Specifications – What to Observe and What to Ignore
Know What to Pay Attention To
There are a lot of specifications you will see when shopping for a display. Here are some to pay attention to:
- Native Resolution – This determines the actual pixel count for the display. HD demands at least 720 lines of resolution, so your HD sets will be designated as 720p, 1080i, or 1080p. There is a format called “Enhanced Definition” that is 480p – while not true HD it can still produce a great-looking picture on a smaller screen or at a proper viewing distance. We recommend sticking with true HD sets at this point – lower prices means there is no reason to compromise here.
- Size and/or Depth – Triple check the size of the display so you are positive it will fit your needs, your AV stand and/or wall space. This is especially important for rear projection models.
- Weight (rear projection) – Rear projection sets can get mighty heavy. Make sure you have furniture that can take the weight.
- Throw Distance (front projection) - For front projection models, the equivalent advice is to verify your throw distance for the particular screen size you’ll need. This is a MUST or you will find yourself watching a picture that either overfills or under-fills your screen.
- Inputs – It’s important to ensure that the display you purchase will support the inputs you require in your system. If you have a high definition DVD player, PS3 and HD DVR, you may need multiple HDMI inputs to get the most your components have to offer – this could definitely steer you towards a different display (or force you to budget a quality ~$250 HDMI switcher).
- ANSI Lumens – For front projection these numbers are getting better and better. I have been pleased to find somewhat consistency in terms of the relative expected light output form a projector given a particular ANSI lumens rating. Try to remember that a higher number is NOT required for most small home theater environments. Higher ANSI lumen ratings are more important for dual use models or if you plan on utilizing the projector for daytime viewing.
- Tuners – If you are planning to use an existing (or even new) antenna to capture local HDTV signals over-the-air (currently the best way to view HDTV since it is uncompressed) you will want at least one ATSC tuner in the television. For cable TV (without a box) you will need an NTSC tuner or QAM tuner (for unencrypted digital cable channels).
Know What to Ignore
Just as there are specifications to pay attention to, there are also specs which don’t matter worth a hill of beans – primarily because they are difficult to trust and are, for the most part, unstandardized:
- Contrast ratio – Take the absolute brightest output the projector can support and divide by the absolute lowest light levels achievable in a completely black room. That’s your typical number given by the CR figure – and it’s not very helpful in determining a good display in a real world situation. Panasonic’s numbers may not be derived the same way as InFocus, Optoma, Sony, Hitachi, Mitsubishi, etc… Not to mention in the last few years they changed how they measure it so that what was once 6000:1, is now 10,000:1. It’s best to ignore this one and move on.
- Noise output – For front projector noise is certainly important, however the methods used to derive the numbers are not, as far as I can determine, a universal standard. With some of the numbers I’ve seen I can only surmise that they were taken from 6-12 feet away, while others seem to be taken within 3 feet of the unit. The best way to tell if a projector will be noisy is to observe reviews of the model while in Cinema lighting/Eco mode or go audition an installed mode at a dealer.
- Velocity Scan Modulation (VSM), Edge Enhancement – Any edge enhancement features typically (not always) affect the picture negatively. Since we’ll likely turn these features off, it’s not important to have them included on a display.
- Fancy Color Correction Systems – Some displays allow the user to select a particular color and tweak it, affecting tint and hue controls. While a neat trick, we avoid these controls and prefer to focus on properly using the straight Picture and RGB Color and Gamma controls.