Focused Technology Blog

Business Projector Buyer’s Guide

elane — Tue, 05 Aug 2008 10:44:01 +0000

Things to look for when purchasing a conference room projector:

DLP and LCD are the two main types of conference room projectors. While the gaps have been bridged significantly through the years as technology has improved, there are still some basic fundamental differences that you need to consider. Business projectors with DLP technology use a single chip made up of several thousand, sometimes millions of tiny mirrors that reflect light to produce an image. DLP units are typically lighter, with smaller housings than LCD models. LCD requires three LCD panels, which makes for brighter pictures, but more difficult for manufacturers to produce ultralight portable units. It has been claimed that DLP projectors last longer than LCD projectors, but are more expensive.

DLP
DLP (digital light processing) is a proprietary technology developed by Texas Instruments. Business specific DLP models will come with one DLP chip that is made up of several thousand, sometimes millions of tiny mirrors. Each mirror accounts for 1 pixel, or single point of light, in the image. Light from the projector’s lamp is reflected off of the mirrors which either wobble “on” to direct the light towards the lens or “off” directing the light away. Business model DLP projectors use a color wheel to modulate the color of the image. This wheel spins in the light path between the lamp and the DLP chip and the filters determine the color of the light hitting the chip.

Pros: A key advantage is its portability, DLP technology can be used in small, ultralight projectors to enable them to deliver a high fidelity picture that rivals much larger units. In fact, all of the projectors under 3 lbs. on the market today are DLP projectors. If you’re looking for a model that can be carried along easily in your briefcase, DLP would be the best choice. Another advantage is that the distance between each pixel, or inter-pixel gap, is very small on DLP projectors. LCD based projectors typically have wider gaps, making the pixel structure more visible, causing a “screen door” effect.

Cons: One downside is light leakage around the mirrors, which generates a sort of halo on some images. Newer DLP projectors use a “dark” chip, which uses a dark undercoating on the undersides of the mirrors to eliminate this problem. It’s also important to note that some lower end DLP models use lower quality color wheels. Lower quality wheels can not only produce poorer color saturation, but can also produce a “rainbow effect’, which is a visual artifact in the image. Most newer models have a wheel that is 4x speed or faster and will not have any rainbow effects, though some people are more sensitive to it than others. Check the specifications of the color wheel for the model you’re considering.

                                    If a DLP projector is best for your business needs, keep these things in mind at purchase:
                                    Resolution- XGA (at least 1024×768 pixels) or UXGA
                                    Contrast Ratio- 600:1 or greater
                                    Brightness- 1500 lumens or greater
LCD
LCD (liquid crystal display) projectors place three LCD glass panels in the projector, one for red, one for green, and one for blue. Light passes through the panels and individual pixels open or close to produce the image.

Pros: Images are generally brighter, and LCD will produce more saturated colors, which also leads to an image that seems brighter and more vivid overall. LCD images are very sharp and clear. LCD has the upper hand over DLP in terms of the rainbow effect, which is an occasional artifact visible on the DLP screen to some viewers. The rainbow effect does not occur in LCD projectors. Where color reproduction is an important factor, LCD is often the preferred technology. In general, LCD projectors offer excellent performance at a good price. Earlier limitations in terms of pixilation and contrast have been overcome in newer projectors, and LCD projectors can be used effectively in a wide variety of applications.
Cons: In some cases, especially when projecting video, pixilation can be more noticeable with an LCD projector, although with an XGA or higher resolution it is not a problem. The result is a “screendoor” effect, which is caused by the inter-pixel gap. LCD has weaker contrast than DLP projectors, which makes it less desirable for video. Another minor problem with LCD is long term degradation. Tests have shown that over time, some LCD panels will degrade, which will cause a shift in the color balance and reduced contrast. This is especially true in the blue panel. This may lead you to eventually replace the LCD panels in your unit which is costly.

