Prices of 4K projectors have been falling rapidly. When we first looked at the the Optoma UHD60 and the Vivitek HK2288 four months ago, they were both selling for $1999, and at that price they were the least expensive 4K projectors on the market. At this writing the UHD60 has dropped to $1,799, the HK2288 is at $1499. And the ViewSonic PX727-4K (using the new 0.47" DLP chipset) is at $1299, and currently the least expensive of the 4K projectors.
The Optoma UHD60 and the Vivitek HK2288 both use the 0.66" DLP chipset. So they go head to head as the least expensive of the 4K projectors with this particular light engine. Though there is no visible difference in image detail or resolution between the 0.66" chip and the 0.47" chip, the larger chip enables engineers to design for higher light output. It also gives the designer some flexibility to achieve higher contrast as they work with trade-offs between lumen output and contrast.
The UHD60 and HK2288 each have distinct advantages over the other and they each have a few flaws. We will sort these issues out and let you decide which of these two 4K projectors sounds the most appropriate for you.
Brightness. The Optoma UHD60 is rated at 3000 lumens while the Vivitek HK2288 is rated at 2000 lumens. In practical use in normal video modes the UHD60 does appear brighter in side by side comparison, particularly with 4K HDR source material.
Both projectors have an exceptionally bright factory calibration that is decidedly green in tint and for the most part undesirable for video presentation unless you don't mind a greenish picture. On the UHD60, this green/bright mode is called Bright, and on the HK2288, you get it via the factory default settings in the User mode. Though these modes put out sufficient light to get close to their official lumen ratings, you get a lot better picture quality on both projectors by cutting down the lumen output in exchange for better color balance.
Both projectors have a selection of precalibrated color modes with varying lumen output. With lamps on their respective full power settings and the zoom lenses at their widest angle positions, our test samples yielded the following lumen measurements:
Optoma UHD60 ANSI Lumens
Vivitek HK2288 ANSI Lumens
Lamp Modes. The Vivitek HK2288 has a "Default" lamp power mode which corresponds to the Eco mode on most other projectors in that it is the least bright option. You have the option to select "Boost" in the menu to increase lumen output by 33%.
The Optoma UHD60 has a single Eco mode which reduces light output by 37%. Eco mode becomes an option when Dynamic Black is turned off. On our test unit there was a persistent flicker in Eco mode, indicating the light source or power supply did not like being run at that level. The picture is stable in both Bright mode and Dynamic Black, which are the two options you'd be likely to use anyway. Since you can turn down lumen output by reducing the Brilliant Color control on the UHD60, there is no need for eco mode.
Zoom lens light loss. The UHD60 has a 1.6x zoom lens that loses 26% of the projector's maximum light potential when set to the telephoto end. Very similarly, the HK2288 has a 1.5x zoom lens that loses 20% of its light at the telephoto end. So if you want to maximize light output, try to install these projectors close enough to the screen that you are using the wider angle end of the zoom range.
Picture Quality in SDR. Out of the box, with the UHD60 in Cinema mode and the HK2288 in Movie mode, the UHD60 shows a picture that is brighter, higher in contrast, and more accurate in color balance than the HK2288. However, a few tweaks will help to improve it. The UHD60's Brilliant Color setting defaults to 10, and unless you need the brightness it is better to reduce that setting to 7 or less to achieve a more balanced image. Ultra resolution defaults to 1 and should be turned off to minimize noise. Sharpness can be bumped up a couple notches without introducing noticeable artifacts. But these are personal preference adjustments and the picture is quite engaging even without these alterations.
In side by side viewing the UHD60 does in fact show a noticeable advantage in contrast when viewing SDR material. The picture looks slightly sharper and it has greater image depth (more three dimensionality) due to the higher contrast advantage. This becomes more obvious as you reduce Brilliant Color, which increases color saturation and contrast.
The HK2288's SDR picture on our particular test unit is biased toward a cool blue, and it is a bit more problematic. Color adjustments are difficult because the projector is set up to close the menu after each access of Hue, Saturation, or Gain on any R, G, B, C, M, and Y control. All navigation buttons on the remote close the menu once any change is made. This forces you to re-open the menu from scratch and navigate back to the Color section for each succeeding adjustment. Once you get to the Color menu there is no visiblity into how each of the colors are set. You need to open Red in order to see the current H, S, and G settings. At that point, even if no change is required, you need to close the menu and start from the top to get back to G, B. etc.
