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Projector and Home Cinema FAQ's |More reviews|
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Did you see this? If you think a plasma monitor is HOME CINEMA or HOME THEATRE you must go to a really small Cinema!
Is the public being brainwashed? YES.
Some manufacturers are taking the public for a ride with dubious
Your #1 question what does it really mean?
Aspect Ratio
16:9 (1.85:1) = Wide screen 4:3 = Full Screen, Standard TV size 4/3 = 1.33 16/9=1.77
Anamorphic DVDs are specially encoded to include more visual information than standard DVDs. In Anamorphic DVD: the source aspect ratio matches exactly destination aspect ratio (16:9). In Non-Anamorphic DVD: source aspect ratio of movie doesn't match desired aspect ratio, so video size must be changed while quality will be lost.
HDTV and DVD's are 16:9 (Normally) Standard TV, X-Box, IMAX and most music Video are 4:3 If you don't intend to watch any of the trillions of hours of 4:3 programs then there is no problem with a 16:9 projector and 16:9 screen. If like watching the oldies/music videos and playing games as well as HDTV then a good 4:3 projector will do both 4:3 AND 16:9.
Put simply a 16:9 projector has to do a lot of messing around with a 4:3 signal to display it and the results wont be as impressive as a 4:3 unit showing the same material. On the other hand a 4:3 will show a 16:9 with ease and using for example a 100" projector screen the width will be 100" and the height 75% of the normal 4:3 height with a black bar at the top and bottom. Hint: You can roll up your screen so that there is nothing below the bottom bar and you still end up with an image to blow away most any plasma screen in size.
Here's some facts.. How big is a 4:3 image?
Images are to scale. Help choosing a projector here
Some games are now wide screen 16:9 if you're only playing them Did you notice that some images have the [PAUSE] button showing and others don't?
Digital TV is wider than normal TV therefore they are capable of displaying wide screen movies. Images © 2007 Australian Interactive Multimedia "AIM" Pty. Ltd. Est. 1984
Measured in "DB" We haven't yet tested a projector that was as quiet as the claimed reading but most movies have sound.. This may be because in the fine print they are sometimes measured from say 5M away because that's where they think you'll be seated.If you have a dedicated home theater room with no kids running around and you watch mostly classical music concerts then the quieter the better. If you're viewing in the family or lounge room don't get to carried away with the claims as once the sound is at movie volume you'll hardly hear even the noisiest of projectors sold here. A PC is normally noisier than a projector, my Lap Top can make a fantastic racket when the fan kicks in! If the model has two lamp modes run it on the lower mode to reduce noise and extend the lamp life.. Approximate Sound Levels in Decibels:-
Contrast ratio. How black are the blacks? Most projectors are rated in the 300/2000 to 1 contrast ratio, that is to say the blacks are 300 times darker than the white (on a 300:1 model), this means that true black may appear as grayish. Projectors with say 1500:1 contrast ratio look more realistic showing dark subject matter than 300:1. Having said that the difference in performance is provided your room is totally free from light (vary rare) in the real world we have trouble justifying the price hike between a 1000:1 and a 3000:1 projector as the difference is not 3 times better, rather a slight difference that most people may not notice unless the room is dark. Home theater users tends to fall into two areas, the purist who would have a dedicated room that is totally light controlled and the rest of us who may have a projector in the lounge or family room, for the later spending big or worrying too much about contrast ratio is a waste of time and money as any light in the room and it's game over for contrast, in fact I prefer to have some soft ambient lighting as it makes viewing easier on the eyes.