Brightness

To find the right conference room projector for you, first consider your circumstances. Take into consideration how large the room is, how large the projected image must be in order for the audience to see it clearly, and if you want your audience to be able to take notes or refer to written material. Determine the level of brightness you require in a projector. A low lumen projector may cost less, but you will have to project your image in a darkened room. Whereas the higher lumen projectors allow more flexibility. A totally dark or dimly lit room is usually not necessary, but for best screen viewing, presentations should be done with the room lighting somewhat reduced.

Brightness Guide:

            500-1000 lumens = 5′ to 6′ (152cm-183cm) screen in a small room with 5-10 people and no lighting
            1000-1500 lumens = 8′ to 10′ (244cm-305cm) screen in medium room with 10-30 people and dim lighting
            1500-2000 lumens= 12′ to 25′ (366cm-762cm) screen in large room with 30-100 people and window or ambient lighting
            2500 lumens= audience less than 100 people with ambient lighting
            3000 lumens= audience of 100-200 people with ambient lighting
            5000 lumens= audience of 100 or more with bright lighting

DLP vs LCD:
LCD in general is more “light efficient” than DLP. When using the same wattage lamp, the LCD would produce a brighter image than the DLP. With a data signal, if using a 1000 lumen LCD next to a 1200 lumen DLP, most people would probably prefer the LCD for brightness.

Resolution
The resolution of your projector will be the main factor that determines how sharp and clear your picture will be. In general, the higher the resolution the better the quality of picture will be. You will see more detail and it will be less grainy and pixilated. The resolution of the projector should match the resolution of the computer that will be used with it. If you are not planning to display a lot of complicated or detailed graphics, a lower resolution projector will be adequate. The lower the resolution, the more money you will save.
Resolution Guide:
SVGA (800×600 pixels)= basic PowerPoint presentations

XGA (1024×768 pixels)= spreadsheets and displays with columns of numbers

SXGA (1280×1024 pixels)= technical drawings, small details(CAD/CAM applications), and detailed graphics

SXGA+ (1400×1050 pixels)= detailed photography and data graphics

UXGA (1600×1200 pixels)= very detailed

Pros:

            SVGA which is most common is the least expensive
            XGA is adequate for most needs and is very affordable
            SXGA is used where there is need for showing small details
            SXGA+ is available in both budget and high-end configurations
            UXGA is for very high resolution workstation applications that are detailed or information intensive and support a broad range of computer equipment

Cons:

            SVGA is at the low end of the scale and all though still available, are generally being replaced with XGA
            XGA is not adequate for engineering drawings, digital photography, or other images of a highly detailed or technical nature
            SXGA is considerably more expensive
            SXGA+ is overkill for text display or PowerPoint presentations
            UXGA is very expensive

DLP vs LCD:
In general, higher resolution shows more detail and provides a better quality of picture. In some cases with LCD projectors, especially when projecting video, pixelation can be more noticeable, although with an XGA or higher resolution it is not a problem. For the best picture quality with a DLP projectors it is suggested that the XGA or UXGA are best.

Contrast Ratio

Contrast Ratio is the difference between the whitest white and the darkest black colors that the display can show. The higher the contrast the crisper your images, the more vibrant your colors will be, and the better the color representation. When a projector provides good contrast, images are clear and attractive. Projectors with a lower contrast ratio may become difficult to see clearly and tend to appear washed out and faded. Room light substantially impacts contrast ratio.
            Contrast Ratio Guide:
            500:1 or less = low contrast
            500:1 to 1200:1 = medium contrast
            1200:1 or more = high contrast

            Pros:
            In a darkened room, contrast will be important for accurate display of graphics and video. In a room with moderate lighting a 400:1 contrast and a 1500:1 contrast will look almost identical, all other factors being equal.
            Cons:
            In a room with a good deal of ambient light, blacks look less black, so lumen output will be more important than contrast.

DLP vs LCD:

DLP projectors are able to achieve a higher contrast. LCD is often the preferred technology when color reproduction is an important factor, even though they have a weaker contrast than DLP projectors. Regardless, both the DLP and LCD projectors will produce a clear and vivid picture, especially with a higher resolution.

