[Jonathan S]

When I bought my Panasonic AE100E PJ in 2002, I noticed some colour uniformity problems fairly soon - a large red/purplish patch on the left of the screen, green on the right, blue at the top. Most of the material I watch is black & white, which made it more obvious. A Panasonic technician at the time told me "a slight discolouration is normal" on black & white images, so I decided it was something I had to live with, and I have - more or less.

However, after 2000 hours of use (on low lamp) I find there is an increasing yellow tinge across the entire horizontal length of the top of the image, and now a similar blue strip has appeared across the bottom. (It may be coincidence but I only noticed this blue one yesterday after turning the projector upside-down - very gently and not after use - for the latest air filter clean.) I find these strips of unwanted colour more distracting than the discolouration patches mentioned above.

I've found some posts that seem to relate to these issues (mainly the large patch colour problem), but most are very old, and I wonder if there is now a consensus about these problems, or how other owners have cured them?

Are they two separate problems?
Is the horizontal strip colour problem likely to worsen?
Would replacing the lamp help?
Is it worth having the PJ repaired? (It's no longer under guarantee.)
If I buy another projector, am I likely to find a similar problem on viewing black & white films?
Any other suggestions for a non-technical person!?

Many thanks

Jonathan

[cyberheater]

Are they two separate problems?

Sounds to me like a issue with your LCD panels. I think it might be due to heat soak. Someone with more experience with LCD should chime in here...

Is the horizontal strip colour problem likely to worsen?

if it's heat soak then yes.

Would replacing the lamp help?

No

Is it worth having the PJ repaired? (It's no longer under guarantee.)

No. For the cost of repair (at least 300-400 quid) you'd be better of putting the money towards a new machine.

If I buy another projector, am I likely to find a similar problem on viewing black & white films?

All LCD's have a possible issue with this problem. Have you looked at DLP technology.

[theritz]

The colour uniformity issue you've had all along is not related to the recent change in the image projected. This is most likely caused by the Blue Polariser breaking down - heat isn't the cause,afaik, it's got more to do with the amount of UV light that's hitting it and the resultant effect on the coating on the polariser. The blue polariser for an AE100 is about £100, you could order the part from Panasonic and fit it yourself - there are clear instructions in the AE100 Service Manual (I'm sure I have it on my home PC and will email it to you if you like) - it's not brain surgery. I changed mine and it restored the colour very well, although there hadn't been deterioration in mine to the extent that you describe.

Alternatively you could contact Panasonic or Elitevisuals (Click Here who could probably do the job for you.

If you were intending to change the projector anyway, the prospective cost of a new lamp + the cost of repair could well be the guts of the price of, say, a Benq 5120 - you'd want to see a DLP projector first, but it's unlikely that it would have the same colour uniformity (green tinge one side, red/magenta tinge the other) - there's lots of new 5120 owners on the forum, plenty of opinions to draw on.


S.

[cyberheater]

Trying not to get this into a LCD vs DLP debate but i've read from time to time that LCD panels do not stand up well to long term use.

Is this due to older tech and modern LCD machines are unaffected or is DLP DMD panel much more problem free.

[theritz]

cyberheater,

considering your sig,

Trying not to get this into a LCD vs DLP debate

is funny.......

The following from Calibos, king of the high run-times..........

I've done 8900hrs (5000hrs on first bulb and 3900 so far on second) on my AE300(June 2003) Lcd projector and after a thorough cleaning the other day the picture looks as good as the day I got it. I run mine in Low Lamp/High fan though.

............ but there's plenty of people who have different experiences. In the context of 2500 hours runtime, I regard thoroughly cleaning a projector and changing a polariser as no more than "servicing", no doubt others wouldn't see it quite the same way. I have no doubt that cleaning the colourwheel in a DLP projector would be the nearest equivalent, and have seen accounts here and elsewhere of the benefits of doing so. I have seen some suggestion that more recent models have polrisers with caoting which are not prone to the same level of degradation, but have no personal experience - Calibos run-time on an AE300 would suggest that the polariser is holding up well.

The two technologies are different and each has benefits and drawbacks. Potential purchasers would do well to see each in action and vote with their wallets. As far as longevity is concerned, in general people tend to upgrade before the issue arises, and the most common long-term issue with LCD is fixable in about 15 mins. It shouldn't take much longer to clean the colour wheel on a DLP (assuming it's necessary...)

S.

[cyberheater]

I do think that LCD technology will get to the point (hopefully next gen) that it makes DLP redundant.

I'm always bit nervous having a mechanical wheel spinning for hours on end although have never heard of anyones wheel motor dying on them.

Going totally off tangent here.

I'm surprised that there are no laser projectors.

I would imagine a laser capable of covering a visual colour spectrum with enough modulation granularity sweeping across a screen fast enough would offer quite an impressive picture.

Maybe I should invent one

[originalbadboy]

The problem with a laser projector though is that the beams would be so powerful, that if you were to look into it accidently it would probably burn your retina off!

Either that or you would need a diamond coated screen to withstand the heat of a laser ......

On a serious note... It is general consensous that LCD projectors should not be on for more than 6 or so hours, otherwise heat soaking can be a problem. Personally I have never run my PJ's for anything more than 5 hours.

In my expereince of panasonic Pj's, after some use the pure 'whiteness' of the image does degrade to a certain degree, even my AE700, after only around 300 hours of use has started to look every so slightly yellow. (And I do mean ever so slightly, to the point where I may be just imagining it!) Probably being caused by a combination of dust, lamp usage, etc ...

[Mr.D]

No safety issues with lasers . they wouldn't be high powered enough even if you did look into the lens.

Problem is brightness ..that single laser dot per channels has to write the image to the screen fast enough to keep up with the frame refresh rate ..end result ...faster the laser scans the duller the image.

Also visible lasers are expensive ( especially blue ones) and wear out over time.

Laser projection doesn't have anything to offer over current display technologies and there will be considerable problems with colour balancing and even modulating the luminence of a laser system. ( lasers either energise or they are off they don't modulate too well and that means you have to modulate luminance based on beem travel rate and or have them pulse : imagine watching that .

Its a gimmick. The russians gave up on it a few years back.

[cyberheater]

Which is a shame.

It's okay though. LED's will save us

[tonyburns]

hi theritz
ive got a ae200 pany myself 1200 hours on the lamp its 2 years old
the bitch had a dead pixel they wouldnt take it back the bitches techtronics
it was brand new yet it came with no remote i had to pester them for about 2 weeks until i got the damm remote
anyway ive see u changed the lamp how easy was that to do any tips where did u buy your lamp
thanks