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Rebuilding the Color Temperature

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Tip from Michael TLV

Here's a blurb Michael TLV wrote up a while back about the sequence to take to rebuild the colour temperature palette on the Toshiba sets. He says "For now, this is a Toshiba specific item since no other set on the market has this flexibility ... in a published form."

"One Small Brick for mankind. Rebuilding my grayscale from the ground up."

On this evening, when I found some time to fine tune the "lens striping" method, I also ended up doing a bit more. Much more.

I decided to reconstruct the entire colour temperature settings for the Toshiba set to optimize it to all uses and input sources. Colour temperature settings that I tackled this evening were:

  • Cool
  • Medium
  • Warm
  • DVD – Component Interlaced (Lightly touched on)
  • DVD – Component Progressive

The goal was to preset all my colour temperature settings to known values. For instance, I wanted the Cool setting to be 8500K, the Medium setting to be 7500K and of course the warm setting to be 6500K. The thought of the Cool setting being out there "somewhere" in blue land did not appeal to me.

So as I started, I first wrote down all my designer mode settings of relevance. I then proceeded to zero out all the setting specific offset items, namely the CO's, the EO's, the 2O's, the DO's, and the WD's. As I would find out eventually, I had to make a few interesting compromises along the way.

The reconstruction of the grayscale has to be done in a certain order because some offsets affect everything while others do not. The order I took was the same as the listing up top. You have to do Cool first. Period. So I selected the Cool setting from the preference menu and began the process. Adjusting the main R/G/B Cuts and R/B Drv gets me to my desired cool setting. What's somewhat odd here is that the initial building of the Cool/Medium/Warm settings was all done based on the S-video input and from the IRE windows on the A Video Standard Laserdisc. I've said once before that test patterns via DVD S-video never seemed to look quite right when applied to normal viewing material like DSS/Cable/DISH/Video Tape. For what ever reason, the Laserdisc version of the same patterns yielded better results so I stuck with that.

The Cool/Medium/Warm were all set up based on Laserdisc test frames.

Up next was the DVD component 480 progressive input signal. The problem with fine tuning this signal specific grayscale was that the WD parameters did not have any Driver offsets. There were only Cut offsets so it limited what could be done to the grayscale. (As in I could only do half of it to any degree of accuracy.) And here comes the first work around. With the 480P signal, I am in need of Driver controls to adjust the bright end of the grayscale, but I don't have any in the WD section so where to find them. Available R/B driver controls are available in the warm setting's EO's and they affect the 480P signal. So these are my driver controls and it results in making the Warm mode on the TV input specific. It is geared to 480P signals.

This screws my original warm mode setting based on Laserdisc test patterns. So now the second work around. I re-adjust the medium temperature setting which gives me all the five cut/driver controls I need. The Medium setting is now 6500K, but it is optimized for Laserdisc and regular non-DVD TV viewing. I'm down to one usable nonstandard colour temp with the Cool setting at 8500K. Medium = LV/DSS/Tape and Warm = DVD 480P

But in the "not thinking far enough ahead department," I am left with one set of free parameters that contain all the cuts and drivers that I need to build one more input specific setting. I can build the Cool setting into the DVD component interlaced setting at 6500K. Why I would do this is beyond me at the moment. But if I choose to go this route, I will have to rebuild both the medium and the warm settings.

Things to remember. When you are rebuilding your colour temperature settings to match components and input sources, work on the Cool setting first and get it over and done with. You are then free to customize either the Warm or the Medium settings to the other desired input sources.

  • Cool first, then
  • Warm or
  • Medium in either order.

I got the distinct pleasure last weekend to "idiot proof" some of my previous calibration work at one of the local home theater shops. I had worked on their Toshiba TW65X81 previously, setting the warm to properly track D6500. But the ever present danger continued to crop its ugly head … and then I got calls saying that the colour palette was messed up.

One has to constantly remind the sales staff that the TV should be in the warm mode. This television is properly calibrated only in the warm mode!! The Cool and Medium modes are not correct … so stop leaving the TV in those modes and telling me the colours are screwed up. Grrr. ;)

So in I came to make all the colour temperature settings the same. Cool = Medium = Warm = 6500K.   It's a big experiment of course and it will most likely mess with whom ever eventually buys the floor model. They will definitely think the TV is broken … once again … and it would be all my fault too.

One additional task on this particular set too … One of the colour settings needed to be optimized for DBS satellite, in this case, Starchoice. Seems optimizing for DVD did not sit well with that material. Everything had a green tinge. The DVD test material could not be used effectively here, so I deferred to the Laserdisc test patterns. It's all fine and dandy to set it up right, but you have to educate along the way. Oh so many to educate …

My relationship with these store fronts has been an on going experiment for myself. While the work speaks for itself, it's the "idiot proofing" that I have to put more effort into and be more conscious of. Without the proper safeguards in place, one moment the image could be the best on the floor and the next, it could be the worse on the floor.

I am reminded of one RPTV set I calibrated a while back at the local mass retailer. Sitting in a sea of 40 RPTV's and Directview television sets that were so much whiter than white; blue beyond compare … one lonely set that looked too green. Why? Because all the blue sets affect the people's colour perception making the correct set the only "wrong" set. Augh!! Bad call, Ripley, bad call. These people are dead Burke!!

Now you know what I am talking about when I say I have to rebuild the colour temperature settings on a particular set."