Adjusting the JVC DLA-RS2's zoom and focus

Posted on December 25, 2007 by Art Feierman

Since JVC chose to use the same remote control for the RS2 as the RS1, the addition of power zoom and focus on the RS2, meant that there is no button on the remote that could be defined for those functions. Instead, press the Test button, select the green grid test pattern, and then hold down the left arrow key, and a FOCUS box will appear in the middle of the screen. (It only works with that test pattern, not the others. The up and down arrow keys let you focus. To adjust the zoom lens, then press the Enter button, which will toggle you back and forth between focus and zoom. Hitting the Exit button takes you back to normal viewing.

JVC DLA-RS2 Lens Throw and Lens Shift

The motorized zoom lens on the RS2 is quoted as having a 2:1 ratio. The actual lens throw chart in the manual indicates that the ratio is actually just slightly more than that. Officially, here are the numbers for a 16:9 100" diagonal screen. Based on this info, you should be able to calculate the placement range for any sized screen.

For the 100" 16:9 diagonal screen, the lens can be as close as 9 feet 10 inches, or as far back as 19 feet 11 inches.

The amount of lens shift is greater than most, quoted as being 80% vertical and 34% horizontal. As with almost all projectors with lens shift, the two affect each other. If you use most of 80% vertical, you are limit, the amount of horizontal shift, and vice versa.

What does 80% mean? The center point would be having the lens at the same height as the center of the screen. The adjustment would allow you to move the image or down the same amount. Let's assume that 100" diagonal screen. It would be approximately 49.3" high - but I'll round to 50" for simplicity. 80% of 50 inches would be 40 inches. The center point is at 25 inches, so up 40 inches would have the lens 15 inches above the top of the 100" screen, or as low as 15 inches below the bottom. That 100" screen would be 87 inches wide, so 34% of that would be about 27 inches either side of dead center, as the furthest off center - if you are not using the vertical lens shift at all. The manual has a chart to show you how they affect each other.

JVC RS2 SDE and Rainbow Effect, Pixel Visibility

ust about as good as things get. There is no rainbow effect - which is caused by the spinning color wheel in single chip DLP projectors. The JVC is a three chip LCoS, and therefore there is no color wheel, so, the Rainbow Effect is not even a relevant issue. SDE, or screen door effect, is the patterning caused by the fixed pixels of the projector, creating a pattern with the data being viewed. This has long been described as like viewing through a screen door. The larger the pixel size, the more likely. First, as a 1080 resolution home theater projector, the pixel size is very small, but more importantly LCoS projectors including the JVC RS-2, start with the least visible pixel structures of the three major types LCD, DLP and LCoS. As a result, the pixel structure is completely invisible at even the closest acceptable seating distance, and screen door effect is non-existan