ANSI Lumens vs Color Light Output:
The Debate between LCD and DLP

Evan Powell, September 19, 2013


TEST # 2:
PROJECTORS REDUCED in BRIGHTNESS
with IMPROVED COLOR AND CONTRAST


IMPORTANT NOTE: The results of this test are valid only for these two particular models, not all LCD and DLP projectors in general. These two test units show image characteristics that are common in commercial/business projectors but not home theater. Furthermore, business-class DLP projectors can be designed with a variety of color wheel configurations that will produce different results. Typically, home theater DLP and 3LCD projectors are optimized for maximum color quality, not maximum light output, and the results herein do not apply.

Objectives:

In this second series of shots we see what happens when we calibrate both projectors for better color balance and contrast, and we set them to an equal ANSI lumen output.

Resetting the LCD projector. The calibration adjustments have taken most of the blue-green bias out of the picture. The contrast control was reduced substantially to allow highlight details to display properly. Brightness was reduced to deepen black levels. All of these changes were at the expense of image brightness. After adjustments the ANSI lumen output (white brightness) dropped about 24% from 4545 lumens to 3450 ANSI lumens.

Resetting the DLP projector. In the first test the DLP was putting out 5800 lumens of white light, and the color brightness was 1300 lumens, or about 22% of white. For this test we reduced the white light output to 3500 ANSI lumens to match the LCD, while keeping color values the same. This was done by reducing the "Brilliant Color" control, in this case cutting it in half. The end result was that color light was still measuring 1300 lumens, but it was now 37% of white instead of 22%. Increasing the percentage of color information relative to white improves overall color performance, as you can see in the following test images.

On a DLP projector is it usually an option to continue reducing the white component in the picture by further reducing the Brilliant Color control, and it can be taken all the way to zero. At zero, all of the light from the lamp is being directed through the color filters and none through the white filter. Accordingly, on this particular DLP projector in this configuration, ANSI white light lumens can be made to equal CLO color lumens, and both are 1300 lumens. The Brilliant Color control on a commercial DLP projector can usually be set anywhere between 0 and 10, and it allows you to seek the optimum trade-off between maximum lumen output (10) and maximum color performance (0) for your most important type of display content.



1. Monoscope Test Pattern

3LCD Projector                                                             DLP Projector

1. After calibration, most of the blue tint that was obvious on the LCD projector in the first test has been eliminated. These are not home theater projectors so a perfectly neutral grayscale is difficult to achieve with the high light output. The objective was to move the LCD as close to a neutral gray scale as possible while still maintaining substantial light output. There is still some subtle blue bias in the mid-tones, but it is not nearly as blue as it was. The green tint in the white is gone. The contrast control was reduced substantially to bring highlight details back into the pictures.

Meanwhile, the DLP projector is now set to an ANSI lumen white output of 3500 lumens to match the 3LCD. The highlights show a slightly warmer than neutral tone, and the lower light levels still contain a bit more green than is ideal. But the two projectors are essentially equal in white light output. Color balance, while not home theater perfect, is well within tolerable limits for commercial applications.

Color Bar Test Pattern

3LCD Projector                                                             DLP Projector

ColorBars

2. With these calibration adjustments, the color bar test patterns look somewhat improved. The LCD projector is slightly more saturated, the DLP is slightly brighter than it was. The most obvious difference between the two projectors is still that the colors on the LCD are brighter across the board. Red in particular remains substantially weaker on the DLP than on the LCD. This weakness in red will show up in a variety of ways in real life images.


So enough of test patterns, let's move on to see what all this looks like in actual photographs...







3. Colored Paper

3LCD Projector                                                             DLP Projector

3. In this high saturation image the LCD projector displays an obviously brighter picture. However, if one focuses on the white strip, the DLP projector appears to be higher in contrast.

The apparent contrast advantage of the DLP comes from two factors we've already seen--the reduced color brightness increases the difference between white highlights and color subject matter, and DLP projectors generally have a greater range of white to black in a given scene than do LCD projectors.