Replacement Projector Lamps / Projector Bulbs

Administrator — Mon, 14 Jan 2008 22:01:55 +0000

Projector bulbs, usually called projector lamps, are one of the few user replaceable projector parts. Unlike a car headlight or standard light bulb, a projector replacement lamp module varies by model. With metal halide lamps, you’ll notice a dimming of the image brightness as the lamp loses power. Projector bulbs typically last about 2,000 hours. Some of the newer projectors offer extended lamp life of 3,000 hours, and a few are up to even as much as 5,000 hours. Keep in mind however that some projector bulbs won’t make it all the way to their estimated life spans. If you operate your projector in a warm environment that is not adequately ventilated, or at higher elevations, this can reduce lamp life. Also, failing to keep the air filter clean may reduce lamp life as well. And some lamps will just fail sooner than others–estimating average lamp life is not an exact science. The main causes of premature lamp failure are excessive heat and inadquate ventilation. Therefore, we recommend the following: 1. Do not unplug your projector from the wall in order to turn it off. Use the remote or keypad on top of the projector to turn off the unit. Let the projector cool down and shut itself off before unplugging and packing up your projector. 2. Clean the air filters on a regular basis. Clean air filters allow the projector to maintain a constant flow of air circulating through the unit and keeps the lamp from overheating. 3. Allow the projector to have adequate air flow. If the projejector is stored on a small enclosed shelf the air flow will be restricted and heat will build up. Allow a minimum of 2 feet on the top and sides of the projector so that air flow can be maintained.

Things to consider before buying a projector

Administrator — Mon, 14 Jan 2008 21:33:17 +0000

1. Resolution - What is the main use for the projector?

If is to show powerpoint presentations for a business, school or church etc. you will typically go with XGA resolution. This is a 4:3 format you see on most computer monitors. If you are on a tight budget you can save $100 or so by downgrading to SVGA resolution but in my opinion the loss in image quality is not worth the savings. Additionally, you can also upgrade to a higher resolution model (SXGA or WXGA) if your presentations contain highly detailed graphics and or wide format images.

If the projector is going to be used for movies and home theater applications then you would typically go with a wide screen format projector (i.e. 16:9 ratio). Note: there are different levels of wide screen format projectors - Low End (854 x 480 pixels), Mid Level (1280 x 720 pixels), High End (1920 x 1080 pixels). The more pixels the better the image and higher the cost.

2. Brightness (measured in lumens) - Again, what is the main use for the projector?

If is to show powerpoint presentations for a business, school or church etc. you need a bright projector. A standard classroom or conference room with some ambient light would need 2000 to 4000 lumens. A church or large auditorium typically needs 5000 or more lumens.

If your projector is for a dedicated home theater that has limited or no ambient lights 1000 to 1500 lumens is typically sufficient.

3. Contrast Ratio - The difference in light intensity between the brightest white and the darkest black. A higher the contrast ratio is better than a lower one.

Medium Contrast (400:1 to 1000:1)

High Contrast (2000:1 and up)

4. Inputs - the connections on projector that enable you to hook it up to other types of equipment (i.e. DVD player, Computer)

If you are doing powerpoint presentations you will need a VGA connection. This is standard on almost all projectors that are not specifically geared towards home theaters.

If you are buying a projector for a home theater you will want to get a projector that has digital video inputs (i.e. HDMI or DVI). These inputs will enable you to watch High Definition Television and DVD’s.

5. Weight - If you plan on taking your projector on the road for mobile presentations you may want to consider a model with a small footprint. Typically, 3-6 pound projectors are preferred.

6. Noise (measured in dB’s).

0 dB is the threshold of hearing

10 dB is barely audible

20-30 dB is a soft whisper (dB levels in this category are usually found on home theater projectors so that projector noise does not interfere with movie experience)

30-40 dB is a whisper or the hum of a refrigerator (most business projectors fall in this range)

40-60 dB is the noise level of rainfall or a normal conversation (some very small projectors and some very large projectors have dB’s in this category, this is due to the fan noise required to keep the unit cool)

7. Warranty - projector warranties typically range from 1 to 3 years. While it is rare that warranty service is needed…it does happen. If you are comparing models with similar specs the projector warranty should be a factor in your final decision.

