Projector review: Runco QuantumColor Q-750i - AVS Forum
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post #1 of 24 Old 02-16-2010, 01:46 AM - Thread Starter
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Projector review: Runco QuantumColor Q-750i
First LED projector for hometheater purposes



The eagerly awaited LED projectors have finally made their way into our laboratory, and we'll admit it: We're impressed. But our summary offers the first sign of trouble: We listed six plus points versus seven grumbles as is often the case with fledgling technologies, it'll take the industry some time to iron out the creases.

LED lighting technology has already made itself known on the TV scene, where it has largely delivered on its promises: more accurate colors, lower power consumption, and bright images. The hope is that it will bring many of the same characteristics to projectors as well as, for example, reducing the level of operating noise.

But with the Runco QuantumColor Q-750i, we've got complaints right across the board. The excellent colors only appear once you've tweaked the imperfect presets; the picture is extremely contrast-rich, but lacks brightness; the user manual is detailed and helpful, but the lens shift is impractical; de-interlacing is excellent, but there's no motion-enhancement technology. The list goes on



Crucially, the Runco failed to deliver the reduced power consumption you'd expect from LED technology at 192 watts on average, it barely consumes less than conventional models.

So while this represents a solid first offering from the LED projection sector, it's hard to find justification for the 15,000-dollar price tag. OK, that depends on what you value most, and many of our criticisms relate to performance rather than picture quality. In its defense, the Runco sets a new record with its ANSI contrast ratio of 620:1, and its in-picture contrast easily matches that of the best DLPs. The lens is crisp, and you can switch off the overscan.
Once you've calibrated the colors, therefore and there's little point in not doing so with a projector of this price you'll get an almost perfect picture: The video processing is highly accurate, the blacks are astonishingly deep, and the illumination remains uniform right up to the picture's edges.

Two picture-quality problems stand out: Firstly, you'll see color fringes left, right, and center if you aren't at the right viewing distance. Secondly, the images aren't very bright. The latter essentially means you're limited to a smaller screen two meters wide at most and will therefore only affect some users.

All in all, the Runco scored a solid 8 points out of 10 a score that says I don't bite, but perhaps not one that's worth 15,000 dollars. There's always the Samsung A-800 B, which we use as our reference projector, for 10,000 USD and it scored 0.5 points more than the Runco.

Read the full review of the Runco QuantumColor Q-750i at Televisions.com. Any comments on the device or our review are most welcome.

Florian Friedrich,
CEO of www.avtop.com, journalist and independent consultant from munich in germany.
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post #2 of 24 Old 02-17-2010, 08:23 AM
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Should YOU really be reviewing this product? "Lacks motion enhancement"? You mean, you want a video product to intentionally alter the source signal? "Imperfect presets"? How many people actually in the market for a Runco-level projector are not going to have the unit ISF calibrated? How many products shipped from a manufacturer can be preset accurately for every viewing environment they will enter? As far as grumbling about it being "very expensive", price and value are two different things. For the target consumer of this product, the cost factors much less into the value than the instant gratification of turning on immediately, the beautiful and reliably stable picture, the convenience of never scheduling lamp replacement appointments or the level of service they receive from a Runco-level dealer.
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post #3 of 24 Old 02-17-2010, 02:11 PM
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Wow looks like someone from Runco got their feelings hurt…..lol
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post #4 of 24 Old 02-17-2010, 04:49 PM
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I thought the review was fairly generous. I mean, now a days, who really says something like "with it's massive 2,000:1 contrast ratio"
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post #5 of 24 Old 02-17-2010, 05:52 PM
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By next year there will be many more LED projectors on the market and the prices will hopefully come down. The only problem I really have with this projector is it only has 600 lumens. Of course that is 600 permanent lumens over the life of the projector, but that is not very bright. I already am limited by screen size with my Marantz projector, which is also not bright. But I know that I would not be able to step down to an even lower light output. As it is now I am already in a bat cave. I can't possibly make my room any darker.
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post #6 of 24 Old 02-17-2010, 06:15 PM
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This pj is the great one,sure but the price is very scary when you can buy the decent pjs much more cheaper.
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post #7 of 24 Old 02-18-2010, 10:47 AM
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It really does stick out when one company out of a thousand allows the technical guys to dictate the spec numbers rather than the marketing department. 600 lumens? And how many lumens were the great CRT projectors putting out? And we all loved their black levels. 2,000:1 contrast? Guess you ran right out and bought brand-y $600 a/v receiver when they advertised 110 watts per channel? It is refreshing to see a company refusing to bow to industry practices of getting excited about false performance numbers. They're not selling to the Best Buy crowd. And, quite frankly, the Best Buy crowd shouldn't be weighing in on this kind of product. (And, no, I do not work for Runco. This just set me off enough to finally get in the commentary game. It's not the first time a "wine" piece" has been assailed by the "beer" crowd.)
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post #8 of 24 Old 02-18-2010, 08:25 PM
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What's wrong with the Best Buy crowd? I'm a Geek Squad employee, so that does not entitle me to install, look, or weigh in on a "wine peice"? It sounds to me that TelevisionsFlo made a fair review of this projector. What do you do for a living? Do you sell Runco? First you get your Runco Feelings hurt, now my Best Buy feelings are hurt. Thanks ha ha ha
P.S. And i have installed plenty of Runco PJ's, i hope you don't have nightmares!
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post #9 of 24 Old 02-21-2010, 10:13 AM
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So, bottom line... Are there better projectors in this price range with regards to a 110" Stewart screen in a 100% light controlled room?
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post #10 of 24 Old 02-21-2010, 11:57 PM
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TelevisionsFlo,

