NEC LT170 - Image Quality
Image Quality: Data (computer): Clarity and Color Handling
Clarity is excellent, with the lens having no problem providing a sharp image from edge to edge. Everything is nice and crisp looking, without the far more visible pixels of an LCD projector.
I observed the NEC LT170 at native resolution (XGA 1024x768) and it was excellent. I also fed the projector UXGA (1600x1200) and was impressed by the compression technology. As expected, smaller type became thick, and less than beautiful, but it handled my test spreadsheet with various fonts, sizes of type, and colors, extremely well. If you feed it that high a resolution on large type, like Powerpoint, any degradation is minimal and probably only detectable to the “front row.”
Click on Next page for Color Handling issues.
I better start by saying this is a DLP projector, and accurate color is a huge problem for most 1 chip DLP models (all DLP projectors under 30 pounds and $20K). This is hard to say. If accurate colors are important – you need bright reds, and bright yellows and you don’t want those reds to be dark wine colored, or those bright yellows to appear a muted, mustardy greenish yellow, then the NEC LT170, out of the box, isn’t the projector for you.
That is because the LT170, in its normal Presentation mode, gives you muddy greenish yellows and dark wine colored “bright reds”. The image to the left, should have a bright red background and a bright yellow pie slice in the front left, and should look like this:
Below you can see a shot of the projected image, with the screen of my Dell laptop, below, in the foreground. The color difference is obvious.
OK, that said, there is a real, easy solution, but it has trade-offs. First let me explain. For years most DLP projectors concentrate on those high lumen ratings. While I go into more detail elsewhere on the site, let’s just say that color suffers. DLP projectors are generally known for orangish, or dark reds when pure red is called for, and for yellows with lots of green. So understand, the NEC LT170 is one of perhaps 100 models that exhibit this problem. In the image above you can see what I am talking about. The yellow you see is a “pure” yellow (255 red, + 255 green), the red, is pure red (255 red). Now above the laptop is the projected image, and as you can see the “red” isn’t close and its dark, and the yellow has lots of green, and this is going to really upset some people. (This is the best I could capture with my digital camera, in life, the differences are even larger. If you like bright yellow text in your Powerpoint presentation, forget it! Unless: You change modes!!!
Click Next to learn how to make this work:
Changing color modes: On the LT170’s main menu, you can switch from presentation mode, to video mode – and voila – the reds are red, the yellows are yellow, everything is GREAT. EXCEPT: The projector is definitely less bright! I normally don’t bother measuring how many lumens a projector produces for the following reasons:
- They vary by unit to unit of the same model, because of the lamp, if nothing else
- Because a 10% variation of brightness really is barely detectable.
- Some brands are more conservative than others, but compared to other differences in projectors why quibble over a 100 lumens?
OK. This time I measured to see how much brightness was lost. Using a Minolta light meter, when measuring the whites (which is how you measure brightness), I found that brightness in video mode was only 47% of presentation mode, effectively reducing a 1500 lumen projector to just over 700 lumens.
Below, you can see two images - on the left, Presentation mode, on the right, Video mode, it is immediately obvious how much darker the whites and grays are in video mode.
It's more like whites and other colors have been brought down so that the reds and yellows now appear correct. Please, again, this exercise isn't just about the NEC LT170, but most small DLP projectors!
AGAIN, I must point out that this color handling is not uncommon for small DLP projectors, as the manufacturers are focused on the holy grail of maximum lumens, and they rate projectors in their brightest (in this case Presentation) mode!
The word to the wise, then, is if you need really bright, and great color on your presentation, you should probably be looking at LCD projectors, not DLP. But remember, as of today, there isn’t even a single XGA resolution LCD projector shipping that is as small as the LT170, and no XGA resolution LCD projector is as light!
So when push comes to shove, this NEC is a 1500 lumen business projector with (typically DLP) weak color, or a noticeably LESS bright projector with very good color!
Image Quality: Video
This NEC projector does a very acceptable job on video, with quality more than good enough for normal business applications. There is a choice between video mode and also Movie mode. If you want to watch a DVD, I’m not sure which is better, (ideal seems to be in between the two settings). The video mode has a higher Kelvin temperature (about 8000), vs. 5650 in movie mode. I did find the movie mode to have a slightly pale feel to it, and it appeared a bit low on the blues.
NEC's LT170 supports component video, as well as S-video and composite.
It’s more than adequate to set up in your house and run DVD’s TV or HDTV, although its definitely not a home theater projector. If home usage is very important to you, there are other small projectors you might prefer, but if everything else about the LT170 makes it desirable, and home theater is just a fringe benefit, then this is the right projector for you.