8. Replacement lamp price. Most replacement bulbs are estimated to last 1500 - 3000 hours (sometimes more…sometimes less). That means that depending upon how much you use your projector you will periodically have to spend ($200-$500) on a new lamp. Once again, when comparing models with similar specs it should be a factor in your final decision.

Da-Lite Projection Screen Fabrics

Administrator — Mon, 14 Jan 2008 19:20:06 +0000

Matte White

One of the most versatile screen surfaces and a good choice for situations when presentation material is being projected and ambient light is controllable. Its surface evenly distributes light over a wide viewing area. Colors remain bright and life-like, with no shifts in hue. Flame retardant and mildew resistant.

Viewing Angle: 60°
Gain: 1.0

High Contrast Matte White

Designed for moderate output DLP and LCD projectors. This screen surface is a great choice when video images are the main source of information being projected and where ambient light is moderately controlled. With its specially designed gray base material and reflective top surface, this screen material is able to provide very good black levels without sacrificing the white level output. Flame retardant and mildew resistant.

Viewing Angle: 50°
Gain: 1.1

Video Spectra™ 1.5

This screen surface is specially designed with a reflective coating, which provides an increased amount of brightness with a moderately reduced viewing angle. The increased gain of this surface makes it suitable for environments where ambient lighting is uncontrollable and a projector with moderate light output is utilized. Flame retardant and mildew resistant.

Viewing Angle: 35°
Gain: 1.5

Silver Matte

A uniquely designed screen surface with a specifically designed silver finish. This surface is perfect for situations where a silver surface is necessary for a polarized 3-D projection. The matte finish of this surface successfully rejects ambient light. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 30°
Gain: 1.3

High Power

A technological breakthrough, providing the reflectivity and optical characteristics of a traditional glass beaded surface with the ability to clean the surface when necessary. Its smooth textured surface provides the highest gain of all front projection screen surfaces with no resolution loss. The moderate viewing angle and its ability to reflect light back along the projection axis make this surface the best choice for situations where there is a moderate amount of ambient light and the projector is placed on a table-top or in the same horizontal viewing plane as the audience. Flame retardant and mildew resistant.

Viewing Angle: 30°
Gain: 2.8

Da-Mat™

A screen surface with a smooth, white vinyl finish for precise image reproduction that provides an exceptionally wide viewing angle and no resolution loss. It is a highly flexible fabric that may be folded or rolled. Its versatility makes it a great choice for situations with good control over ambient light and where an exceptionally wide viewing angle is necessary. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 60°
Gain: 1.0

Cinema Vision

A unique non-supported vinyl fabric that offers a bright, uniform image with no color shift at any viewing angle. This surface is designed to provide a higher amount of brightness for lower output projector types such as CRT. Its increased reflectivity will help enhance the image brightness in situations where a low level of ambient light is present. This surface is a good choice when producing video images. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 45°
Gain: 1.3

Pearlescent

A non-supported vinyl fabric, offering a higher degree of reflectivity and brilliance without loss of image quality or resolution. This surface is a good choice when producing video images with a lower output projector and where there is a high amount of ambient light present. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 40°
Gain: 1.5

Audio Vision

Designed for applications where a more realistic soundstage is desired, this fabric allows for the installation of speakers to be placed behind the surface. With virtually no sound loss and good image quality, this fabric provides the same optical characteristics as the Da-Mat surface with specially designed perforations to allow sound to pass through the screen material. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 50°
Gain: 1.0

High Contrast Da-Mat™

With a special gray surface, this screen material is designed for use with today’s high output LCD, DLP and D-ILA projectors. By lowering the black levels of the projected video image, this surface creates a more film-like image and is a good choice when video is the main source of projected information. This screen surface is best used when there is good control of ambient lighting and a moderately wide viewing angle is desired. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 45°
Gain: 0.8

