Thursday, February 14, 2008

Hitachi 51F500 Calibration

Though requests for CRT calibrations are less frequent these days, I always enjoy the unique qualities these TVs possess. I also enjoy the before and after effect. A CRT can really be transformed into a superb and accurate display capable of very high image quality. This TV is very similar to the F510 model but with a more limited user menu. The service menu however has all the same controls available in its extensive ISF mode to achieve a spectacular image.

When I arrived on site, this TV really need some work. Color was quite flat and the image was very soft. I began with a full manual convergence. I displayed the set’s internal grid and worked my way from the center spiraling outwards. This can be tricky because the guns are defocused during this operation. You really have to get up close and personal with the screen to see what you’re doing. It’s a painstaking process but quite necessary. After about 45 minutes, I was finished. The results were immediately apparent. Clarity was greatly improved and some color had returned to the image.

Moving on to the calibration portion; primaries measured very accurately as with most quality CRTs. The service menu allows turning off the individual guns so aligning the decoder was a breeze. Turning off several options in service eliminated the red and green push inherent in these TVs. Black levels were also very stable at all light levels. This TV has an excellent power supply. This is the most important component in any CRT or plasma display. An inferior power supply will allow black levels to change as light output or APL increases. Grayscale unfortunately was nowhere close, even on the Warm color temp setting. It was so blue, several IREs measured beyond the limit of my metering software (18,000K!). Fortunately, this was easy to fix in service. There are 3 color temp memories, high, medium and standard. I adjusted the standard one to D65.

Once the grayscale and decoder were dialed in a final tweak of brightness and contrast brought the image up to a very high standard. One small surprise: the Scan Velocity Modulation control actually made a positive improvement in image clarity. With Sharpness set to 0, the SVM did improve the picture without introducing any ringing. I usually leave these sorts of options turned off but in this case, Hitachi got it right.

We checked out the results with some hi-def satellite and Blu-ray from a Panasonic BD30. Both sources did a super job at rendering 1080i, the set’s native resolution. Blu-ray content was artifact-free and looked simply stunning. Color depth and dynamic range were every bit the equal of the best plasma panels out there. For those wondering, this TV had not been modified in any way. I have encountered some of these units where clients had lined the cabinet with light-absorbing Duvetyne and or removed the screen cover to cut glare. These mods can show an improvement but in the right viewing environment, they are not necessary. My client’s room had good light control so there were no issues with reflections on the screen or stray light entering the cabinet.

My client has owned this TV for 4 years and plans to hang on to it for a few more. With proper maintenance and adjustment, this is a totally reasonable goal. The image quality is top-notch and the TV is well-constructed. I would recommend adjusting convergence every 6 months and follow-up calibrations every 12-18 months to anyone looking to get a few more miles out of one of these TVs. The DVI (HDMI on the 510) connection is HDCP compliant so current HDMI sources will work. If you have one of these displays in good working order, consider an ISF calibration before you toss it out. You might be pleasantly surprised at the results!

Thanks for reading and enjoy the view!

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