How black does this box look? Even using a 300:1 contrast LCD computer monitor I bet it looks real black. If you turn off ALL lights and achieve total darkness you will see some white in the black, which is the point, how often will you be in a totally dark room? Note: There are two ways to measure contrast ratio (CR) "ANSI" and "Full on/off" be sure your looking at the same type of measurement before making a decision based on numbers, for example the full on/off method will normally be at least 25% more than ANSI. ANSI = The ratio between the average brightness of 8 alternating white rectangles and the average brightness of another 8 alternating black rectangles. The screen is divided into 4 x 4 rectangles, specified by ANSI. Also called "Checkerboard" it's a more realistic way to test a projector than On/Off but not favored because of marketing concerns. ANSI TEST Some manufacturers are taking the public for a ride with dubious Full On/Off = The ratio between the center brightness of all white (Full On) image and the one of all black The contrast - Full On/Off is always larger than Contrast - ANSI. Measurements must be made in a completely dark room. Many DLP models have their CR measured with the white segment of the color wheel turned on. This increases the white measurements. Home theater users may turn the white segment (Presentation mode) off, many projectors turn it off automatically in video mode. You can glean from the above that buying a projector for home theater based on On/Off CR specifications alone may not be a great idea, the ACTUAL usable contrast ratio you end up is lightly to be much lower. Some DLP projectors and Iris controlled models seem to be leaving the way with deceptive advertising. 70mm movie film has a contrast ratio of 1000:1 (often referred to as Dynamic Range) when I was watching a movie at the Cinema the black scenes weren't black, it looked to me like (as far as contrast goes) as if I was watching a 400:1 LCD projector, that is the black seemed about 5% grey so why do you need 2 or 3000:1 contrast ratio digital projector, especially since once you introduce light into a room, any light, the contrast ratio becomes a little academic. Blacks can only be as black as the white screen, if your room is not pitch black the screen will be reflecting some light. The lighter the room the less you need worry about a high contrast ratio. If you were that fussy you would paint your walls black like the cinema.
Home Cinema is now of higher quality than going to the "Real" Cinema and I'm talking about projection systems costing in total under $2000! DLP, DMD vs. LCD and Resolution Digital Micromirror Device / Digital Light Processor The DMD chip is probably the world's most sophisticated light switch. It contains a rectangular array of hinge-mounted microscopic mirrors; each of these micromirrors measures less than one-fifth the width of a human hair, and corresponds to one pixel in a projected image. When a DMD chip is coordinated with a digital video or graphic signal, a light source, and a projection lens, its mirrors can reflect an all-digital image onto a screen or other surface.
XGA or WXGA LCD projectors having more pixels in the same area than a SVGA model suffer much less from the SDE effect. Some LCD models designed for business use while still having a "Screen Door" offer a very powerful image, more like a Plasma Screen at a fraction of the cost, better for the board room than lounge room however.
DLP projectors have a high contrast ratio and make efficient use of light. While DLP technology has some advantages over LCD, it also has drawbacks, especially in a single chip design, (Consumer DLP models and all models on this site) when the DLP mirrors flip they can turn light on or off (1 or 0). the perception of color is created when light from the bulb passes through a Color Wheel, a small rapidly rotating wheel with red, green, and blue windows or colored filters, before it hits the DLP chip. To make red, the light from the chip is turned on (the mirrors flip on in the red part of the image) when the red window in the wheel is aligned with the light path, etc. Sequentially turning on the red and blue for a given pixel makes purple, red and green make yellow, etc. by rapidly flipping the mirrors in synchronization with the color wheel, the projector can make all the colors and shades of gray needed for video images. Where things may fail is when there is motion in the image, or when one blinks or rapidly moves ones eyes quickly between various parts of the image. In these cases, the perceptual integration of the image may break down and one might see rainbows or false flashes of color, in the image. Some individuals have also reported getting headaches after watching single-chip DLP projectors for any length of time. It appears that not all individuals handle this color averaging process equally well. Newer single-chip DLP-based projectors use a higher speed wheel and have 5 or or more segments in the color wheel, thus greatly reducing the likelihood that an individual will perceive these artifacts. Also, Double Data Rate (DDR) DMD chips reduce artifacts even further by updating the information going to each mirror at a faster rate. DLP does cause more eye fatigue
NEW!
