Does anyone know what the factory setting is for Color Wheel Index 50Hz and 60Hz?

In my notes I have the comment from someone that they set it to 21 and 22 to reduce dithering and give a sharper picture, but now on sky scenes I have posterization. You know, sharp gradations between varying colors.

Seems like my former settings were in the 80's, but when I increase them now all the colors go screwy. Around 21 & 22 colors look great, but this posterization. I've done a Factory Reset, but it hasn't fixed it. I think you're not supposed to do a Factory Reset, but can't remember why? What is the Color Wheel Index?

Also, in Guitarman's settings he indicates changing the Second User Area. I know how to get into the Service Menu, but can't find the Second User Area?

Does anyone know what the factory setting is for Color Wheel Index 50Hz and 60Hz?

They all are individually adjusted, so there's no guarantee that values from someone elses machine will work in your pj. I checked my notes from three different machines and values were 25/26, 32/32 and 31/31 (50/60Hz).


In my notes I have the comment from someone that they set it to 21 and 22 to reduce dithering and give a sharper picture, but now on sky scenes I have posterization. You know, sharp gradations between varying colors.


There seems to be some posterization in some scenes (especially bluish scenes) when using DVI-input, but it is gone with component input. Source can be one reason for this of course.


Also, in Guitarman's settings he indicates changing the Second User Area. I know how to get into the Service Menu, but can't find the Second User Area?
I think he is referring to white balance settings in the service menu or ADC settings. As far as I know there's only one service menu.

Thank you, Big Lebowski.

Oh no, CWI individually adjusted. People should not have put this in the suggested tweaks then. I seem to remember mine were originally around 80 & 84, but when I crank them up there now, colors go muddy reddish. Oh well, hopefully this is just a color setting and not an operational setting which could do damage. Colors are fine now.

As to posterization, I am using HDMI, so same-same. Good to know its inherent to digital. I'd never noticed it before I put in the brighter lamp, but fortunately it happens only infrequently, on sky scenes. I'm betting it happens because the D to A converter is not wide enough. (not enough numbers for this level of rez)

Can you discern a ~30 Hz flicker at all, in light areas? With the brighter lamp I would describe it as having a 50% duty-cycle, dimming by 30% alternately, but only in the brightest areas, about 20% of viewing time. I never noticed this with the factory lamp, but maybe it was there.

I had four different units and the CWI ranged from 25 to 30. The easy way to adjust it is to put a full gray field and look for the posterizatiion in the gray field. Then starting from 24 adjust it slowly up until it disappears or pick the best adjustment. This worked really well for me.

Ah, thank goodness, a means to fix it.

Seems like the only way to put up a gray field is to attach a computer and run Avia? Should that be a mild gray gradient, so you can see posterization? Is there another way to get up a gray field? (my computer has a thousand wires, and is in a room across the house)

Being in the US, do I care about 50Hz? Or is this not line-in freq?

What is the Color Wheel Index?
On every color wheel system (FP and RPTV), there is mark of some sort on or in the wheel. This is the color wheel index (CWI) mark. Elsewhere, there is a sensor that "sees" this mark once per revolution and passes a signal to the light engine. There is software in the light engine that keeps the wheel spinning at some multiplication factor of the displayed video by tweeking the color wheel motor controller. The idea is to keep the CWI mark signal at a specific time relationship to the vertical sync signal. Many of these CWI marks are applied to the color wheel by hand during color wheel manufacturing. As such, two specific CWI marks on two specific wheels may not be in the same location with respect to the color segments of the wheels.

The CWI adjustment allows the people in the factory to do fine adjustments to set the timing of the color segments of the wheel with the timing of the display video. That is, it allows them to adjust for someone putting the CWI mark in a slightly different location.

As Big Lebowski said, this is not (normally) a setting that can be shared between projectors. However, setting a "wrong" value should not cause damage to the light engine. It should only mess up the colors.

Ah, thank goodness, a means to fix it.

Seems like the only way to put up a gray field is to attach a computer and run Avia? Should that be a mild gray gradient, so you can see posterization? Is there another way to get up a gray field? (my computer has a thousand wires, and is in a room across the house)

Being in the US, do I care about 50Hz? Or is this not line-in freq?

You can use avia, getgray's disc, dve or even a nice evening sky scene on some dvd if it is gradient enough. These should all be playable via your DVD player. The better the reference, you know you've got a good reliable source.
Good luck.

I seem to remember mine were originally around 80 & 84, but when I crank them up there now, colors go muddy reddish. Oh well, hopefully this is just a color setting and not an operational setting which could do damage. Colors are fine now.

I've seen many peoples reporting their CWI values for this particular PJ but I have never seen anyone else reporting such a high default value as you do.
So maybe it is just your memory playing tricks on you. :)

CWI settings shouldn't do any damage even when adjusted wrong, they just mess the picture when adjusted wrong.


