My Friend Iris
Some of you may have noticed that we posted updates last week to our reviews of a couple of budget 4K projectors, the BenQ HT2550 and BenQ TK800. You can read them to find out what changed, but the bottom line is that BenQ made some significant improvements to the HT2550 after our evaluation of an early review sample last spring, and it changed our perspective on the product as well as how it compares with its sibling TK800.
I mention this because looking anew at those reviews from earlier in the year, for 4K projectors that cost all of $1,499, got me thinking about what you can get for your projector dollar these days. There's no real case you can make in which these two models aren't a tremendous value. BenQ has a reputation for delivering a lot of projector for the money, and the idea that you can get any true 4K-resolution projector today for less than $1,500 is amazing in and of itself, considering that the entry point was $5,000 just a few months prior to the introduction of these machines. And, of course, BenQ has plenty of competition now in the sub-$2,000 arena, almost all using one or another of Texas Instrument's new-generation 4K DLP micromirror chips.
There's no denying that the arrival of these 4K DLP devices was a game changer for the 4K projector market. Even putting aside resolution, lower-cost 4K DLP projectors widen the access to 4K content with high dynamic range HDR and wide color gamut, each of which has the potential to provide even more discernible benefits than the extra pixels.
So, the news is all good, right? Well, kind of. If you're serious about home theater, you might want to ask yourself what we might have given up for the privilege of mass-market 4K projection. I'm not implying that the DLP solution, which involves pixel-shifting to acheive 4K resolution, is inferior to the native 4K imagers we've seen from Sony, JVC,or others. I'll refer you to the work of my colleague Evan Powell, who faced off the various forms of 4K and 4K-compliant 1080p pixel-shifting projectors in his article True 4K vs Faux K. His basic finding was that subtle differences do exist, but they tend to disappear at normal viewing distances with moving video content (still graphics may yield different results). For home theater, all the 4K imaging technologies, even the 1080p pixel-shifters from the likes of Epson and JVC that deliver something less than UHD's full pixel count, have the potential to deliver clean, detailed images with UHD programming.
More critically, Evan discusses in this article how different factors beyond resolution generally affect image quality, even the level of detail. Better contrast, for example, gives the perception of sharpening the edges of objects by putting them in greater relief to their surroundings, and also improves the dimensionality of the image by better reproducing shadow details. But there's more. I'll quote Evan here: "There are many important factors that contribute to a 4K projector's success. Certainly contrast is a critical one--both with HDR and SDR. But also the level of digital noise, the image enhancement video processing, the color balance and saturation, and the optical precision of the projector's lens, all contribute to making a 4K projector's picture great or less than great."
Before 4K DLP came along, the value quotient for budget 1080p projectors in the $1,000 to $2,000 range was steadily rising. Year after year, the focus was always on contrast and getting deeper black levels. It was assumed you were using the projector in a dark room, and manufacturers were fixated on making whatever incremental gains they could in lens quality and contrast. Below a certain price point, you gave up some light output (but never so much that you couldn't fire up a 100" screen in controlled light), and you lost some niceties like motorized lens controls. But the most critical thing you probably sacrificed as you stepped down in price was a dynamic/automatic iris that would shut down the lamp output on darker scenes and help improve the black level and contrast ratio.
Times have changed, and the demands being placed on projectors are evolving. Greater lumen output is often needed today to accommodate projection in high ambient light, and the need for brighter highlights with HDR content runs counter to the longstanding goal to further darken the black floor. Given these demands, if I have any issue at all with the lowest-cost 4K projectors out there now, it's that in most cases they eschew an auto iris for improving dark scenes. Dynamic contrast processing on the video signal, which we do thankfully find in most of these projectors, can certainly have a positive effect and makes these models recommendable. But assuming an auto iris is well engineered to avoid the most obvious forms of brightness pumping associated with the worst of their ilk, its effect on the most revealing dark scenes should always be additive to the baseline contrast you can get without one.
At the moment, the only 4K-compliant projector in this under $2,000 price bracket with an auto iris that I've been able to find in our database is the brand new Epson Home Cinema 4010 that's in my studio right now for evaluation. This is not a native 4K projector, but a pixel-shifting 1080p model that, on paper anyway, sacrifices some resolution compared with the 4K DLP competition. I'll have a review of the 4010 completed shortly. But what I can tell you for now is that on my usual black-level torture scenes, turning the auto iris off from its default High Speed position clearly washes out shadow details and dulls the brighter highlights. So the iris is--for me, anyway--a meaningful feature whose benefits have the potential to be seen on a day-to-day basis. Would my investment dollar be better spent buying a full 4K model that lacked the iris? I don't have a full 4K projector in house right now to check against the Epson's obviously crisp picture, but I'm guessing that I wouldn't see terribly much difference.
I guess the point of all this is that there are lot of places a manufacturer can invest product budget to add value in a $1,500 to $2,000 4K projector. Some might choose to put it into a 4K imaging chip--or be forced to pay the price for that and sacrifice other features just to participate in the 4K game at the lower price points. Others might choose to go the 1080p pixel-shifting route. Some may skip a fancy dynamic iris, and put their limited budget into a higher quality lens with a wider zoom ratio, or a more advanced, 18.2 Gbps HDMI port that handles 4K content at a 60 Hz frame rate—something that makes a machine more attractive to gamers and is noticeably absent in the 4010.
I do expect that the projectors in this price class will continue to evolve year to year, and that consumers will continue to be the winners, with increasingly better performance and features being offered for the same price (or less) in each successive generation. Projector makers will continue to make their trade-offs, and we buyers will continue to weigh them. The best advice we can give is to do as Evan suggests: take a step back from the pixel race, and look at all the criteria that contribute to making a 4K projector's picture great...or less than great.