Our main issue with the Insignia NS-PDP42's performance is its tendency to temporarily retain after-images in dark scenes--an issue colloquially known as "burn-in." In other areas it's a middling performer, and if not for this issue we'd improve its score into an area competitive with models from Vizio, Westinghouse and other budget brands.
Although the overwhelming majority of plasma HDTVs we test have no problem with burn-in, charitably called "temporary image retention," the Insignia's problem with retaining images is simply unacceptable. If any part of the screen displayed still images for a few seconds, such as the grid of our DirecTV programming guide, the news ticker on CNN, the menu of a DVD, or even a paused screen while we were watching TV, an after-image would remain. The after-image was most noticeable when viewing darker scenes, but we noticed it even in lighter scenes with a bit of darkness, and if the screen faded to black it was quite obvious--at times the darker parts of scenes displayed a palimpsest of old tickers, menu items, program grids, and sports scores. We ran the Insignia for as long as we could during our review period, overnight in a couple of cases for a total of about 70 hours by the time this was published, and this issue persisted. (Update 4/30/2008: We've put more than 300 hours on the Insignia since this review was published and the image retention issue is still as severe ever.)
We haven't seen nearly this level of temporary retention on other plasmas we've tested, even during their initial 100 hours of operation, so the NS-PDP42 is definitely unusual in this regard. At least the Insignia's retention was temporary in all cases (it faded after awhile of playing moving images or the white screen from the ISM menu), but overall it's still very problematic in our opinion, especially given the current state of the plasma art.
Moving on, for comparison testing we first reduced the light output of the NS-PSP42 to a respectable 40 footlamberts, our target for viewing in a dark room, and calibrated the other settings as well as we could. We also tried tweaking the user-menu color temperature controls to get the grayscale closer to the 6,500K standard, but we couldn't improve on the measurements we got in the default "Warm," preset, so we left it there. For our complete dark-room picture settings, click here or scroll down to the Tips section.
After setup, we sat down to compare the Insignia with a few other HDTVs we had on-hand--all more expensive than this model, but still worthy of comparison just to see how the entry-level NS-PDP42 stacked up. Comparison models included the Olevia 252T FHD, a 52-inch LCD; the Philips 47PFL9732D, a 47-inch LCD; the Panasonic TH-50PH9UK, a 50-inch plasma; and our reference displays for color and black level, the Sony KDS-55A3000 and the Pioneer PDP-5080HD. We watched the RoboCop Blu-ray on the Sony PlayStation 3.
We didn't expect the inexpensive Insignia to produce a very deep shade of black--and compared with the other sets it didn't--but then again, its blacks were better than those of a lot of low-buck plasmas we've tested, such as the Vizio VP50 and the Hitachi P50H401. On the night when RoboCop first takes his Taurus LX on patrol, for example, the shadows of the buildings and the spaces inside his car appeared lighter than they did on the other sets, with the exception of the Olevia LCD, which was about equal to the Insignia. Details in shadows were also less-apparent on the Insignia, which tended to get too bright too quickly--a sign of improper gamma. Then again, for the price, black level performance was certainly acceptable.
We can say the same about the other crucial area of HDTV performance: color. Helped by the NS-PDP42's relatively accurate grayscale in the Warm preset, skin tones, such as the close-up on Peter Weller's chin and mouth beneath the mask, looked realistic and not tinged by the bluish cast that plagued the Olevia, for example. Our main compromise was having to desaturate the image a bit to make up for the red push in the set's color decoding, which (along with the slightly lighter blacks) deprived the image of some impact.
Primary color accuracy was a bigger weakness of the Insignia, especially in green areas, although it wasn't as bad as that of some plasmas we've reviewed. When Robocop pulls up to his old house on Primrose Lane, the trees and grass of the neighborhood looked a bit bluer than on the Sony, but the difference wasn't drastic.
We did, however, notice more noise on the Insignia than with other sets in the room. As the camera pans over the white model of future Detroit in the boardroom, for example, we saw more motes of snowy noise on the NS-PDP42, even when we engaged the "DB noise" function--which didn't seem to have much effect at all--and left the other sets' NR turned off. On the other hand the NS-PDP42 wasn't as prone to false contouring as many plasmas we've reviewed, especially for a budget set.
As a 1,024x768 HDTV, we expected the Insignia to resolve more detail than it did when fed 1080i sources. It truncated more 1080i resolution than other 1024x768 plasmas according to test patterns, although the 720p patterns looked a lot sharper. As a result, we recommend going 720p when possible, especially since the Insignia didn't properly deinterlace 1080i sources, whether from video- or film-based sources. The set cannot accept 1080p sources, which isn't a big surprise for something in this price range.
With standard-definition sources, the Insignia did well on most tests, but its ability to combat video noise was poor. The color bar pattern showed that the set could handle all of the detail of the HQV DVD, and details in the grass and the stone bridge looked relatively sharp and well resolved. The moving diagonal lines on the stripes of a waving American flag evinced some jaggies, but the set still did an above-average job of smoothing them out. When we finally tracked down the noise reduction feature, labeled "DB noise" in the DB menu, we really couldn't see much noise reduction at all in the low-quality shots of night skies and sunsets from the disc--they appeared as filled with video noise and "snow" as we've seen on any HDTV. When we engaged "Cinema 3:2" mode, the set evinced fine 2:3 pull-down, removing the moire from the grandstands behind the racing car.
With PC sources, the Insignia did fairly well. First, we connected a PC via an HDMI cable (DVI works the same way), and the set resolved every line of its 1,024x768 native resolution with no overscan and nice, crisp text. Next, we tried going in via VGA, and while the results weren't as good, the PC image was perfectly acceptable for light PC monitor duty. The set couldn't resolve every detail or horizontal resolution, exhibiting some softness and interference in the highest-frequency areas, but text was still perfectly legible.
|Before color temp (20/80)||6571/6462||Good|
|After color temp||N/A|
|Before grayscale variation||+/- 197||Good|
|After grayscale variation||N/A|
|Color of red (x/y)||0.657/0.327||Average|
|Color of green||0.257/0.672||Poor|
|Color of blue||0.148/0.057||Good|
|Black-level retention||All patterns stable||Good|
|Defeatable edge enhancement||No||Poor|
|480i 2:3 pull-down, 24 fps||Yes||Good|
|1080i video resolution||Fail||Poor|
|1080i film resolution||Fail||Poor|
|Insignia NS-PDP42||Picture settings|
|Picture on (watts)||216.76||203.87||137.64|
|Picture on (watts/sq. inch)||0.29||0.27||0.18|
|Cost per year||$66.67||$62.76||$42.64|
|Score (considering size)||Good|