Call our experts 0800 073 0833
Read our
customer reviews
>

What is gain on a projector screen

Projectorpoint Explainer - Screen Vs Wall

Understanding Gain on Projector Screens: What It Is and Why It Matters

There are several factors that can affect a projector screen’s quality and brightness, and gain is one of them. This article will uncover what this term means and how it plays a role in a perceived image. 

What Is Gain?

A projector works by reflecting the light back from a screen to your eyes. Screen gain is the amount of reflective lumens from a projector to the viewer, and the number determines the image’s quality and width of the viewing angle. 

Gain is presented as a ratio, and the higher the number, the brighter the image on the screen will appear. Although, a higher gain projector doesn’t automatically equal better (more on this later). 

There are many references to a projector’s gain, with ‘high’ and ‘low’ being the most popular. For example, a 1.5 high-gain screen reflects 50 percent more light than would normally be sent back from a whiteboard. Alternatively, a grey projector screen with a 0.8 low-grain surface reflects 80 percent of the light emitted by the projector, ensuring a clear and vivid image display.

Why Is Gain Important for Projector Screens?

Gain affects the projector’s brightness and quality of viewing angles. In particular, a higher gain projector doesn’t automatically equal better. While it can provide a brighter image for some angles, other perspectives can experience a diminished brightness. A smaller viewing angle means a smaller area that viewers must sit in to relish in the screen’s maximum brightness. 

Determining the Ideal Gain for Your Projector Screen

The standard gain for a projector screen is 1.0. This rating shows that the reflected brightness is equal on all sides and still visible from multiple angles. But this doesn’t mean that a 1.0 gain is best for all viewers and purposes. 

Pros of high gain:

  • Provides clear and visible images in bright settings
  • Makes dark conditions appear more visible 
  • Reflects minimal light from the walls and ceiling  
  • Great for eliminating light from fabric screens that resist general lighting

Cons of high gain:

  • Reduced viewing angle for those not in the middle
  • Requires viewers to sit directly opposite the screen for optimal brightness
  • Not bright enough for a larger audience due to restrictive viewing angles 

Alternatively, a low-gain projector screen offers a vibrant contrast and is ideal for environments where ambient light is unavailable, such as in small rooms or home cinemas. Here are some pros and cons of low gain:

Pros of low gain:

  • Offers a more expansive viewing angle for larger audiences 
  • Diffuses light more evenly across a wider angle for an equal viewing experience
  • Reduces projector brightness for an indoor setting

Cons of low gain:

  • Not ideal for outdoor viewing due to the reduced brightness
  • Rejects some lights from the projector
  • Doesn’t provide ample contract to view all images clearly

Common Mistakes When Choosing a Screen with the Wrong Gain

Projector screens with a gain of 1.0 to 1.3 typically have wide viewing cones. However, higher gains tend to have narrower viewing cones, so you’ll need to adjust your seating arrangement so everyone is inside the viewing cone. The higher the gain, the more likely everyone will need to hotspot in the centre. A common mistake is selecting a high gain to use in a dark room with projectors that don’t render blacks clearly. 

Gains below 1.0 reduce image brightness, which isn’t bad because it can improve contrast by light bouncing off the screen and reflecting back onto it from light-coloured objects or walls. A common mistake is choosing too low of a gain in bright rooms, as images will suffer from glares and appear much duller. 

Screen-gain

Source: Projector Central

How to Measure Gain?

Screen gain is measured from the middle of the screen’s viewpoint, which is the brightest reflective point on the projector. When measuring the screen brightness from the side, the projected image’s light is dimmer than the centre.

The optimal viewing window is perpendicular to the screen, also known as peak gain. If you position yourself to the side of the screen at an angle, the brightness will drop off. When the gain reading drops to 50 per cent of the peak gain, it’s known as a half gain viewing angle since the viewing will experience half the brightness of a person positioned at the centre position.

Tools and Equipment Required for Measuring Gain

To measure gain on a projector screen, you will need a few tools, including:

  1. Light meter: A light meter is a device that measures the amount of light that is reflected off the screen. It is necessary for calculating the gain of the screen.
  2. Projector: You will need a projector to project an image onto the screen. This will allow you to measure the amount of light that is reflected back.
  3. Test pattern: A test pattern is a specific image tused to measure a screen’s gain It usually consists of a series of lines or dots that are spaced at specific intervals.
  4. Tape measure: You need to measure the distance between the projector and the screen. This is important for calculating the size of the projected image and determining the optimal placement of the projector.
  5. Calculator: A calculator is helpful in calculating the gain of the screen. You must use the light meter readings and other measurements to perform the necessary calculations.
  6. Pen and paper: Take notes or record your measurements as you go along. This can help you keep track of your progress and ensure that you get accurate results.

Steps to Measuring Gain on a Projector Screen

  1. Set up the projector and screen: Position the projector and screen in a suitable location. Ensure that the projector is aligned properly and that the screen is level.
  2. Set up the test pattern: Display a test pattern on the screen. This can be done by connecting a laptop or other device to the projector and selecting a test pattern image.
  3. Measure the distance: Measure the distance between the projector and screen. This is important for calculating the size of the projected image.
  4. Measure the light: Use a light meter to measure the light reflected off the screen. Take multiple measurements at different points on the screen.
  5. Calculate the gain: Use the light meter readings and other measurements to calculate the screen’s gain. Gain is calculated by dividing the amount of light reflected off the screen by the amount of light that would be reflected off a standard reference screen.
  6. Record the results: Record your measurements and calculations. This will allow you to compare the gain of different screens or track changes over time.
  7. Repeat the process: Repeat the measurement process with different screens or under different conditions to obtain more accurate results.

Measuring gain can be a complex process and may require some technical knowledge. If you are unsure about any process step, it is best to consult with a professional.

FAQs

What Is the Ideal Gain for a Home Theater?

A 1.0 gain diffuses light evenly across all directions, making images more visible from a range of viewing angles.

Does the Size of the Projector Screen Affect Gain?

Yes, since a large screen will provide a brighter image across a wider section of the screen.

Can You Improve Gain Without Changing Your Projector Screen?

Yes, you can adjust the lighting in your environment by switching to a low-lit room or in natural lighting.

Summary

Gain is an important factor when choosing a projector screen, as it affects the projected image’s brightness and quality for viewers in different positions in a room. A 1.0 gain diffuses light evenly across all directions, enabling viewers to sit to the left and right of the screen without their position affecting the image quality and brightness. For those sitting off-centre, the brightness of an image can alter dramatically, so a high-gain screen can pose more limitations for large crowds.

Contact Us
cross
Select the fields to be shown. Others will be hidden. Drag and drop to rearrange the order.
  • Image
  • Add to cart
  • Availability
  • Price
  • Resolution
  • Brightness (Lumens)
  • Contrast Ratio
  • pa_aspectratio
  • Lens Type
  • Calc ThrowWidthRatio Min
  • Calc ThrowWidthRatio Max
  • Light Source
  • Weight
Click outside to hide the comparison bar
Compare