:: PICTURE QUALITY ::
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

## Resolution ##
Always look at the native resolution - this is the chip’s actual number of pixel, not to be confused with scaled resolution esp wrt computer signal handling.

HT Perspective: Consideration for High Definition video should be min 720p/1080i, 1080p is preferred. DVD rez is only 480p (NTSC) or 576p (PAL) and that already looks pretty stunning on my 720p projector on a 100″ screen. Thus, for HD to be of significant importance, it will take another 2-3 years when Blue-ray and HD-DVD becomes main stream. Hollywood would most likely try to milk consumers with re-release of old movies in the new HD disc format which is IMHO bullshit. Even on DVD some of the old stuff don’t look anywhere near the newer stuff… is it an issue in the transfer process or inherent in the source?
HTPC Perspective: The current connectors are still DVI vs HDMI in the electronics world. Thus, you’d need a DVI-HDMI cable… on the HTPC side, it would be preferred to get a graphic card that can display in 720p and 1080p resolution.
## Screen Door Effect (SDE) ##
- this refers to the visibility of lines between pixel. Most apparent in LCD projectors and largely reduced in DLP. ** update 15/12/2005 :: new models of LCD has address this to some extend that it should be comparable to DLP

## Rainbow Effect ##
- DLP only. Due to the rotating color wheel.. this is the result of break-up of the inter-changing color as projected. It may also cause eyestrain and headache. Color wheel speed of >4X should be a min (1X refers to 60Hz). This is avoided in proj that uses 3 chips, one for each color.

## LCD Image Degradtion ##
This is a clear possibility but it not conclusive as when it will set in. Test by TI shows the Blue light panel degrades which resulted in color shifts. This is as of 2004 results. I would take such comments with a pinch of salt since it is coming from the inventor of DLP :D.

## Contrast: Shadow Detail ##
How much details can be differentiate in dark scenes; i.e. cave, night scene etc. This is largely a measure of contrast; a value of 2000:1 will give sufficiently good low light detail. DLP better than LCD in general.

## Black Level ##
- how ‘black’ it can get. DLP is generally better in this area where LCD tend to give more washed out look.

## Color Saturation ##
LCD is better, DLP not as “rich” due to white/clear color segment. Improvement in this area is the use of 5/6 segment color wheel and totally eliminate the clear segment at the expense of brightness (lumens).

## Brightness ##
Measured in lumens… 100-200 difference is hard to detect by the human eye due to the auto-compensation nature of the human iris (i.e. open in darker environment and contract in bright light). LCD is traditionally better.

How bright largely depends on 2 things:
1 - How big is the projected image. The bigger, the dimmer is the image for any fix lumens.
2 - How much ambient light. The brighter the room, the higher required lumens for an acceptable image.

<1000
Dark to dimly lit rooms. Size <70″

1000-2000
Moderate to dim rooms. Screen up to 120″.
This is the current mid-high HT projectors.

>2000
Conference and big venues.

## Sharpness ##
LCD is sharper in data presentation, not really visible in video feed. This is a general observation.

:: FUNCTIONALITY ::
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

## Zoom & Throw Distance ##
Throw distance in the base determination factor on how far away the proj need to be from the wall to throw a specified image size. Long throw distances is an issue for small rooms, like wise short throw dist if you like to hide the projector at the back of the room.
Zoom factor will allow fine tuning once the projector position is set - without this facility, size the projected image would means physically moving the unit forward/backward.

## Vertical Offset ##
Most projector will throw an image with some offset from the horizontal. This may be an issue for ceiling mount where there ceiling height is low.

## Lens Shift ##
This allow the shifting of the projected image without physically moving the projector unit. Normally found in more expensive units, could be vertical or horizontal or both.

## Noise Level ##
For HT application, max 30dB. This is of concern if projector location is too near to the sitting position, its prominence especially glaring during quiet passages.