Flagship Home Theater - Part 1: Anthem LTX-500 LCoS Projector and SI Black Diamond II Screen


Using the Projector's Menu to Calibrate the Image

Calibration of the LTX-500 covers four major areas:  levels, grayscale, gamma, and color management.  I did all my measurements and adjustments in one of the three User modes.  As with any display calibration, adjustment of grayscale, gamma and color management must be done with instruments to achieve accurate results.

When I initially installed the projector, I was unable to see below-black and above-white information output from my Accupel signal generator unless I turned on the Enhanced setting in the Input Signal menu.  After upgrading the firmware, below-black and above white bars were visible in either the Enhanced or Auto modes when I used my Accupel signal generator as the source.  When I tried disc-based patterns from my Panasonic and Denon players I had to turn on the Enhanced mode again to see them.  After viewing a lot of different patterns I settled on -5 for brightness with the lens aperture at -6 out of 15.  Contrast was left at the default.

Grayscale adjustments were up next.  I was able to easily achieve flat grayscale tracking with the RGB high and low controls.  Gain (high) is adjustable with 256 steps but the scale starts at the maximum value.  Therefore you can only reduce colors to make your adjustments.  Offsets (low) have 100 steps of adjustment but start in the center of their range.  The fine gradations are nice and make precision adjustments a snap.

The gamma curve editor is quite ingenious.  You can move the entire curve up and down with the Correction Factor control.  You can also copy and paste one of the preset curves to use as a starting point.  Then you can tweak the gamma to perfection by adjusting each point starting at 5% up to 90%.  If you want to adjust individual points for red, green and blue, that function is available too.  When you’re done, the LTX-500 prompts you to save the data before exiting the gamma screen.

As I said earlier, the Color Management System (CMS) is the best I’ve ever used, after the firmware update.  When I first calibrated the LTX I could only correct the color luminance.  The Hue and Saturation controls did not allow me to bring the color points in to the correct positions on the CIE triangle.  Out-of-the-box, the LTX-500’s color is oversaturated, especially for red and green.  I could not lower the saturation control enough to correct this.  Once the update was installed, I found I had greater range in the saturation control and so was able to bring the colors to the correct positions.  More on this in the Bench Testing section.