As to posterization, I am using HDMI, so same-same. Good to know its inherent to digital. I'd never noticed it before I put in the brighter lamp, but fortunately it happens only infrequently, on sky scenes. I'm betting it happens because the D to A converter is not wide enough. (not enough numbers for this level of rez)

Same here, quite infrequent. Probably has something to do with DVI being only 8 bit, so rounding errors can occur easily, and it is not just display device that is guilty but source as well.


Can you discern a ~30 Hz flicker at all, in light areas? With the brighter lamp I would describe it as having a 50% duty-cycle, dimming by 30% alternately, but only in the brightest areas, about 20% of viewing time. I never noticed this with the factory lamp, but maybe it was there.
No, I haven't seen that. I quite recently replaced a new bulb and still no flicker in the light areas. Only flicker I see is that during warm up but it goes away just in few seconds.


Being in the US, do I care about 50Hz? Or is this not line-in freq?

I believe this has something to do with the input signal type. So 50Hz is for PAL and 60Hz is for NTSC.


About how to set CWI, I concur what MichaelZ said about using the gray scale.

Of course you can try to fine tune CWI with problematic scenes after you have set it right using gray scale method, but doing so may just worsen the problem in the other scenes. Usually there has to be made some compromises.

Thanks peoples. I've set CWI to 31/31, and posterization is essentially gone. My memory may well have been playing tricks; wouldn't be the first time. Can't pop in Avia, because I do not have a DVD on the TV, only on the computer which is on the other side of the house.

Also I have to look very hard now to see any sign of the flicker. Maybe the flicker is not my new lamp system at all, but was due to my maladjustment of CWI.

Your explanation of the Color Wheel Index makes sense Huckster, thanks.

After much experimentation with Color Wheel Index, I've decided that mine came from the factory as 30/34, rather than 80/84 as I'd remembered. No more general posterization, but still have video artifacts as follows, and I don't have enough technical information to figure it out.

These are noticeable about 10% of the time. Watched "Alive" in the Andes Mountains last night, and I still have a 30 Hz flicker, but only on bright scenes; I'd describe it as having a 50% duty-cycle, alternating between full bright and 10% dimmer. Also in whiter-than-white areas I have blatant patching. (attached)

I don't know whether these are because I'd muggered with the Service Menu, or from the nature of the new driver board. The new driver feeds DC to the arc, but that is also modulated with an AC signal for electrode conditioning, which has to be somewhat in sync with the DLP. I've fiddled with most settings in the Service Menu, and can not resolve this.

After much experimentation with Color Wheel Index, I've decided that mine came from the factory as 30/34, rather than 80/84 as I'd remembered. No more general posterization, but still have video artifacts as follows, and I don't have enough technical information to figure it out.

These are noticeable about 10% of the time. Watched "Alive" in the Andes Mountains last night, and I still have a 30 Hz flicker, but only on bright scenes; I'd describe it as having a 50% duty-cycle, alternating between full bright and 10% dimmer. Also in whiter-than-white areas I have blatant patching. (attached)

I don't know whether these are because I'd muggered with the Service Menu, or from the nature of the new driver board. The new driver feeds DC to the arc, but that is also modulated with an AC signal for electrode conditioning, which has to be somewhat in sync with the DLP. I've fiddled with most settings in the Service Menu, and can not resolve this.
Patching looks quite bad. Have you made sure that White Peaking is set to 0? Otherwise it will cause artefact very much like that in your photos.

I remember some peoples here describing similar problem (even when White Peaking was set to 0) but I cannot remember for sure what was the cause for it, I think it might have been power supply or something like that.

White Peaking is zero. I'll look around to see what was found before.

I am starting to put together these three issues as maybe having a common cause: 30 Hz flicker, patching, lamp hotter than it should be.

The latter symptom is known to be caused by malsynchronization between the system and driver board. The modulated arc signal for conditioning electrodes must sum to zero (AC signal positive plus negative), and if they don't it means too much current, too much heat, and shortening of lamp life. It makes sense that the former two are sync issues too. May have a common cause.

There is a sync signal, and three modes it can work in. Maybe this board having come right from the PRC is set for Euro standards, not US. I will look into this when I get time Monday.

If I can find the definitive cause and fix it, then I would feel OK about upgrading others' machines.

OK, I have it confirmed that this is indeed a sync problem... the new driver has different requirements than the old. And the fix is non-trivial, as I'd have to devise a variable delay circuit.

Just don't have time to analyze this as I must make a living. I guess this will stay as it is for now. The picture is just fine AFAIC.

OK, I have it confirmed that this is indeed a sync problem... the new driver has different requirements than the old. And the fix is non-trivial, as I'd have to devise a variable delay circuit.

Just don't have time to analyze this as I must make a living. I guess this will stay as it is for now. The picture is just fine AFAIC.
Just out of curiosity, what is the name of this new lamp tehcnology you installed?