We at Runco would like to thank you for the generally positive review. I personally spent two years working on the Q-750 and am happy to see that some of its unique attributes impressed you. However, my team is a little concerned about some of the "grumbles" that you found, and would like an opportunity to try to offer some explanations of our philosophy as well as some corrections for the review.

First, I'd like to address the complaint about the brightness of the product. As you may be new to Runco products and the CSMS (Cinema Standards Measuring System) rating system we use, I want to explain exactly how it works. There are 2 lumens measurements on our spec sheets. The first, and the one that is probably the most meaningful to you, is the ANSI brightness measured with the projector calibrated to the home theater or CSMS standards. This rating according to our spec sheet is 450 lumens, which is a number I measured myself on an average unit and is pretty close to what you measured. The second number, which you quote as our "claim" of 700 lumens is actually only intended as a guide for comparison to other manufacturers' numbers and is not really meant to represent anything meaningful in the home. This number is a direct result of the trend towards poorly measured or exaggerated claims, and putting us into the same category as other manufacturers who can't meet their numbers is very frustrating to us when we're actually trying to correct the system. For your information, a so-called "1000 lumen" projector that you rated higher than ours was measured by Home Theater Magazine at 606 lumens in its brightest mode, and the manufacturer doesn't state anywhere to my knowledge how many lumens you'll really get when you set it up right. We're trying to change all that, and for more information on CSMS see http://www.runco.com/magic/csms-information/ or http://www.runco.com/_literature_47767/WSR_CMS_Story . I hope that you can help to spread the word about accurately reporting real-world specifications instead of hype.

Secondly, it appears that there is an error associated with your Personal Color Equalizer (PCE) settings that we feel contributed to some of your perceptions about color accuracy. It appears that although you used the CIE 1931 xyY color space for adjusting the PCE values, you adjusted the x,y values (using hue and saturation) but not the Y values (using level). Doing this from the default settings to try to get to BT.709 (the HDTV color standard) will result in colors that are too bright, and in some cases (red, for example) much too bright. The reason for this is the non-linear response your vision has to saturated colors otherwise known as the Helmholtz-Kohlrausch effect. Saturated colors appear brighter than non-saturated colors. This is the reason highly saturated objects appear to glow in most displays that have a larger color gamut than the capture device. Therefore if you want to make the color gamut significantly smaller then you also need to drop the brightness of the colors as well. This issue could explain some of the color artifacts you saw, even in dark scenes since color brightness and saturation are two separate things.

For your reference, here are the settings we would suggest to achieve BT.709 using the PCE. These settings were developed using a spectroradiometer and a NIST certified target. Since the viewing environment does have an impact (screens vary in the color of white more than our projectors do), these should only be considered a starting point. Note that we have published a reviewer's guide that contains this information and more. Please PM me if you would like a copy.