These two projectors are both rated at 2000:1 Full On/Off Contrast. Unfortunately the Full On/Off Contrast spec that vendors typically publish says nothing about the ratio of black to white in a given scene. For that we would need the ANSI Contrast spec. Very few vendors publish ANSI Contrast numbers since they are usually well below 1000:1, and therefore have no marketing sizzle.

4. Pastels

3LCD Projector                                                             DLP Projector

In this scene of pastel colors we see the same trade-off as in the higher saturation scene of colored paper. The LCD projector is once again brighter, and the DLP's image is not as bright but is higher in contrast and has more apparent color saturation. The LCD's blue values are double the brightness of the DLP, and its yellows are 50% brighter. But the lower color brightness on the DLP renders the colors darker, so they look higher in saturation and the picture looks higher in contrast. So here the lower color brightness actually ends up producing a more pleasing, if less accurate image.

Since the white component has been reduced substantially on the DLP, color light as a percentage of white has been increased. This improves color accuracy. In this configuration, the blue ball in the center is now blue rather than teal as it was the first time. Yellow is still off a bit, but these errors are not as pronounced as they were in the first test. Reducing the "Brilliant Color" control tends to improve color on many DLP projectors as it does on this one.

5. Fall Color

3LCD Projector                                                             DLP Projector

5. This is another example of low saturation colors. The LCD projector is rendering the scene with more accurate color and brightness balance. In the actual theater the 3LCD is obviously brighter, though the process of taking a screen shot and reproducing it on a monitor tends to neutralize the apparent difference. But the darkening of the red foliage on the DLP (which is an error) creates higher contrast. Many people might say they prefer the way it is being displayed by the DLP due to the higher contrast.

6. Pencils

3LCD Projector                                                             DLP Projector

6. Recall that prior to calibration the LCD projector was interpreting the background of this image as blue. With the color adjustments, it does a much better job seeing the background as gray, though it retains a more subtle bluish tint.

In this image the LCD has an advantage in color brightness and accuracy. According to the spot meter, the yellow pencil is 50% brighter on the LCD than on the DLP, and it is rendering a reasonably satisfactory yellow. The DLP's yellow has a shift toward olive once again. The orange pencil is double the brightness on the LCD compared to the DLP. Here again the DLP shifts orange toward brown though not as badly as in the first test; in this image the orange pencil still retains an orangish hue, where before it was fully brown.

On the other hand, the DLP projector again shows greater apparent contrast and saturation. The darker colors look higher in saturation, while the white reflection glare on the pencils is the same brightness on both projectors. So the greater range in brightness between the white glare and the darker colors on the DLP contributes to higher contrast.

In short, both of these projectors do better with this image after calibration, but the LCD is ultimately the brighter and more accurate of the two.

7. Bread and Fruit

3LCD Projector                                                             DLP Projector

7. The weakness of red on the DLP projector is quite obvious when subject matter of high-saturation red is a dominant element in the image. All commercial DLP projectors may not manifest a weakness in red to the degree that this one does. But we have seen this on other DLP models and it is not uncommon. If the content you plan to display uses a lot of high saturation red (particularly vital for eye-catching red highlights in digital signage and advertising applications), this is a limitation that should be explored prior to purchasing a projector.

Also notice in this scene that white values (the bread) are about equal in the two images, whereas the color values are quite different in brightness. The LCD does a better job in this scene of producing a more natural balance of illumination.

8. Woman and Bamboo

3LCD Projector                                                             DLP Projector

8. This image illustrates the subtle effects of a weak red channel. The LCD image in this scene is brighter, but only by about 20% so not enough to make a difference in most situations. The larger problem here is accurate flesh tones. Lighter skin tones require a bit of red to make the skin look naturally warm, or pinkish. The weakness in the red channel on the DLP projector shifts the young woman's skin tones toward a less attractive gray-green hue.

If you intend to display portraiture or any other frequent display of flesh tones, it is important to avoid this particular flaw. It can be avoided on most DLP projectors by turning the "Brilliant Color" control off or to very low values, or by choosing a DLP projector that has a much smaller white segment in the color wheel than they often do. You may give up some light output, but the display of pleasing and accurate skin tones is vital when people constitute an important part of the content to be presented.

