Projector lamp life and brightness

[vertigo]

Can someone please advise me on lamp life of projectors?
Specs say they're 2000 hours for example.
1) What happens after the lamp life ends?
2) Does it just go kaput or does the image get progressively worse over time with a drastic downturn after the rough shelf life of the lamp?
3) Why does it happen?

Also re the brightness.
4) What's the ideal minimum I should look for to view with the curtains open during the day? Mostly I'll be working during the day so only using at night, but it's nice to know I'm not going to buy a 3 candle effort.

I'd really like one that supports 1280*1024 although 1024*768 would be fine. My budget is about £250 for a new one and should support PC connection and preferably also RGB SCART and maybe even DVI or whatever the Wii and X360 output (not sure, haven't been paying attention). But I'd just be happy to pick up a really cheap bargain that only supported PC connection and S-Video anyway.

One other thing, if in a dark room, how good are projectors at displaying computer text at resolutions such as 1024*768? Is the text properly legible from the other side of the room? For example if I wanted to relax on the sofa and work on the wall instead of sitting at a desk with a monitor, is this feasible?

Cheers!

[fallenangle]

I can answer the first 3 only. The figure quoted about lamp life are likely to be an average based on extensive but simulated real life testing. They're no more than estimates but from reputable manufacturers probably bias towards minimum expected life. However even if you exclude manufacturing variations, they're likely to be unreliable simply because your specific usage and conditions may vary considerably.

Extreme example: many photographic enlargers are fitted with projector lamps but when used for this purpose, which of necessity involves many on/off switch cycles, lamp life, in my considerable experience, is reduced by at least 50%.

As the lamp ages the brightness and colour temperature will certainly change. It will also change from day to day unless the electricity supply is properly stabilized. I'd expect a good projector to have a voltage stabiliser built in anyway. But whatever the case brightness/col.temp. variations won't normally be visually detectable except perhaps just before the lamp is about to blow.

However, usage conditions could come into play particularly if the room regularly hosts heavy smokers. The image may become considerably more yellow over time as airborne tar etc slowly coats the lamp envelope.

As I understand it lamp life is determined by thermal stress ie. the number of times the filament is heated/cooled and the temperature range involved. There are other factors too like mechanical stress ie. vibration or heavy knocks especially when the lamp is on. Grease from fingers on the lamp envelope when fitting it are also alleged to affect lamp life. So if you are given a tool to fit a new lamp make sure you use it or handle the lamp carefully preferably with cotton gloves on during any replacement.

Having said all this if a reputable manufacturer states 2000 hrs life when used in a digital projector and nothing out of the ordinary occurs during its use I'd be surprised (and annoyed) if it didn't last at least that long. It could last much longer, it's certainly won't commit suicide after that point and should give good or at least acceptable service until it does die. And when this happens, if that is what you're worried about, it shouldn't be in a shower of glass and white hot metal, the filament will just burn out with no more than phut.

NB. My experience only relates to tungsten-halogen lamps not metal halide lamps used in some projectors. My own research suggest the latter although far more expensive are preferable because the col.temp is more stable and they have a considerably longer life.

[vertigo]

Thanks for this detailed answer, very interesting and I suppose in a way it's just like quoted life span of light bulbs, sometimes they last ages, sometimes they blow, but in this case there are certain steps you can take to care for it.
Definitely no smoking in my house so that's not a factor and I'm usually very careful with my electronics anyway.
I suppose it's lucky Capcom don't make a Capcom Projector System 2 or it'd be exactly 2000 hours and you'd have to run it for 500 hours to make all of its features available

Another question: Do projectors suffer any unnecessary stresses when placed vertically when not designed to do so, like CRT TVs can? I'm thinking of being able to switch between use for general PC projection and horizontal and vertical games and fixing the projector with something like heavy bookends or possibly even if there are projectors where the lens/lcd section can be rotated if that exists?

Also, you say that a lamp's life can depend on usage. Are short uses preferred or is it ok to run it for say a 6 hour gaming session without it getting upset, or would I need to make sure it's properly cooled? And do LCD projectors suffer less from heat than your standard DLP?

[fallenangle]

Can't answer most of that but as I said thermal stress is the main lamp killer so you should try to avoid turning it on/off too many times.

Obviously whatever you do the lamp has a finite life, the thermal stress caused when turning it on/off is, I suppose, akin to an age accelerator. I really don't know what the ideal strategy would be to balance those two elements correctly to ensure maximum lamp life. So much depends on how you use the equipment.

I think you just need to believe the manufacturers figures are going to be roughly accurate but by treating the lamp with respect you're going to maximise whatever life it does have.


I've since done some web searching and found a useful page:

http://ask.metafilter.com/56090/LCD-Projector-Bulb-life-when-to-turn-it-off

If you Google you'll find plenty of specific, although often contradictory, expert opinions on digital projector and lamp life..

[vertigo]

Great information, thank you.

Anyone got any input on the whole horizontal/vertical orientation thing?

[nonny]

I dont think there are any projectors out there that allow vertical orientation but then Im not sure why you'd want to.

They are basically monitors at the end of the day so every one I've used (3 so far) allow you to ceiling mount and therefore flip the image upside down. Then you get lens-shift both vertical and horizontal to align it to the screen... obviously the less you use for this the better. Some do this through the menus but some like the one I have (an aging Panny AE700) have a joystick on the front to move the image around with some freedom before you tweak it through smaller increments in the menu.

That allows for wider placement options, plus lens throw differs from projector to projector... some will happily throw out a huge image from only 1-2m away from a wall so suitable for placing on a coffee table in front of you.

www.projectorcentral.com is good for a wealth of information on this.

As for usage. Well you hear some horror stories about lamps blowing way before the expected life hours expire but I must be one of the lucky ones. My Panny AE700 is rated for 3000-5000hrs on low lamp mode and so far I've done a good 3500+. It has dimmed by a good 50% but then my lounge is well light controlled with timber shutters so I can shutout almost all the ambient light if I need to or angle it upwards towards the ceiling and away from the screen itself.

Best place I've seen for purchasing lamps is www.pricejapan.com, a replacement lamp for mine is half the price I would pay locally (here in Australia anyway). If you're in the market for a projector my best advice would be to research like crazy beforehand and narrow down your choices to 1-3 projectors before working out whats right for you. Budget obviously pays a big part in it but I would definitely factor in a screen if you can as it makes a huge difference. Mine was only $400au and the difference between displaying on it and a white wall is day/night. I actually only bought the screen after having my projector for over a year and having seen the difference I wish I had bought one earlier.

Im currently now looking to upgrade to a 1080p model but Im sitting it out for another year until they are really cheap and basically improved on earlier models. Best one I've seen first hand though is the Epson TW2000. Wicked piece of kit that one!

[nonny]

Sorry just to add:

If you're going on the cheaper end of projectors in general at least try and get a 720P native one if you plan to use the Xbox360 or any other HD capable console for games. I used to own an Infocus X1 which could still do 720p/1080i but its nowhere near as good as a 720P native model. At the end of the day if you're feeding the thing an input in its native resolution its going to look all the better for it.

For PC connections its totally feasible to work on the projector display if you want to go that way. I output to mine using a laptop on occasion and just sit there on the sofa working with no issues. The text is perfectly readable on the big screen but as I said above, sending it the right resolution or as close to it as you can is the key to a good crisp image. That and a good display surface!