PCE settings for BT.709 (numbers are hue, saturation, level)
r: 125, 96, 71
y: 77, 85, 100
g: 48, 87, 92
c: 123, 48, 98
b: 82, 96, 95
m: 48, 80, 114
RSC: off

Once you set the level correctly for each color and get the x,y value right, there should be no perceptible color difference between the Q-750 and a reference BT.709 projector. The reds, for example, should not appear any more "intense and convincing" than any other well calibrated, BT.709 display.

This leads to our next recommendation that you at least try the Runco "Native" color gamut setting, since you (and most casual viewers) seem to prefer intense colors, and we believe they do have their place. The "Native" preset uses the entire available color gamut achievable with the LED illumination, allowing for about 90% more colors than BT.709 contains. But rather than simply mapping the colors directly to the larger gamut, we do everything in our power to make BT.709 sources look as correct as possible. This includes adjusting the secondary color points to better match the source, doing a 3D remap of colors close to skin tones, which otherwise would appear sunburned, pushing them back toward the BT.709 values (we call this Runco Smart Color or RSC), and making sure the color brightness does not cause the "neon" or glowing look for saturated colors. Once you do all this the results are quite compelling for sources that you would want to be represented in a greater color space than the standards allow such as outdoor events, concerts, and animation. I think that if you enjoy the "motion enhancement" frame interpolation of modern televisions, then you should at least appreciate the effort we went to here to try to put back something else that can sometimes be lost in the mastering.

I'd also like to ask about some of the trouble you seemed to have. Specifically, two items:

1) Have you contacted Runco about the trouble you were having with 1080i? 1080i through YUV inputs is supported, and is clearly shown in the manual. We test both flavors of 1080i50 (EU and Australia) and have not had any reported problems that could not be resolved. Have you tried setting the sync level in the fine sync menu? DC restoration is imperfect in many consumer sources, and often this control, which manually adjusts the sync detection threshold, fixes sync issues with analog sources.

2) Could you provide some detail about what you felt was "impractical" about the lens shift? I cannot find any details in the review. We've got +/-120% vertical and +/-25% horizontal lens shift (percent of half height/width, i.e. 0=centered, 100=lens at top or bottom of screen). It's more than most. I was wondering if maybe our nomenclature was again the issue. In our installation guide we define the shift in terms of screen heights/widths because it's easier for the installer to calculate where the screen goes. But this results in numbers that look like half of what others report in their specs.

To me it's all about numbers, but part of my job is communicating to anyone who needs to know what those numbers really mean. I apologize for not getting you more information before this review was made, but our team was unaware that it was going to press when it did. Please let me know if you have any questions about this product (or any other Runco product for that matter), or if you have suggestions to help make our documentation clearer.


Sincerely,

Bob Williams
Chief Product Architect, Runco International
www.runco.com
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post #11 of 24 Old 02-22-2010, 08:18 AM - Thread Starter
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Dear Bob Williams,
Thank you for your detailed feedback and your comments regarding our test methods. I hope everybody can see that we've made valuable comments on this projector's performance. To be fair to the Q-750, we've also reviewed a competitor in the LED-DLP market, and that model performed much worse. We might decide to publish a review of the other device soon.

I'd like to start my answer with a general description of how we review a device.
In general, we expect the devices to be delivered in a condition that requires as little professional tweaking as possible in order to deliver good quality performance.
I agree that there's more potential in this Runco projector if it is calibrated with the great effort that some experienced calibrators would be able to invest.
Even we could further optimize the device - we have all the necessary tools (such as a Minolta CS-2000) and the experience to do so. But this is against our philosophy; our reviews target end users, and we try to tell them what they can expect from a device as they'll receive it. Here's our general procedure, which we believe achieves that goal:

1. We try all presets that the projector delivers out of the box, and make notes. We even take measurements and try to find the most natural preset that way.
2. We calibrate brightness, contrast, overscan, and sharpness - things every enthusiast is able to do with a test disc such as HD Basics.
3. Using the best preset and the adjustments from step 2, we measure various indicators of the device's performance - brightness, contrast, etc. - and use these values to derive our ratings.
4. We check what can be done in terms of further calibration. We then discuss this within our review, as well as the effect of any picture options we can find.