9. Cityscape, Night Scene

3LCD Projector                                                             DLP Projector

9. Color is never the only issue in picture quality. Other contributing factors include dynamic range, black levels, digital noise, color uniformity, and image sharpness. DLP projectors can often outperform LCD on some or all of these aspects of image quality. This DLP projector outperforms its LCD counterpart in dark scene detail and black level, which is not unusual.

Now that this LCD projector is calibrated, this scene looks far better than it did in its maximum brightness mode. Its black level rivals the DLP without losing much detail. Brightness can be reduced even further for a deeper black at the expense of shadow detail, if that were desired.


Previous Page
TEST 1: Uncalibrated
Next Page
Concluding Thoughts
Contents: Introduction Executive Summary Test Set Up TEST 1: Uncalibrated
  TEST 2: Calibrated Concluding Thoughts

Reader Comments(14 comments)

Posted Sep 5, 2014 12:48:01 PM

By David

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One of the most comprehensive, well explained articles explaining (and showing) the differences in DLP and LCD color and brightness quality. Seeing the images side by side really helps...

Posted Jul 24, 2014 8:59:13 AM

By Home Theater Install

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AV_Integrated: I agree with your comment regarding RGB/RGB color wheel providing most accurate color display. I believe the Optoma HD30B is the model you need to compare to the W1070.

Posted Jul 16, 2014 8:34:52 AM

By AV_Integrated

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It would be excellent to have you guys run through this test again using three of the most popular 'cheap' home theater models. The Optoma HD25-LV (or similar) with a 2x, 6 segment (RGBCWG or RGBCYM) color wheel, the BenQ W1070 with the 6x RGB/RGB color wheel, and a Epson 2030 or 3020 model.

There's a lot of talk out there about the brightness specification of the Optoma models, but it seems that real world viewing won't actually allow it to deliver the same brightness, post calibration, or with normal use, that the W1070 is capable of delivering, and the cheaper Epson model may not be able to match either in regards to contrast, but may do very well elsewhere.

While dedicated home theater users may typically not care, for those with family room environments, non-dedicated spaces, or larger screens, the importance of getting post-calibration real world color brightness figures really seems like an important specification that can't be found anywhere else.

Similarly, it would be great for all reviews to include color wheel information and color wheel speed at differing input frequencies as most projectors don't have the same color wheel speed for 60hz content as they do for 24hz content.

Thanks for a very interesting read, even if I am getting to it a bit late!

Posted Jun 23, 2014 2:21:34 PM

By Bob

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This could happen but is extremely rare.

Posted Jun 23, 2014 2:20:23 PM

By Bob

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All the projectors you are considering have their merits. First consider your requirements - how much ambient light is in the room, what type of screen are you using, what size screen and what will you be watching?

For a dedicated home theater you don't really need 3000+ lumens unless you will be watching a lot of 3D content....most people don't after watching a few movies in 3D.

I do recommend moving up to 1080p, if within your budget. You may find that 3000+ lumens is too bright for a dedicated home theater. Also, look for a projector designed for home theater - for instance a color wheel with a white segment may focus on brightness instead of saturated colors.

Posted Jun 23, 2014 2:03:15 PM

By Bob

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Projection technology has been around for a long time now - both DLP and LCD projected images look great. I feel confident recommending both technologies without hesitation. If a customer is not happy with an image after adjustment, most projector manufacturers will assist customers or swap out the projectors.

The only companies really disputing this fact are the manufacturers of LCD panels and DLP chips. The DLP camp has not run a negative campaign for years, but this year at INFOCOMM, an LCD manufacturer had a side by side demo calling out the benefits of CLO. In the demo, both projectors were displaying images in high bright mode and both images were over-driven, and were not really acceptable, but the DLP image looked worse. When the settings were changed to a more user friendly mode, both projectors looked pretty good.

It seems that some projector manufacturers are determined to shift market share from one display panel technology to another. This might be a great idea in a growing market but the PJ market is relatively flat.