High Contrast Cinema Vision

Designed for today’s moderate output DLP and LCD projectors, this screen surface is a great choice when video images are the main source of information being projected and where ambient lighting is moderately controlled. With its specially designed gray base surface and a reflective top surface, this screen material is able to provide very good black levels without sacrificing the white level output. With its enhanced black levels and brilliant white levels, this screen surface provides deep life-like colors and greater detail and sharpness to the image. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 50°
Gain: 1.1

High Contrast Audio Vision

With the same optical characteristics as the High Contrast Da-Mat material, this surface is designed to provide the viewer with a more realistic soundstage by placing speakers behind the screen and allowing the sound to be transmitted through the material. This screen surface is best used when there is good control of ambient lighting and a moderately wide viewing angle is desired. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 45°
Gain: 0.8

High Contrast Cinema Perf

With the same optical characteristics as High Contrast Cinema Vision, this surface is perforated to allow placement of a center channel speaker behind the screen surface while allowing the sound to transmit through the material. Ideal for use in environments with moderate control of ambient light. Screen surface can be cleaned with a mild soap and water solution. Flame retardant and mildew resistant.

Viewing Angle: 50°
Gain: 1.1

Silver Vision

This screen surface is uniquely designed with a specially formulated silver finish. This surface is perfect for situations where a silver finish is necessary for polarized 3-D projection. The silver finish of this surface successfully rejects ambient light. It is a highly flexible fabric that must be tensioned. Screen surface can be cleaned with mild soap and water. Flame retardant and mildew resistant.

Viewing Angle: 30°
Gain: 1.5

Buyer’s Remorse. What to know and what to consider.

Administrator — Mon, 24 Dec 2007 16:33:26 +0000

Buyer’s remorse… how do we fight it? Well when it comes to projectors, people are relatively confident in their purchase in the process of buying. But it could be for different reasons. Some people say that,” Instant gratification is key,” and once someone is working up the excitement of buying a projector, they end up forgetting some key aspects that could spell disastrous buyer’s remorse in the future. This is evident with anything you buy obviously, however setting up a home theater isn’t always the easiest of tasks, and once you are ready to get a projector system; whether it is the first time you are considering getting a projection system, or are upgrading your current one, there are many factors that effect your home theater situation.

With the advent of Blu-Ray and HD-DVD, and the already widespread confusion of which to go with, people sometimes forget about taking those two formats into consideration. Back in 1993 MultiMedia Compact Disc and Super Density Disc were in the run to be successors of VHS, and after Sony and Philips had abandoned their MultiMedia Compact Disc for Super Density Disk, “DVD” had been unofficially named in 1995. Now that we have been using DVDs for almost a decade, and VHS being in circulation for about a decade as well (since the ’80s), we are once again in the middle of a format “war.”

Some of you might say,” DVD is not going to die off any time soon, and I already have a large DVD selection so why should I switch to HD-DVD or Blu-Ray? Well, when DVD came out, people were unable to use their VHS movies in DVD players or in one unit that can play both unless you spent more than a thousand dollars. But since we are still using discs for media, the story is different now with the High Def formats. However, unlike DVDs where practicality and enormous differences made the switch from VHS easier to decide upon, the difference with 1080p projectors and moving to a HD movie format has to be seen to be believed. Where the switch from VHS to DVD was features and practicality, the switch from DVD to HD is quality of material. Yes there are new interactive features, and a couple of new additions to the HD formats, but the jump isn’t as significant on the features front. It’s undeniable that either Blu-Ray or HD-DVD will become the standard format in the near future, but the only thing left to decide is, “When should I move to it?”

Well, for most people the logical answer would be to wait until there is only one format. However, if you’re in the market now for a projector; either because your old one has failed, the replacement bulb has become to expensive or unavailable or are considering upgrading their current unit, it would be a good time to consider what it is you should go with. With 1080p projectors now slipping slowly under $2000, it is becoming more feasible to own a 1080p projector. Some may ask why you “need” such a projector. I’m sure we’re all aware that you don’t “need” it. But with HD players becoming cheaper all the time, I would say personally that it is a pretty good time to start “future-proofing” your home cinema experience.

Now, on which format to decide on, that’s a different story…