The HK2288's Movie mode is improved with some significant color adjustments. Making them is a more tedious process than it should be. However, it is possible to get the HK2288 calibrated and spun up to where the color is well balanced. Once it is done you should not need to adjust it further, so this flaw impacts set up more than ongoing operational use. Note however that color balance adjustments are more complicated than simple adjustments to brightness, contrast, saturation and so on. Most consumers will not be able to make proper adjustments to color without meters and some knowledge of calibration. The HK2288 will definitely benefit from professional calibration.
HDR performance. As with SDR, the UHD60's color balance is close to accurate while the HK2288 is skewed toward a cool blue. The UHD60's picture is vibrant and engaging right out of the box with no significant need for calibration other than to accommodate variances in HDR source material (common to all projectors).
From a lumen output perspective they are comparable. However, the HK2288's HDR contrast is more competitive with the UHD60, and at times exceeds it depending on the disc. On several, but not all discs, color saturation tends to appear overdriven on the UHD60 and weak on the HK2288. But we've also got an HDR disc that, prior to adjustments, plays both higher in contrast and saturation on the HK2288 than on the UHD60.
The bottom line is that when it comes to HDR, both projectors typically benefit from contrast, brightness, and saturation adjustments to accommodate each individual disc. The good news is that you can get very solid high contrast, well balanced HDR pictures from both of these projectors as long as you're up for some fiddling with the picture adjustments. This is not the fault of either projector, but the non-standardized output levels of the sources. And once you've got the pictures dialed in, they deliver a riveting, deeply engaging video experience, so it is worth the effort to tweak them up to optimum HDR performance for each source and disc.
Color Balance. Neither of these projectors are perfectly calibrated coming out of the box, but of the two the UHD60 is closer to ideal. The default calibration on the UHD60's Cinema mode is biased slightly toward yellow/green. Meanwhile the Movie mode on the HK2288 is biased more noticeably toward blue. Both are certainly watchable without adjustment, as the brain is almost infinitely accommodating of color errors. However when viewed side by side the UHD60's picture is subjectively the more pleasing since flesh tones in particular appear warmer and more natural.
The menu indicators regarding color temperature on both projectors need to be taken with a grain of salt. On the UHD60, D65 (while in the ballpark) is not a precise D65. On the HK2288, the "color temperature" options of Warm, Normal, and Cool are in reality varying degrees of cool; even the Warm setting (the default in all color modes) is biased toward blue and does not look like anything that we would describe as warm. However, Normal and Cool are definitely cooler than Warm.
Image Sharpness. We see somewhat different optical performance from these lenses. On the UHD60, the lens is very sharp in the middle two-thirds of the image, and tends to soften somewhat toward the sides and corners. However, the subjective viewing experience is one of a very sharp image since the eye rarely focuses on the sides or the corners of a big screen image; even when it does the softness is subtle enough that it does not look blurred in typical video material. The focus issue is mostly detectable when viewing a test pattern, a still graphic, or a financial spreadsheet. Conversely, on the HK2288, the image is more uniformly in focus across the entire screen.
Brightness Uniformity. The HK2288 performs better on this metric. With the lens at wide angle, uniformity is very good 79%, and at the telephoto end it increases to a solid 87%. Meanwhile, the UHD60 comes in at 64% at the wide angle end, and 74% at the telephoto end. Variations in brightness uniformity are typically seen only on solid white, gray, or single color test patterns. When viewing a solid white 100 IRE test image, there is no noticeable fading on the HK2288; it looks quite uniform across the screen. On the other hand, the UHD60 image fades along the sides. One tends not to notice this in film/video projection because (a) the eye tends to focus on the center of the image, and (b) you typically are not aware of what the brightness of the picture should be at the edges, so you don't interpret fading at the edges as unusual.
Input Lag: The UHD60 has an input lag of 63 ms with Dynamic Black on and 56 ms with Dynamic Black off. The HK2288 measured 62 ms.
Fan noise. The UHD60 has an audible noise rating of 28 dB compared to 35 dB on the HK2288. These specs reflect a real difference in fan noise, which is quiet on the UHD60 and more noticeable on the HK2288 when Boost is active for higher light output. However the HK2288's fan noise is very low in frequency compared to many other projectors. This makes the noise much less obtrusive than most other projectors with dB ratings in the 30s. When Boost is turned off, fan noise drops to a low and unnoticeable level, comparable to the UHD60.
