You can't directly connect a USB drive for photo or video viewing. The USB port is only for power or using the projector's remote as a makeshift mouse.
Viewsonic's remote is small and confusing, and worst of all lacks backlighting. I did appreciate the inclusion of a detachable cover to hide the cables, although it expands the projector's footprint. Sans cover the PJD7828HDL measures 12.44 by 8.98 by 4.08 inches (WHD).
Picture quality details
Like the Optoma and other full-HD projectors I tested, the Viewsonic easily outperformed the two less expensive projectors I tested recently, the iRulu BL20 and the Epson Home Cinema 640. The biggest obvious improvement was in resolution: blown up to 120 inches diagonal, the picture really benefitted from having all of its 1,080 pixels on the screen. Details were sharp, edges were smooth and there was no visible pixel structure (screen door effect) so the entire picture looked much closer to what I'm used to, detail-wise, from a 1,080p TV. Just much, much bigger.
Compared with the Optoma the Viewsonic held its own, although I liked its image a bit less overall. The two were similar in terms of overall color accuracy (and both had their flaws), but the Viewsonic's gamut coverage was much smaller according to my measurements. For its part the Viewsonic put out a somewhat brighter image while maintaining similar black levels, for a win in overall contrast on paper.
Comparing the two directly with the colorful Chapters 3 and 4 of the "Samsara" Blu-ray it was tough to see the difference, but with the subtler "Tree of Life" (Chapter 2) the Viewsonic showed a slight disadvantage in skin tones and the greens of the plants. The two were neck-and-neck overall, however, and both scored the same in this category.
The higher-end BenQ HT2050 ($800), another 1080p DLP, outclassed both by delivering a deeper shade of black, and comparing it with the Viewsonic I could see a slight difference on my big screen. The BenQ delivered just a bit more realism in dark scenes like the void of space in "Gravity." That said, the difference was subtle enough it would be tough for truly budget-minded buyers to justify the price difference based solely on that advantage.
It's worth noting that all of these units suffered from an artifact I found distracting at times that's common to DLP: the rainbow effect. It caused brief rainbow "trails" to appear when I looked across or away from the screen in high-contrast areas (like white text against a black background). It didn't bother me much during the course of a movie, but if it bugs you, a projector like the Epson Home Cinema 2045, which uses LCD instead of DLP, might be a better bet.
To arrive at all of results below I measured the Viewsonic's best default picture setting, Movie (I did not perform any calibration). The exceptions are peak white luminance and derived lumens, which were measured in Brightest mode (thanks to Chris Heinonen for the lumens calculator). All observations and measurements were taken on my reference 120-inch Stewart StudioTek 130 screen, and comparisons with other projectors performed by alternately blocking their light.
|Black luminance (0%)||0.035||Average|
|Peak white luminance (100%)||93||Good|
|Avg. gamma (10-100%)||2.35||Good|
|Avg. grayscale error (10-100%)||5.586||Average|
|Dark gray error (20%)||4.727||Average|
|Bright gray error (70%)||6.064||Average|
|Avg. color error||8.193||Poor|
|Percent gamut (Rec 709)||85||Poor|
|1080p/24 Cadence (IAL)||Pass||Good|
|Motion resolution (max)||300||Poor|
|Motion resolution (dejudder off)||N/A||N/A|
|Input lag (Game mode)||33||Good|