Controlling Presentations from iOS/Android Devices
With some of today's projectors, you can use a mobile device - iOS or Android, to remotely control a computer, thus being able to run a presentation, and with the use of additional software (app), do interactive features, such as annotating.
The Mitsubishi WD390U, reviewed spring 2013 is one that can use on of those mobile device to control the computer that's presenting through the projector. With my iPad, for example, I can annotate, load images and programs, run videos, close documents, edit them, and draw over them, as long as the app is well designed and the computer's matching program is too, as that Mitsubishi demonstrated.
We even created a video that included a demonstration of controlling a computer at the other end of a server network. If you are curious check that out. The WD390U video contains a demo of these features, that starts X minutes and seconds into the video.
When discussing wireless networking, we are often talking about one or multiple computers talking directly to a projector that has wireless networking built into it.
No, we're not talking sexual orientation of a projector, I'm not even sure how to tell the sex of a projector. In this case we're talking about the physical orientation of the projector. Can it be used rotated, say pointing straight down, or on a side angle, so that perhaps the image is at a 45 degree angle. There was a time when basically every projector had to be oriented horizontally. You could set it on a table, or mount it. Whether right side up, on a table, or inverted on a ceiling or wall mount, those were your choices.
Today, however, mostly with medium to large "install projectors" we are starting to more projectors that can be placed vertically - essentially turned on their side. There are some that can be pointed down or up 45 or 60, or some other number of degrees. Mitsubishi, as one example, has a whole series that can work from virtually any angle.
Again, like with edge blending, this extra positioning flexibility - orientation - is most likely to be needed in unusual situations. Again museums, digital signage, and special projects would be where this ability might be needed, not in a normal classroom or auditorium, although such a feature might help out in an auditorium where the projector cannot be mounted where it would otherwise be most traditional.
Having an assortment of interchangeable lenses is feature rarely found on projectors weighing less than 10 pounds and rarely inexpensive. Certainly, though you can find projectors with lens options starting at under $3000. Traditional small projectors typically setup or mount easily in typical room. But in some cases projectors have to be way way in the back of a large room, or be very or ultra short throw to be used in a rear screen setup.
Most of the lower cost projectors that do have multiple lenses tend to have just three, maybe four. As you get into higher end models there might be six or eight or more lenses. Generally the basic lens set would consist of a "standard" zoom lens for typical installations, then there would be a wide angle zoom for placing closer than the standard lens. from perhaps very short throw to wherever the standard lens starts in terms of distance.
Finally there will be a long throw zoom, perhaps with a lot of range, maybe a 2:1 zoom. With just those three lenses a projector needing to do a 10 foot diagonal image might be able to be placed as close as 4 or 5 feet from the screen, to as far back as 50 or 60 feet. If there are about six lens choices, then add a fixed ultra wide angle lens for rear projection, that might place the projector only 2-3 feet from that big a screen. And you would get a Very long telephoto and maybe a really super duper long telephoto lens. Thus for that same sized screen, almost anything from about 2-3 feet to perhaps 200 feet will work. When you think of needing very long throw and longer telephotos, that's usually means mounting projectors at the rear of an auditorium or outdoor venues - maybe hotel ballrooms. (Houses of worship too.)
Lens costs can be astronomical, at least compared to the perceptions of people who use smaller projectors. You can certainly find lenses that sell for $5000 and probably $20,000 for the biggest large venue projectors (Dodger Stadium comes to mind). But with most more moderate projectors figure standard lenses might be had for $500 to $2000, and the other lenses more like $1200 to $6000. Most typically, lenses priced around $5000 or so, exist for projectors in the $10,000+ range. For less expensive projectors figure $1500-2500 for most lenses. But think of the advantages. Mount a projector high, 30 feet back from the screen in an auditorium, and any servicing becomes a nightmare. Spend another couple of grand, or so, and you mount the projector somewhere far back, but far more easily accessible. It won't take a man day to remove the projector if it needs servicing, or a half man day to change a lamp or replace a filter, instead it might take 5 minutes (20-30 minutes for the lamp replacement if the projector needs to cool down).
As to short throw and fixed short throw lenses, they provide the benefits associated with having the projector close in. Less blinding of the "presenter" is one benefit for use in front projection, but rear projection offers its own massive benefit: With rear projection, limiting the ambient light behind the screen (drape it in black) the projected image gets no more washed out by ambient light in the viewing room, than a LCD or Plasma would. It's the light behind the screen that becomes important, and since that's a small area, it's easy to darken, while the rest of the room is well lit. Rear screen projection is widely used by companies and organizations in events held in hotel ballrooms.
