HP Stream 7 Review: A $119 Windows Tabletby Brandon Chester on December 19, 2014 8:00 AM EST
The display is one of the most important aspects of a device, as it's the portal for interaction between the user and the software. Unfortunately, with inexpensive devices like the Stream 7, the display is often the first thing to be put on the chopping block. It's simply very difficult to put a high quality panel in a low cost device and make money selling it. That being said, HP has actually attempted to put a decent panel in the Stream 7 considering its price target.
Like I stated before, many other tablets at this size and price point either opt for a TN panel, or they reduce the resolution to 1024x600 or even go lower to 800x480, which is borderline unusable. HP has put a 1280x800 IPS panel in the Stream 7, which is fairly good considering that two years ago most Android tablets of any size shipped with that same resolution. The glass is highly reflective, and this is coupled with the fact that the display isn't laminated. There's also some light bleed at the bottom, but at $119 I can excuse this.
Of course, specs that you read on paper like size and resolution only tell part of the story. Color accuracy, brightness, and contrast all have an impact on overall display quality, and to measure these we use SpectraCal's CalMAN 5 software along with X-Rite's i1Pro 2 spectrophotometer and i1Display Pro colorimeter.
As you can see, the brightness of the Stream 7 is competitive with other tablets. Unfortunately, the black levels are just too high, which in turn leads to a very low contrast ratio. It should be noted that these measurements were achieved by disabling Intel's Display Power Saving Technology (DPST) feature, which causes dynamic brightness and contrast depending on the image displayed on the screen. While some other devices do this to some degree, DPST ended up reducing max brightness measurements by nearly 100nits, and the constantly changing brightness played havoc with measurements during analysis and calibration.
In the grayscale we see a shift toward blue, with the red steadily dropping off as brightness increases. This leads to the grayscale performance being some of the worst we have tested, but at $119 there's really no room for HP to do any calibration to the display panels at the factory.
As with the grayscale test, we see poor performance in the saturation sweep. The display does not cover all of sRGB, and we see that for each 20% increment in the saturation sweep, the red, blue, and magenta saturations are all 20% lower than they should be and just generally inaccurate. The poor grayscale and saturation performance leads to a high average error in the color checker test, which means that the Stream 7 is not going to be able to accurately reproduce colors.
Again, this is to be expected with a device of this price point. It does however provide a good example of how the idea that IPS technology correlates with color accuracy is a misconception. With the prices of IPS displays being driven into TN territory by affordable eIPS panels, having an IPS display really just guarantees better viewing angles than a TN panel, nothing more.
One last thing to note about the display which does not show up in any measurements is that it is a 6bit + AFRC eIPS panel. This is not uncommon even in desktop monitors that cost as much as $400, but it does mean that there is noticeable posterization compared to a display with actual 8-bit color depth for red, green, and blue. This is not helped by the fact that Internet Explorer is not smart about displaying images; it doesn't seem to apply the same dithering that Chrome and Firefox do to mask color banding.
Fortunately, the HP Stream 7 runs Windows. Unlike Android and iOS, Windows has color management capabilities. This allows us to calibrate the Stream 7 in an attempt to fix some of the issues with the display. We are working with a narrow gamut panel here so we aren't going to see much improvement to the saturation test, but we can certainly improve grayscale and color accuracy within the display's gamut.
After creating and applying an ICC profile created by CalMAN, we see a dramatic improvement in grayscale performance on the Stream 7. Gone is the shift toward blue, with a white point of 6595K that is very close to standard. Shades of grey are now accurate enough that you would be unable to see a difference from a reference monitor. These improvements unfortunately are accompanied by a significant drop in luminance, with a max display brightness of 308.5 nits after calibration.
We see slight improvement in the saturation sweep, but it's still nothing exceptional and unfortunately bound by the display's small color gamut. However, there's a significant improvement in the color checker test, although much of this can be attributed to the improvements in grayscale. There is an overall improvement in the accuracy of colors, but a few colors actually have a greater error after calibration than before. The biggest improvements are to mixtures of green and red, which has a significant impact on photos and videos by improving the accuracy of skin tones.
Overall, I'm surprised that the Stream 7 was able to be improved this much. It's certainly not perfect after calibration but it's much better. Unfortunately, I don't think many buyers of the Stream 7 are going to have the necessary equipment to calibrate the display properly, so it's more of an academic exercise.
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sonny73n - Saturday, December 20, 2014 - linkSony would never send their junks to this reputable site.
hpglow - Friday, December 19, 2014 - linkHow many times can you bitch about the lack of Sony reviews in these comments sections?
sonny73n - Saturday, December 20, 2014 - linkWhat about it? Sony Z3 phones are garbage. I just bought a Z3C from BH Photo last week. I thought 10+ positive reviews from popular tech sites couldn't be wrong. Turned out I've made the biggest mistake. You want one of the Z3 phones review? Here it is:
Pros: Good looking, great battery life, micro SD slot.
Cons: Display is the worst I've seen on a smart phone beside other Sony junks of course. Touch panel patterns are clearly visible whether the screen is on or off. Color shift when tilt. Sony stock firmware contains spyware Baidu and bloatwares. Unlock bootloader will delete the TA partition which contains DRM keys.
Other thoughts: I wish its display has the same quality as my old iPhone 4 which was from 5 years ago. I bought 3 Sony phone in the past 2 year. First the ZR, it got very hot even at browsing the internet - returned. Second the ZL, it got uncomfortably warm at normal use. Both phones displays made with TFT panels which are just terrible. Now the Z3C after very careful consideration because of those 2 ZR and ZL but this time it just pisses me off so much. Let me repeat - the Z3C display is worse than the iPhone 4's aftermarket ones on eBay which just costs about $14 each. Sony is nothing but a scam. They didn't post the display types for those 2 ZR and ZL on the spec sheets. Now I wonder the Z3C IPS display is some new kind of low cost IPS tech they just invented. I'd rather have a TN display with no visible touch patterns than this junk they claim ips.
Wolfpup - Tuesday, December 23, 2014 - linkAre you serious? They've got malware on their stock phones?!? Yowzers, I almost bought one for the waterproof-ness, but ended up going with a Nokia 635 'cause figured it's cheap so if it gets damaged....well, it's cheap. (And actually I like my 635 quite a lot too as a phone...I think 90% of people would probably do just fine with it and don't need a $650 phone lol)
victorson - Saturday, December 20, 2014 - linkIf you are thinking that this subsidizied pos tablet is any different than what the Chinese are doing, good for you, but you have little touch with reality. I've had the chance to use and review the latest top smartphones from Xiaomi and Meizu, and those are nothing short of amazing smartphones, and yes, they are getting regularly updated
Gich - Friday, December 19, 2014 - linkNo one? I do.
zero2dash - Friday, December 19, 2014 - linkObvious troll is obvious.
Why are you reading articles on "boring devices" and then bothering to leave a troll comment on top of it.
The device isn't something you're interested in - congratulations. Read another article then. If you're looking for phone only reviews, there's plenty of sites out there for those.
III-V - Friday, December 19, 2014 - linkWhat a sad world we live in, where we casually dismiss what others have to say as "trolling." And what makes you think he read the article?
I don't necessarily agree with him, but you're just being incredibly stupid.
Cinnabuns - Friday, December 19, 2014 - linkSo the OP's casually dismissive comment about a whole device category and the people who may be interested in it brought on a response in kind. This is sad how?
schizoide - Friday, December 19, 2014 - linkIt's a full, usable, x86 windows 8.1 tablet that regularly sells for $99 (and hit $79 on black friday!). It's not boring at all, it's downright astonishing that this thing even exists.