I beleive you that this happens with other brands. We have just under 250 projectors, Sony, Mitsubishi,Canon & Philips. The only units with the "Yellowing" problem are the Philips LC4441. We clean the filters on every projector every month as part of a rolling PM system without fail. Our projectos typically run 9/5 and an addtional 5 hours at weekends. In my opinion this makes the units unfit for the purpose for which they were designed/purchased and as such could be subject to litigation?

Hi Folks, Please read this bit first: If you know where I can get a really cheap bulb then this post is moot as I will just buy one. I would also be interested to know roughly what you think the projector is worth without a bulb (it's in perfect condition). You're probably going to think I am mad for even suggesting this but I am toying with the idea of building an external light source for my projector to reduce the cost of lamps. I have a Philips cBright XG2 which is out of production and has just finished it's first lamp (cuts out after about 10 minutes). I went to buy a new one and nearly passed out when I saw that it would set me back £450 at least (I'm in the UK). I pulled the old lamp out and was surprised to see that not only did it look fine but it consisted of nothing but the housing and lamp - I had expected some fancy control circuitry for some reason and that got me thinking. Thought #1: Would it be possible to but a cheaper lamp for another projector make and put it in the current lamp housing? Trouble is I don't know the exact spec of the current lamp (it's 200W) or where to look for it. Thought #2: At the end of the day you just need to shine (a lot of) light through the projector. The bulbs are expensive because they are small and very bright to make the projector mobile. I don't need that mobility so a huge cheap bulb wouldn't be a problem on that front. Assuming that I can make a light box and position mirrors such that the light is shone through as per the normal bulb my only problem would be tricking the projector into coming on without a bulb in place and that is where I am hoping to get some help. I don't think the light box will be that hard to make. I realize that the real bulb produces very white light etc etc. I was thinking of using either low voltage halogen or perhaps short fluorescent tubes as both produce fairly white light and I think a tweak of the color settings on the projector should take care of the rest. Anyway I think I have rambled on for enough for now. I am really interested in getting this working so any ideas will be greatly appreciated. My electronics skills aren't fantastic but I am willing to learn what I need to make this work. Thanks.