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I just upgraded from a DLP projector to a Sony G70 CRT. Man, what an improvement, but that’s another story…
However, one of the downsides of CRT ownership (as ya’ll know) is having to perform convergence (registration in Sony parlance) when you first install it.
The most difficult and time consuming (after focus
) alignments is getting the green gun geometry perfect. Usually it involves lots of measuring at the screen. A real PITA in my book…
Since I kept my DLP projector in its ceiling mount location and the CRT is floor mounted, I had a cool idea for how to leverage one to help setup the other.
So, here’s a tip for those of you with CRT FPTV’s and access to a LCD or DLP projector:
Use the AVIA test patterns on the DLP proj. to deliver the crosshatch with dots image at 30 IRE onto the screen. Make sure it’s well aligned (i.e. centered), and with correct keystone.
Then go through a serviceman mode Green gun geometry alignment on your CRT, lining up with the projected gray hatch patterns already on the screen.
The geometrically perfect DLP image lets you easily see bows and skews that measurements might not easily detect. And more importantly, linearity errors are also very easy to spot and correct.
Presto! Perfect green geometry to work from for the R and B guns.
Setting 16:9 ‘picture size’ vertical squeeze is also easy: just switch to the 1.78 letterbox hatch on the system driving the DLP and resize the image on the CRT to fit.
I now have an amazing, perfectly aligned image from my G70.
Try it; you’ll like the results.
However, one of the downsides of CRT ownership (as ya’ll know) is having to perform convergence (registration in Sony parlance) when you first install it.
The most difficult and time consuming (after focus
Since I kept my DLP projector in its ceiling mount location and the CRT is floor mounted, I had a cool idea for how to leverage one to help setup the other.
So, here’s a tip for those of you with CRT FPTV’s and access to a LCD or DLP projector:
Use the AVIA test patterns on the DLP proj. to deliver the crosshatch with dots image at 30 IRE onto the screen. Make sure it’s well aligned (i.e. centered), and with correct keystone.
Then go through a serviceman mode Green gun geometry alignment on your CRT, lining up with the projected gray hatch patterns already on the screen.
The geometrically perfect DLP image lets you easily see bows and skews that measurements might not easily detect. And more importantly, linearity errors are also very easy to spot and correct.
Presto! Perfect green geometry to work from for the R and B guns.
Setting 16:9 ‘picture size’ vertical squeeze is also easy: just switch to the 1.78 letterbox hatch on the system driving the DLP and resize the image on the CRT to fit.
I now have an amazing, perfectly aligned image from my G70.
Try it; you’ll like the results.