There are also speciality lenses for different applications, anamorphic lenses to stretch an image comes to mind. (Think about all those 4 foot tall hobbits, in Lord of the Rings) Bottom line: Most applications other than larger venue, (including larger classrooms at universities) do not need other than a standard lens. But it's nice to know today, that interchangeable lenses are even available on projectors under $3000, should you have the need.
Classroom Projector Lamp Life and Cost of Replacements
Long lamp life is a feature, the benefit is lower cost of operation. One thing that never changes, and that's that most school districts don't have near enough money for technology as they would like. Hopefully for all the IT and AV managers at the schools and districts, there won't be any significant hit to federal funds used for school technology purposes, at least not beyond the Sequester. I know that when I owned a dealership, a large chunk of the money being used by districts buying high volumes of projectors from us, was coming from Federal programs. Well, so far, no one has accused the Obama administration of slashing spending, so for everyone's sake (yep, even the students), there's money for some more projectors this summer.
With things as tight as ever, it's smarter than ever to look at the longer term costs associated with projector purchases. Consider, it might be nice to save $100 a projector up front, but it wouldn't be smart, to go with that projector, if it's going to end up costing you $600 more to operate it for 5 years. When projectors are getting lots of use (and many people realize that while a projector can get tons of use in many classrooms, the reality is many other teachers don't use them much at all, and some, not at all). That just makes the math trickier, but the fundamentals are unchanged. Let's consider a projector as having a 10 year life (what school doesn't try to get at least 10 years out of a projector)? Let's say we have two projectors. One costs $800, the other costs $1000. We'll also assume they are similar in all ways but lamp life and cost.
In a hard core powerpoint world you'd have a school tech sitting at a table with 3 projectors each with a pile of bulbs based on how many it would take to last 10 years at x hours per week. The less the lamp life and the more the replacement bulb costs, the smaller the pile of remaining cash... I would like you to cook up something good, but not now. But PLEASE make a note, and get it done before we leave, K? Projector A: $800 cost. Lamp life is 3000 hours in low power mode. We'll assume today's projectors are bright enough that low power can be selected to extend lamp life, save money. Replacement lamp cost is $300 Projector B: $1000 cost. Lamp life is 5000 hours in low power mode. Replacement lamp cost is $200 Let's see how they stack up in cost, over a decade. We'll use three examples, 8 hours a week, 12 hours a week, and 30 hours a week.
Scenario 1 calls for 8 hours a week, Projector A needs a new lamp at 3000 hours, since 8 hours a week is about 300 hours a year (remember, we're talking a teaching year). That means at the end of 10 years, the first lamp needs replacing. Well, if the life of the projector is only 10 years, then there's no impact. The same would be true of Projector B.
Scenario 2, however, has Projector A requiring a replacement lamp around year 7, at a cost of $300. That brings the projector's total cost to $800 + $300 = $1100. Projector B with its longer life lamp, still has no need for a lamp at the 10 year point, so the total cost is $1000.(OK, we're not factoring in the Present Value of money, adjusting for inflation, etc., but you get the idea).
Scenario 3, is an eye opener: At 30 hours a week, that's about 1100 hours a year. For projector A, to get all the way through year 10, you will need to purchase a total of 4 $300 lamps. That makes the total $800 + $1200 = $2000 For Projector B, though only one $200 lamp is needed. The math: $1000+ $200 = $1200. That sure makes you want to consider lamp life and cost, as a key part of selecting projectors. Now let's take a spin at the cost issues for projectors with digital light sources: Laser, LED, or Laser/LED combinations. Most of these are rated 10,000 to 20,000 (mostly 15,000+) hours for their light sources. Like lamps they too lose brightness over time, but since the time is so long, it should take years before one notices a non-lamp projector has dropped brightness noticeably. Figuring out the long term advantages of digital light sources, from strictly a cost standpoint, is challenging. That's because it's hard to quantify how much one is paying extra for that light source.
All considered, on typical classroom projectors (not some extremely bright high end ones), figure you are paying $600 to $1200 more for such a projector. In our most extreme example above - Scenario 3, we're looking at about 11,000 hours of use over a decade. Almost all digital light source projectors can therefore make it through a decade without any extra expense. Where does that leave you in the decision process? The digital light source - LED projectors, Laser Projectors will not need any extra expense to make it through a decade of 30 hours a week (for a typical school year). That should place them still being significantly more expensive than those projectors with low cost traditional UHP lamps that are very long life, and, less expensive in the long run compared to those with more expensive lamps, and not exceptionally long lamp life.
