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Topic: IS FullHD excessive for classroom projectors?
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Joined: Sep 29, 2016
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I manage all of the classroom technology at a small university (60 classrooms.) Each classroom has an installed projector. All the larger companies; Panasonic, Epson, NEC, Hitachi, etc. try to sell me their education/conference room lines, which I find to be laughably anemic in stats, particularly resolution. Why do all of these companies still make XGA resolution projectors!? I haven seen an XGA display since 2009. (All of our classrooms have all-in-one desktops with FullHD displays.) If you want wide screen it's WXGA. What I want to say is "Don't wast my time with anything less than FullHD resolution or better and at least 3500 lumens, preferably more."

Am I being too picky? Demanding? It's almost 2017, I don't want XGA anymore.

Thanks for you're input.
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Joined: Mar 28, 2005
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Schools are often all about budget, above all else.

While I fully agree, that 3,500+ lumens and 1920x1080 resolution is a great minimum standard, the real minimum standard within school systems is money. That's what it all comes down to and what it is.

The other question is whether 3,500 lumens is an appropriate number and if anyone actually cares that they are being lied to by manufacturers.

That is, a 3,500 lumen, cheap DLP projector, is likely to deliver under 1,000 real world color lumens. While a 2,500 lumen LCD projector is likely to deliver over 2,000 real world color lumens.

So, do you want a 3,500 lumen DLP which can't deliver, or a 2,500 lumen LCD which CAN deliver?

To that end, is 2,500 lumens more than you need or less?

What's the solution?

ASK!!!

Don't assume anything if you are going into a major purchasing decision process. Go in with questions, and don't just ask the guy who is trying to sell you something. There are forums, like this one, which can give you some direction.

To that end...

1920x1080, or more often in the commercial space, 1920x1200 resolution projectors are out there in full force and readily available. They have very limited placement flexibility for cheaper models, which is common of most projectors. So, no surprises there.

But, what about the resolution game?

I've gotta say that while 1920x1080/1200 is phenomenal, and shows a ton of detail, the text size which results is often far smaller than many people can read from the back of the classroom. This is something which teachers would need to learn to adjust their presentations to deal with. Still, it's an issue. 1280x800 projectors, while not showing as much detail, actually does a very good job in most rooms to deliver larger text and details which can be read at the back of the room. Either way, the recommendation is for a widescreen resolution, not XGA.

The screen size in many classrooms is smaller than recommended. Many installed screens are still 4:3 aspect ratio, which means new widescreen projectors would take up a smaller portion of an already small screen, in the wrong aspect ratio. For new installations, I would stick with 16:9 or 16:10 aspect ratio (16:9 is what SHOULD be used in my experience). At least 100" diagonal, preferably larger.

Technology: DLP is great, but some people suffer from headaches due to image color separation by the use of a color wheel. This same color wheel also limits the brightness of images with color in them. I would avoid DLP, and their extremely inaccurate lumen claims. Stick with LCD (or LCoS) and the more accurate numbers and quality of the color image you get. It really does deliver far more brightness for the money.

Brightness: About 50 real world lumens per square foot is the minimum required goal for a screen under normal florescent lighting. Typical of most classrooms. On paper, this actually means no less than 80 advertised lumens.

Basic math here: Screen height (inches) x screen width (inches) / 144 x 80.

So, a 120" diagonal screen is about 63" x 102" = 6426 square inches. Divide by 144 = 44.625 square feet. Times 80 lumens = 3,570 lumens minimum.

So, if you do have 120" diagonal screens, then your call for 3,500 lumens is VERY close to accurate. Going brighter will not be a bad thing. 3,500 - 4,500 lumens is great, and will deliver about a 10:1 to 15:1 contrast ratio in a typical classroom.

So, going widescreen, LCD, with 3,400+ lumens, and a price point under $2,000, you have taken a list of hundreds of projectors to a list of just 45 projectors...

http://www.projectorcentral.com/projectors.cfm?g=1&hide=0&st=1&mfg=&p=300&p=2000&w=&r=&br=3400&br=10000&ll=<g=&t=&db=&dt=1.0.0&c=&ar=Wide+%2816%3A9-10%29&dvi=&wr=&pjl=0&pjw=0&pjh=0&td=&is=&i=d&tr=&oop=1&sort=brt&sz=15

We will add one more piece to the mix, and require 1920x1200 resolution...
http://www.projectorcentral.com/projectors.cfm?g=1&hide=0&st=1&mfg=&p=300&p=2000&w=&r=16&br=3400&br=10000&ll=<g=&t=&db=&dt=1.0.0&c=&ar=&dvi=&wr=&pjl=0&pjw=0&pjh=0&td=&is=&i=d&tr=&oop=1&sort=brt&sz=15

That list of 45 models only has 8 which are 1920x1200 resolution.

Why not 1920x1080?
Well, if you search the same criteria, and demand 1920x1080, the resulting list is ZERO. It doesn't matter though, because all these 1920x1200 projectors, as far as I know, have a setting in them that allows you to tell them you are using a 16:9 screen. This way you only use 1920x1080 pixels and 120 pixels are not used.