These component manufacturers should focus on finding ways to grow the PJ segment instead of shifting share.

At INFOCOMM there were several amazing LARGE screen displays that called out the benefits of projectors, including edge blending, LED, laser, interactivity, and digital signage. The industry needs to focus on the big picture and not components.

Posted Jun 11, 2014 10:36:19 AM

By Joshua

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Hey all, I just purchased a 730hd Epson with lCD and this is my first purchase of a projector. I'm wondering if I made a mistake for 2 reasons. First, it's 720p and does not do 3d. Second, will the LCD remain viable over time and product the best image? I'm considering swapping it out for Optoma DH1011 or a ViewSonic PJD7820HD.

Question is, will the DLP look as good as the 3 LCD from the Epson?

Posted Jun 4, 2014 11:25:00 PM

By Michael Miller

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And if you run the test after 3 years your DLP projector will have lovely sparkles all over it from the failed DMD chip.

Posted May 12, 2014 12:26:32 PM

By Lee

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Chris, I don't know where you are getting your information. First - no one knows exactly which LCD models have inorganic LCD chips, and many brands don't disclose this- so why you would you say that the #1 subject on the Projector Central forum is not relevant to a consumer anymore? Secondly, on what basis are you making the claim that DLP projectors use "lower quality parts"? Based on the Amazon top seller list today, the top four 1080p projectors are DLP, before a LCD projector is ranked. I have a hard time believing that they have "lower quality parts", when there are also sub $1k 1080p LCD projectors as well. I think the article shows that the image quality of a projector is not defined by a single spec, and this is where reviews by both this site and consumers really help consumer's decision making on a projector - regardless of the technology.

Posted May 5, 2014 9:40:36 AM

By chris

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Many LCD chips today are inorganic, so I don't know how relevant that is today, and I would also figure a true head-to-head test would be difficult as there are so many other factors, whether testing with brand new units, or older units with thousands of hours on them. For instance, it's been my opinion that most entry-level projector that use lesser DLP chips don't look as good (overall) as their LCD counter parts. Consider the Epson 5030UB and/or 6030UB and the Panasonic PT-AE8000U when compared to anything buy BenQ, Optoma, Vivitek, etc. for the same/ similar money. There are longevity issues, maintenance issues, and other set-up parameters to discuss as well, but in general... simply talking to the light output and it's perception in the image quality of the projector... I think LCD wins every time over DLP. When you start climbing the food chain a bit and start considering "better" LCOS units and DLP units, this changes some, but the bulk of the projectors purchased for home use are well under $5k and for those buyers it's hard to surpass the overall image quality of the LCD projectors offered in this pricing category.

Posted Feb 25, 2014 9:59:17 AM

By TimN

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It would be interesting to take this same evaluation and conduct it a year later or with say a 1000 hours on the projectors. Change the lamp and run the same tests again.

I'm guessing you would not get the same results on the LCD projector due to color decay from the organic compound in the LCD panels (chips). You could have a severely yellowish image from color decay and still meet the CLO ANSI lumen specifications.

This is the big advantage in my opinion for DLP projectors over LCD projectors. Same color from one year to the next regardless of how many times the lamp is changed.

Posted Oct 30, 2013 10:51:22 AM

By Darin

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Definitely some interesting results and comments. Thanks. I'm wondering if for Powerpoints in Test 1 you looked at anything like pie charts or line graphs that use multiple colors. Given the results in the Color Bar Test Pattern it might be interesting to see how Powerpoint presentations that are trying to differentiate information by color would tend to fare on each in a room with lots of room lighting on.

Posted Sep 19, 2013 2:04:23 PM

By Evan Powell (Editor)

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JVC's D-ILA and Sony's SXRD are both versions of LCoS. The projectors they make with this technology are three-chip units, so white light and color light values will always be the same on them. Sony quotes the CLO spec and JVC does not.

Posted Sep 19, 2013 1:23:38 PM

By Gary Hatch

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What would a Dila/LCoS (JVC/SONY) projector fall in this mix?

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