In our opinion if you're easily motion sick, have congenital nystagmus or you're very sensitive to flashing lights you may like to do some research into projection/light engines used in digital projection systems. LCD use three-chip use a separate chip for the red, green, and blue colors to simultaneously present the RGB images so that no temporal averaging or integration by the user is necessary. (your brain can relax!) LCD based projectors intended for home use are three-chip projectors. DLP Chip types and resolutions
DLP Chip Types:
Australian HD-TV (1080i = 1080 Active scan lines, interlaced, x 1920 pixels wide) this is a lot of pixels more than twice the amount the yanks use in their 720P HD signals, the pixels will need to be scaled from 1920 x 1080 pixels to your display device's native pixels. How much information in 1080i-HD? Think of it this way, you're moving around the same amount of data as if you'd take 25 pictures using a 2MP digital camera but your displaying all 25 in one second. That's why the compression is so important and why it looks so lousy when it's overdone. I'll ramble about this for a bit.. If you look at the quality of the Channel 9 HD test loop that they were playing all the time till more shows were in HD (so now you hardly ever see the loop) and compare that with the football it's chalk and cheese.
USA's main HD format is 720P that's 720 vertical lines by 1,280 horizontal pixels wide, displayed in progressive format. (It's also 16:9 aspect ratio) this is why so many HD projectors are 1280 x 720 pixels.
Over Compressed image.. PAL DVD's are 720 x 576 Pixels. PAL uses 625 vertical video lines at 25 Frames per second, around 8% of the 625 possible lines may be discarded in conversion from a PAL recording to DVD. Conversion from film should not have the same limitations. (VHS video tape resolution is around 240 horizontal video lines x 576 vertical lines, S-VHS is about double the horizontal resolution of VHS).One line of thinking is for image smoothness is the greater the number of dots, the better the image. Another angel is the less scaling the sharper the image. Scaling from 1080i to 540 pixels is easy it's 50%. Longevity. DLP technology does not use organic compounds. Thus the elements which can be expected to degrade over time under high stress in an LCD projector do not exist in a DLP projector. Therefore when these two technologies are placed side-by-side in an unusually high stress environment the DLP-based products should be more resistant to image shift over time. STOP PRESS The Epson TW1000 and Sanyo PLV Z2000 use a new C2-Fine inorganic LCD engine that does not degrade over time. Some manufactures that were known mostly for DLP models are now using the new EPSON chip in their 1080 models (True HD).. DLP now making LCD why? http://www.dlp.com for more information about the inner workings of DLP. Throw distance. How far or close your projector can be from your screen. The minimum throw distance is a distance which if less causes the image will be out of focus. Having your projector closer to the screen than the minimum throw distance is bad. The maximum throw distance is often limited by the ANSI brightness of the projector, rather than the upper limit of the focus range. If the projector is moved beyond the max throw distance, the projected image will be so large that it will not be sufficiently bright. This is why you can often be OK with a lower ANSI projector with a short throw distance. It's not only the throw distance that determines the brightness of the image, but the size of the image, if the screen width is doubled the brightness declines by a factor of four. Surround Sound. For more detailed information on specific surround sound systems, see our speakers page.
Connections and Cables. "..we also compared Monster Cable GameLink component cables against a set from Mad Catz.." "..we stopped at three different points to compare accuracy and color composition, but we didn't find much of a difference between the cables. If there was a difference, we couldn't find it in our impromptu test. "
SCART
Mounting brackets. See Projection screens. Give that professional look and improve performance over simply projecting onto a painted wall.High Gain screens are available for LCD projectors, normally coated with small glass beads that reflect back more light, often used in rooms with high ambient light levels. See I have a DNP daylight screen at home because I can, it costs a fraction of an 100 inch plasma and in many ways it's better, for a start the screen lasts forever! Running Costs. Projectors use lamps that wear out, most lamps are rated between 2000 and 4000 HR AVERAGE or typical life. A few points to consider: If your lamp blows up at 1900HR and it's a 2000 HR lamp we don't think they will give you a new one. You need to check their policy in this regard. You may need to run the projector in "economy" mode to get the highest yield from the lamp, thankfully this seems to make little difference to the brightness in most models. The lowest running cost models reviewd at time of writing are about 11c/HR How long they actually last. Lamp Life. How long your lamp lasts depends on several factors including:-
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