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PROJECTORS

PROJECTORS

Choosing the Right Projector

If you think back to the last time you went to the movies, it was the big screen that really caught your attention. Sound is critical but the screen is obvious.
Screen size if personal. Think about where you sit in the cinema and chose your size accordingly. If movies are you thing then go for stunning Cinematic Widescreen.
This is much wider than the 16:9 TV format.

Projectors

Light and dynamics is key. A bright picture with deeper more natural colour will impress over size or resolution. We love JVC projection as they really excel in the key areas and boost the highest contrast ability in the market segment.

Because they will also allow a cinemascope format without the expense of extra lens systems. Most of the range happen to be THX and ISF certified. Running big acoustic screen > 3m wide, want more grunt? Check out Barco residential.

These guys build for studios and commercial venues, you don’t get any more REAL than Barco. Before you get too excited prices range from $25K – $400KAU…. 




Room Characteristics

So before purchasing a projector and screen, take a good look at the room you will be placing the video projector and screen in. Is the room of sufficient size to project a large image on the wall area where you intend to place your screen?

Check for ambient light sources, such as windows, french doors, or other factors that would prevent the room from being dark enough for a good video projection experience.

So on the video projector side, here are some additional references that provide tips on what to take into consideration that will affect placement and  performance in relation to a video projection screen: Lens Shift and Keystone, Colour Brightness, Nits and Lumens.

What Nits and Lumens Are

Here is how Nits and Lumens are defined.

Nits: Think of a TV as like the Sun, which emits light directly. A Nit is a measurement of how much light the TV screen sends to your eyes (luminance) within a given area. On a more technical level, a NIT is the amount of light output equal to one candela per square meter.

So to put this into perspective, an average TV may have the capability to output 100 to 200 Nits, while HDR-compatible TVs may have the ability to output 400 to 2,000 nits.

Lumens: Lumens is a general term describing light output, but for video projectors, the most accurate term to use is ANSI Lumens (ANSI stands for America National Standards Institute).

So in relation to Nits, an ANSI lumen is the amount of light that is reflected off of a one square meter area that is one meter from a one candela light source. Think of an image displayed on a video projection screen, or wall as the moon, which reflects light back to the viewer.


Nits vs Lumens

One Nit represents more light than 1 ANSI lumen. The mathematical difference between Nits and Lumens is complex. However, for the consumer comparing a TV with a video projector, one way to put it is 1 Nit as the approximate equivalent of 3.426 ANSI Lumens.

Because using that general reference point, in order to determine the approximate amount of Nits comparable to an approximate number of ANSI lumens, you can multiply the number of Nits by 3.426. If you want to do the reverse, divide the number of Lumens by 3.426.

So for a video projector to achieve a light output equivalent to 1,000 Nits (keep in mind that you are lighting up the same amount of room area and room lighting conditions are the same) – it needs to output as much as 3,426 ANSI Lumens, which is out of range for most dedicated home theater projectors.

However, a projector that can output 1,713 ANSI Lumens, which is easily attainable, can approximately match a TV that has a light output of 500 Nits.

So when taking that variation into account, when comparing nits, screen size, and lumens, the formula used should be Lumens = Nits x Screen Area x Pi (3.1416). Screen area is determined by multiplying screen width and height stated in square meters.

The HDR Factor

One "techie" term that has entered the TV mix is HDR.​
HDR (High Dynamic Range) is all the rage amongst TV makers, and there is a good reason for consumers to take notice.

Although 4K has improved resolution, HDR tackles another important factor in both TV and video projectors, light output (luminance).

So the goal of HDR is to support increased light output capability so that displayed images have characteristics that are more like the natural light conditions we experience in the "real world."

Because as a result of HDR implementation, two established technical terms have risen to prominence in TV and video projector promotion: Nits and Lumens.

Although the term Lumens has been a mainstay of video projector marketing for some years, when shopping for a TV, consumers are now being hit with the term Nits by TV makers and persuasive salespersons.

So before HDR was available when consumers shopped for a TV, one brand/model may have looked "brighter" than another, but that difference wasn't really quantified, you just had to eyeball it.

With HDR offered on an increasing number of TVs, light output (notice I did not say brightness, which will be discussed later) is quantified in Nits — more Nits, means a TV can output more light, with the primary purpose to support HDR — either with compatible content or a generic HDR effect generated via a TV's internal processing.


Projection/Screen Distance, Seating Position, and Screen Size

The type of lens used by the projector, as well as the projector-to-screen distance, determines how large an image can be projected on the screen, while the viewer seating position determines the optimum viewing distance.

The lens type of the video projector being considered also determines how large an image can be projected from a given distance. This is referred to as a projector's Throw Ratio. Some projectors require a large distance, while others can be placed very close to the screen.

User manuals include specific charts and diagrams that show what size image a projector can produce, given a specific distance from the screen. Some manufacturers also provide this same information on their websites (check the Panasonic example below), which can be consulted before purchasing a video projector.

Video Projector Characteristics Charts

Viewing Distance Calculator


Screen Material, Gain, Viewing Angle

So video projection screens are made to reflect as much light as possible to produce a bright image in a specific type of environment.

So to accomplish this, screens are made of various materials. 

Because the type of screen material used determines the Screen Gain and viewing angle characteristics of the screen.

Also, another type of projection screen in use is the Black Diamond from Screen Innovations.

This type of screen actually has a black surface (analogous to black screens on TVs — however, the material is different).