You will notice that the majority of the 1920x1200 projectors are towards the top of that $2,000 price range which is specified.

But, if I were to come at you with a couple, high resolution, recommendations, then I would go with the lower priced Epson:

http://www.projectorcentral.com/Epson-PowerLite_1980WU.htm

Or the slightly brighter, better built Panasonic

http://www.projectorcentral.com/Panasonic-PT-VZ575NU.htm

The Epson has a lower rated lamp life, and a 2-year warranty.

The Panasonic, for a bit more, adds a fair bit to the lamp life, and has a 3-year warranty to go along with it. It has some lens shift as well, which can help with more tricky installations, and is slightly brighter, which may allow it to run in low-lamp mode more easily, which will help lamps to last longer.

What about lower resolution options?

Well, the trade-off is price. A dozen plus models that are less than the least expensive 1920x1200 models. Epson, Panasonic, Sony, etc. are all in the mix. You also get some ultra short throw models (for interactive whiteboards) if you need them.

There are a ton of other things to discuss in all of this potentially. Most notably, during construction, all classrooms should have two zones of lighting. One towards the back, and one towards the screen. That way you can increase contrast significantly. Less washed out images = easier for everyone to see.

Since I know very little about your actual environment or circumstances, it's very difficult to be dead on, so the knowledge above is very generalized, and not very specific. A situation where you need to outfit half a dozen classrooms and you have a solid budget can dramatically change things. An entire school with 100+ rooms, the price difference between a $1,000 model, or even a $500 model, and a $1,500 model can completely wreck a budget which was established within a vacuum.

It's worth saying that most professional consultants aren't worth the money. They are often lousy and don't think about either your budget or the requirements of the installations.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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Joined: Sep 29, 2016
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Quote (AV_Integrated on Sep 30, 2016 6:06 AM):
Schools are often all about budget, above all else...

Wow, thanks for that informative response. I've been in this position for about 7 years now but you gave me some new things to think about.

I agree with your comment about budget, thankfully, I work with people who ask for and trust my recommendations, and who are willing to spend more money for better quality.

Our last major projector purchase was 15 Epson 1985WU. I would have preferred the 1980, but others thought it was worth getting the extras like wireless display. (a feature we don't use, surprise surprise.)

I defiantly like the lens shift feature of the Panasonic, I have ton of PT-F300Us and FW300Us, they're great.
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Joined: Oct 11, 2016
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Wow - That is a very detailed reply, and well thought out!!

Just wanted to reinforce the fact that 1920x1080/1200 (FullHD) is absolutely not necessary for *MOST* classroom environments. I've been been doing AV for higher education for a long time now, and the max resolution I use in most cases is 1280x800 (WXGA).

As AV_Integrated mentions, Full HD just makes text far too small to read from distances further than 5-10ft.

There are so many calculations for screen/image size vs. distance to viewers, but the basic 150 Rule usually turns out as a nice estimate. (150 times text height = max viewing distance)

Regarding aspect ratio, I've always been a fan of 16x10 for screens, projector native resolutions, and local monitors. If you can match up all these devices at 16:10, there is no chance of issues with images not fitting within your screen. Of course, this will depend on whether or not you're using scaling devices as well. It's a tricky task to get a PC to output 16:9 to a local monitor, and 16:10 to a mirrored (Duplicate) external display. My preference is 16x10 all the way, with scalers in place to handle anything strange from a laptop or other input sources.

Bottom line, for a budget minded, well performing projector, I've been using the Epson PowerLite line for years now and have found them to be very good. They offer educational pricing (Look at the Brighter Futures price list - https://www.epson.com/_alfresco/LandingPages/landing/education/v2/pdf/pricing_bf-projectors.pdf )

I am currently installing the PL935W in any new instance or replacement. They are bright enough for most light classrooms, lamp replacement is easy and cheap, the quick corner feature is easy enough for a work study employee to use with good results, serial control is simple and flawless, etc.

Cheers, and good luck!
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It's worth saying, that while the above poster really does have good advice, I'm actually a fan of 16:9 far more than 16:10 for the screen and all subsequent displays.

ALL flat panels are 16:9, most are 1920x1080. Tons of local monitors are 1920x1080 and 16:9 native. More and more, the default aspect ratio for laptops is 16:9, not 16:10.

The advantage with a 16:10 projector is that it can project onto a 16:9 screen just fine. But, a 16:9 projector can't fill a 16:10 screen. So, that's why the recommendation for a 16:10 projector. But, I would almost exclusively pair it to a 16:9 screen.

By example, if you go to www.newegg.com and look at laptops, then scroll down to the resolution section, while there are a great number of 1280x800 (16:10) laptops (693) there are over 2,000 laptops that are 16:9 resolution in the 1366x768 resolution or the 1920x1080 resolution. 16:9 dominates the market!

Similarly with monitors, there are 1,000+ 1920x1080 monitors, but far fewer which are 16:10 aspect ratio.

It's taken a decade, but finally most PC manufacturers are using 16:9 as their standard on most laptops. Plus there's not one large format flat panel that isn't 16:9 aspect ratio produced right now.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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