Consider a typical Epson projector suitable for education. Their Education pricing for lamps is typically $79 or $99 each. They are all rated at least 4000 hours at full power, most of their lamps 5000 or 6000 if running in eco mode. For most, 10 years of 30 hours would require only $160 in extra lamps. Just remember there are other costs. It takes labor to change out a lamp, and if you are responsible for a school district with 500 projectors, even if most only need a new lamp every 5 years, that's still 100 projectors a year getting new lamps.
Considering they are scattered around, that's probably about 1/4 person year of labor. If that's $15,000 in labor, then you better figure the real cost of replacing a lamp labor wise is probably over $100. So a projector that needs two lamp replacements over a decade, has a definite additional cost component. Here's a bizarre comparison - or rather a look at another parts vs. labor comparison. At a school or college, there are many custodial engineers (we used to call them janitors - not sure what the official description is today). Which costs more, paying all those engineers to change the toilet paper in the bathrooms, or the cost of the toilet paper. I'll let you stew on that question. The point is, the shorter the lamp life, assuming the projector will be used for many years, the greater the labor cost as well.
Other Costs of Operation
You thought you were going to get out of math class that easily? Sorry, still a couple more points for me to make. What else affects long term cost of operation? 1) Repairs, and warranty duration as it relates to any needed repairs 2) Installation related costs (cabling, accessories, mounts, extra speakers if needed, etc.) 3) Routine maintenance costs (changing filters, lamps, etc.) While it's really difficult to predict which products will prove to be the most reliable, some brands do have better reputations than others, for reliability. Support also varies a good deal. And should a projector break under warranty, is there a replacement, a loaner, or do you ship yours into a repair facility? Who pays the freight? We can only help you with some of these questions, and they will be addressed on the Warranty page. Still, if all else is equal, you want a projector with a longer warranty. A replacement program is great, for it normally means that the user is down only 24-48 hours. A loaner program is similar. Some districts prefer loaner programs to replacement ones because they use asset tags to track all their, well, "assets" including projectors. That means if a projector is replaced (not repaired), it means a bunch of paperwork to change all the asset tracking, and to afix a new asset tag on the replacement projector. On the other hand, other districts could care less, and are just happy to get the teacher back up and running in 48 hours or less. Time, as they say, is money! While even over a decade, most projectors would not see more than one or two lamp changes, there are more frequent sources of maintanence.
Air Filters And Changing them
There are basically four levels of filter maintenance: No filter to change, A filter to change infrequently, say every 1000 hours, A filter that needs changing frequently (say every 200 hours of operation), and finally, since this feature now exists, filters that get replaced only when the lamp gets changed. In most of the last type, it's a projector with a "rolling" filter - one that simply rolls forward a clean segment of filter, every so often.
Obviously the first and fourth types require no extra maintenance, and even the infrequent filter change is a relatively modest amount of work. But a filter than needs to be changed every 200 hours would be an operational nightmare if for 200 of these projectors, scattered over 20 schools. On average, assuming the short filter life, most projectors will need from one to three filter cleanings or changings a year, even allowing that you don't quite maintain the recommended level of maintanence. Two hundred projectors - let's say 2 changes a year each. You've got to figure that's about a man year worth of filter changes. That's two a day (based on a not quite realistic 200 days per school year).
Considering the logistics of multiple schools, etc., inconvenient access, one man year of labor isn't wholly unreasonable, maybe rather low. If you can buy a projector requiring none of that, it's a huge savings, but truth is, almost all of the projectors today have minimal maintanence. The old 100 hour standard is long dead and buried. There may still be a few projectors around still requiring that type of frequency, but they're not likely to be targeted at schools. 1000 hours plus is more normal if a projector has a filter at all. DLP projectors are almost alway filterless claiming a sealed optical system. LCD projectors are not sealed due to the different technology type.
Overall, DLP projectors aren't perfectly sealed, but there's never been a problem to my knowledge about dust in the lightpath. On the other hand, many of us have seen the inside of an 3 or 5 year old desktop computer, or an old piece of stereo gear, or an old TV, at some time in our lives.We've seen the incredible pile up of dust and dirt inside those PCs. It can't be good. That causes devices to run hotter, which in turn shortens component life. So being completely filter free isn't as perfect as it sounds. Generally I would say that as long as any filter cleanings or replacements are really infrequent, its not an issue to have any real concern about. In some cases, I should note, filters will be replaced with the lamp is replaced. We even recently reviewed a projector who's filter will outlast 3 lamps. (12,000 hours!)