for you to project non-verbal cues onto your audience. In particular, your facial expressions will be very difficult to see. You put yourself at an immediate disadvantage when you dim the lights, because connecting with, engaging and persuading your audience suddenly becomes harder.
Also, when you dim the lights, you make it harder for you to read any written notes or prompts that you may have. Just as your audience cannot see you, you cannot pick up on your audience’s non-verbal feedback cues. You may also help your audience fall asleep when the lights are low, especially if you are presenting straight after lunch!
The bad habit of turning lights down started in the days of 35mm slides and slide projectors which were not really bright enough to be seen with the lights on. Today’s modern projectors are usually bright enough to be used comfortably without dimming the lights.
The only real reason to dim the lights is when the detail of a technical image is too important to miss. You should then dim the lights while displaying the image, and then put them on again when you move to the next slide.
« Previous: Tip 77: Take photos of your equipment with you
Import citation into 
