Selecting the Right Front Projection Screen Fabric

Selecting the Right Front Projection Screen Fabric

There are a number of basic considerations you have to consider to arrive at the right projector screen surface. Projection method, ambient light, display brightness, seating layout, projector placement, and image detail are all important issues to consider when selecting a projector screen.

Equally important is the projection screen maintenance; this is something many fail to think about at the time of purchase but regular projection screen maintenance is important to ensure that your projector screen continues to deliver the very best images years down the line.

Understanding how these issues impact image performance is essential prior to choosing a projector screen surface. Many would argue that most major projection screen manufacturers' websites include easy-to-fill checklists which once completed, would automatically present you with their recommended screen fabric for your application.

This is true and to a certain extent, these checklists and screen calculators render the selecting a projection screen a straight forward one. Yet we still say that having a proper understanding of the basic projector screen selection criteria is the only way to ensure you make the right choice.

Projection Screen Surface - Selection Criteria

1: Projector Type 

The type of projector screen surface to use is partially dependent on the projection technology of your video projector. Common technologies in the home theater area include 3-LCD, single and three-chip DLP, and LCoS; most of these video projectors use a metal halide bulb as their light source though a few make use of an LED bulb.

Each of these technologies handles brightness, contrast and color intensity in a different manner. Hence projection screen manufacturers have developed specially formulated color corrected screen surfaces that best complement these different imaging technologies.

2: Ambient Light 

Any projected image is at its best when viewed in total darkness, this being so independent of the projector brightness output. However we live in an imperfect world where not everything is under our full control.

Obviously, the first step is to minimize ambient light during a movie, in particular, avoid any stray light falling direct onto the projector screen as this causes the projected image to washout. However, selecting a suitable high contrast projection screen surface can still help you enjoy an image with a sufficient contrast even under moderate ambient light levels.

3: Projected Image Brightness

The brightness output level of your projector is a measure of the projector output power in terms of light intensity. Yet, it is important to realize that the end projected image brightness―or image luminescence―is a different issue as brightness falls in proportion to the area of the projected image size.

This means that the bigger your projected image is, the dimmer it will look for a fixed level of projector brightness.  At the same time, it is extremely important that you do not end up with a too bright an image that would be uncomfortable on the eyes of the viewers. This necessitates the need to match the screen gain with the projector output level, screen size and ambient light. This also means that one cannot proceed with a projection screen purchase in isolation from your video projector.

We discuss this subject in more detail in the third part in this series of projection screen guides.

4: Room Layout

The Society of Motion Pictures and Television Engineers (SMPTE) recommends that for the best viewing experience, the ideal screen size for home theater use should occupy a 30-degree field of view in the horizontal plan at the seating position. This in itself limits the seating area in your home theater room. This 30 degrees field of view is necessary for a person to feel immersed into the movie action.

Some projection screen companies recommend limiting the seating area to approximately 30 degrees from either side to the center of the projector screen; this in effect makes for a 60-degree field of view. This may seem in contradiction to the SMPTE recommendation. But this 60-degree represents the limit beyond which sitting at the extreme sides of the projector screen would be too uncomfortable for normal viewing; it does not represent the ideal seating in the home theater.

Irrespective of the above viewing angles, if your home theater room configuration calls for a wider viewing angle, make sure you use suitable projector screen surface that can maintain adequate image brightness even at extreme viewing angles. This is important as all projection surfaces have a defined angle of view beyond which the projected image would lose its brightness at a rate that is dependent on the projection surface itself.

However, no matter how wide is your room, never loose perspective of the 30-degree SMPTE recommendation for an immersive experience, and even more so, the 60-degree limitation for comfortable viewing.

For more information on viewing distance and home theater seating, please refer to the following guides appearing on our site:

TV Viewing Distance: Discussing viewing distance versus screen size

Home Theater Seating: Guide to correct seating layout

5: Projector Placement 

Projector placement with respect to the projection screen is another important factor to consider when selecting a projection screen surface. The issue mainly arises when making use of a high-gain projection screen; placing your video projector on a floor-stand would require a different type of screen surface than when the projector is ceiling mounted. Why?

When the projector is positioned on the same side of the normal to the screen center as the audience, i.e. the floor mounted version, use should be made of a high gain screen with a retro-reflective surface.If the projector and the audience are on opposite sides of the normal to the screen (ceiling mounted version), use should be made of a high gain screen with an angular reflective surface; these reflect light at the same angle it hits the screen surface.

6: Projected Image Detail

This is all a matter of whether you are displaying standard or high definition content.

Screen surface is not much of an issue with standard definition video. But to fully enjoy the fine image detail supported by today's 1080p high definition video projectors especially at close viewing distances, you need to use a screen with an exceptionally smooth surface.

7: Screen Maintenance 

Hardly considered during a projector screen purchase, yet to get the best performance, the screen surface should be kept clean all the time.

While in general this is not a problem especially in the dedicated home theater room, there are situations where the screen surface may be subject to a higher level of airborne debris and dust that may settle on the surface. However, more problematic is the case where the screen surface may be subject to potential soiling or even damage from constant handling.

Under such circumstances, an easy to clean screen surface is a pre-requisite for continued best performance over time.

More please refer to Cynthia Screen