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Adventures in Designer Mode

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Tip from Michael TLV:  "A special thanks goes out to Mike Sauve and Steve Martin for their tireless work on cataloging all those design parameters. Could not have done this without their help.

Figuring that there might be no more mountains to climb with respect to my Toshiba 61" , I wandered back to the designer mode print outs for the Toshiba sets.

The goal was to see just what was needed to customize each input type on the television. The reason for all this, the realization that while the set was pretty much completely calibrated, there were still a few nagging items about the set. I had calibrated the set based on the component interlaced signal, but whenever I fed the RPTV a progressive scan DVD signal, I had to make some significant changes to the brightness (+5), the colour (-8) and tint (-10). All because the progressive scan signal was odd for some reason. Add to that, the S-video input for all my satellite viewing and laserdisc and other viewing now paid a price too. The image was far too bright.

Essentially, I had a fully calibrated mode that I never used. One could see me banging my head against a wall. What was I thinking? So the new task at hand was to optimize each input for a specific duty.

S-video would be optimized strictly for Satellite and Laserdisc.

Component interlaced would, of course, be for DVD, but this input would see little use except during demonstrations of interlaced versus progressive.

Component Progressive would be the DVD input of choice.

And then there was the HDTV mode ... how would I get that one improved especially given the lack of HDTV test patterns. I'll get to this in a second.

So using all the designer notes, I set the baseline colour settings for the TV and rechecked the grayscale to fine tune it a bit. This set up a proper grayscale for composite video signals and the S-video. Gray scale calibration #1 completed.

With this done, I tackled the component interlaced signal path. A quick reading from the colour analyzer showed that the changes to the base line RGB parameters changed the grayscale with this input type. What started around D6500 was now floating around D7500. It was necessary to use the RGB offsets for this mode to establish the second grayscale in the set. Grayscale calibration #2 completed. In some ways, this was like calibrating the colour on a whole new TV except that I was only adjusting the component input RGB offsets this time.

The third task was to get the Component Progressive signal set properly and also tracking a proper grayscale. The VE disc was very handy in getting the various brightness/colour/tint parameters centered on the menu. I used only the Component P parameters this time. Once this was set, it was time to take grayscale readings once again. D7200 ... pretty much across the board. More tweaking with the Component P offsets for RGB this time. Take another grayscale reading and grayscale calibration #3 was now done.

At this point, I went back to check on the S-video input to see if the other changes I was implementing was affecting this input. Relief ... no impact. The grayscale was where I left it.

A quick check on the component i input and it too was pretty much unchanged. Good news.

Now it was onto the final calibration stage ... calbrating the HD input. From this point on, things get weird since i did not have any real usable HD test patterns. I improvised a bit and the final results are questionable for now. I was able to do a bit of calibrating here by using the VE disc and feeding it as an S-video signal into the Starchoice HD decoder. The decoder will upconvert an external source via composite or S-video into 1080i. So for what it was worth, I now had my poor man brightness/colour/tint patterns working in the HD mode. I set the HD specific designer parameters for these three items.

One last time with the colour analyzer on the upconverted grayscale to see how things were looking. Mixed bag, the upconverted signal seemed to be close to D6500 as a result of the tweaking in the component p mode previously. I left well enough alone for now.

Still not quite convinced that the upconverted test patterns matched the real HDTV signal material. I will have to revisit this one day.

So now:

S-video - optimized for Laserdisc/Satellite.
Component i - optimized for DVD
Component p - optimized for DVD
1080i - a quasi optimizaion for now ...

I should note that after I went through this procedure, DVDs playback via S-video looks poor. The colour scheme is all wrong. Satellite and laserdisc look good. Go figure."