Rainbow artifacts. The HK2288 has the edge here, with rainbows being virtually non-existence due in part to the RGBRGB color wheel. The UHD60 has an RGBCY wheel, and one may see rainbows on occasion with this configuration. Personally, I see them when testing with a moving test pattern designed to reveal them, but when viewing typical film/video, they are scarce and don't rise to the level of a distraction. Some people never see rainbow artifacts, some see them on occasion and are not bothered by them, some find them distracting.
On board Audio. The UHD60 has two 4W speakers mounted in the rear of the unit. The HK2288 has a single 10W speaker mounted on the side. The UHD60's audio is much louder and has better bass range, generally about the best audio we've heard from a projector. The HK2288's audio is functional if you need to hear a sound track, but less robust and comparatively thin. For serious home theater, neither would be a good option for permanent use. If you don't want to go for the full surround system, then consider an external sound bar.
Lamp Life. At the moment, Optoma is representing that the UHD60 will get 4000 hours in full power mode, 10,000 hours in eco, and 15,000 hours in Dynamic Black mode. That is notably longer life than Vivitek is quoting -- 3000 hours in its brightest (Boost) mode, and 5000 hours in Default.
Replacement lamps. A new lamp for the UHD60 is currently priced at $199, and a new lamp for the HK2288 is $319.
Warranty. The Optoma UHD60 comes standard with a 2 year warranty. The Vivitek HK2288 comes standard with a 3-year warranty.
When you first pull these projectors out of the box you get an immediate impression of build quality. The Vivitek HK2288 weighs 20 lbs. and is solid as a rock. Casework is sturdy and substantial. You feel this is a formidable projector that has been manufactured with attention to detail and quality. On the other hand, the Optoma UHD60 is not quite in the same league. It is 16 lbs, which is still quite large compared to most other 4K projectors under $2000, but the casework is thin, and you get the feeling Optoma cut some corners here. Opening the flimsy top panel to get access to the lens shift makes you worry you might snap it off if you don't handle it gingerly.
Once you fire them up, you begin to get a better impression of the UHD60. Fan noise on the UHD60 is very low, much quieter than you'd expect for a relatively inexpensive home theater projector. The picture in preset Movie/Cinema modes has remarkably good color balance that really needs no attention to enjoy out of the box. HDR in particular looks outstanding.
The Vivitek HK2288's picture out of the box is not as impressive as the UHD60 primarily because its factory default calibrations are skewed toward a cool blue. On the other hand the picture is sharper on the sides and corners and brightness uniformity is better overall. This projector is certainly capable of an equivalent, high contrast, well color balanced picture but most users will require the services of a professional to get it calibrated. This adds some expense to the proposition. The menu navigation itself is poorly done and is both frustrating and confusing.
Both of these projectors are larger and heavier than the other 4K projectors recently released in the sub-$2000 price range. They both offer some limited lens shift while the others do not, which can be quite helpful, especially in ceiling mounting. They both have moderately long zoom lenses of similar throw ratios, so your options for installation will be similar.
Neither of these projectors has any 3D capability. If you want 3D and 4K capability in the same projector and want to stay under $2,000, your current options are either the BenQ HT2550 at $1499 or the Epson Home Cinema 4000 at $1799. Of the two, the Epson 4000 delivers substantially better 3D performance.
In general, we have seen a rush on the part of manufacturers to move into the 4K sub-$2000 price niche as rapidly as possible to establish market share. As a result, the 4K products tend to manifest a few more flaws and missing features than one would otherwise expect. The good news is that 4K resolution has rapidly become available to the wider consumer base at prices far below where we would have anticipated they would be a year ago. And even with the flaws, you can get some outstanding large screen performance.
The fact is, we get fully engaged in the riveting, sharp, high contrast picture of the Optoma UHD60 despite its soft edges and lower than average uniformity simply because those flaws are not normally visible in the viewing experience. The Vivitek HK2288 is also a beautiful projector once you've done the color recalibration required to remove the bluish cast and warm up the flesh tones. And for $1499 it is an outstanding value. Many buyers are obviously diving into the 4K experience at these prices despite the various limitations inherent with each product. Many others are waiting for the next generation.