I think that explains why our measurements turn out the way they do.
We measured the Runco's brightness at about 400 lumens and were able to increase this to more than 500 lumens by activating SatCo. Unfortunately, however, the SatCo mode delivers poor picture quality in terms of colors and gamut.
Luminance of primary colors and Helmholtz-Kohlrausch effect: We recommend that all manufacturers create one preset that is close to the studio standards or, in other words, is as neutral as possible. This should be the basis for any further calibrations. And it is possible to deliver accurate presets - one of the best examples I can mention here is the Samsung SP-A 800B, which we've also reviewed. It's not LED, I know - and I have a great deal of respect for a company that is actually able to build an amazing projector with a new technology like LED/DLP with no color wheel. But that doesn't mean we won't communicate criticism when we see weak points. I really hope everybody can see that.

We got the device from a Runco distributor in Germany and he was aware we would be reviewing it. In a situation like this we can expect it to show at least average quality. We did not receive any reviewing guidelines, and as much as I love to read such documents, that's the wrong perspective if I want to do a review for customers.

The lens shift flexibility is good - there's no question about that. We just had problems adjusting it. There was no motorized control and it was more than hard to reach.

Florian Friedrich,
CEO of www.avtop.com, journalist and independent consultant from munich in germany.
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post #12 of 24 Old 02-22-2010, 10:28 AM
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Quote:
Originally Posted by TelevisionsFlo View Post

...And it is possible to deliver accurate presets – one of the best examples I can mention here is the Samsung SP-A 800B, which we’ve also reviewed.

Could you comment on how one can deliver accurate presets without knowledge of what screen you're using? Or did you not use a screen when you measured the projector? Also could you clarify about using our presets? Did you use the "REC709" color gamut preset when you did your viewing evaluations? If so then the color brightness settings would be correct.
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post #13 of 24 Old 02-23-2010, 11:26 AM
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As someone who has calibrated many different brands and styles of home theater front projectors including the Q-750i (see link in my signature), I disagree with the idea that the Q-750i is not a bright projector. In my experience, most HT projectors put out an adequate amount of light only if they have a new bulb, are projected onto a smaller than average screen or a very high gain screen, and, most important, have not been calibrated in the most accurate picture mode. For example, sometimes I'll get an impressive 15-20 footlamberts of light output with a new bulb, in "dynamic" or "presentation" mode. However, as I start the calibration, I find that all picture presets except "theater" have serious inaccuracies. What's the light output like in "theater" mode? Oh, probably in the range of 6-8 fL... And what's going to happen in a year or two when the bulb has aged? Oh, it'll be down to about 5 fL or less...
I got over 13 fL from the Q-750i on a 1.3 gain, 114" diagonal 16x9 Stewart screen, after calibration. Compare that to the hypothetical situation above, and you'll see why I consider the Q-750's light output impressive.
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post #14 of 24 Old 02-24-2010, 07:22 AM - Thread Starter
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Bob and Chad,
Of course we use a screen! It’s the JKP affinity from Da-Lite. We’ve used and measured many screens within the last 10 years and this is my clear preference – neutral colors, no hotspotting, no visible structure that would affect a 1080p picture.

The room where we do the measurements is completely dark – there are no windows and all of the walls are black. In a situation like this, I’d say we’re really close to measuring the projector’s actual output.

I agree that there’s a color shift in any screen and that a projector should always be calibrated in the room where it’s supposed to stay.

When I say accurate colors in the presets I really mean we’re searching for a good basis for further – but hopefully slight – calibration in the customers’ homes.

But that shouldn’t mean that presets are allowed to be far from the broadcast standards. If the primary colors are way off from their supposed coordinates, I think it is fair to say that the preset is inaccurate. Below is the diagram of the Runco in its SatCo mode; Auto mode produces pretty similar results. No one can say that there’s a screen or situation which would change these coordinates to be accurate:





Chad, thanks for your valuable feedback, and of course you’re right: The Runco’s light output is acceptable for a good home-theater experience, and of course there are many projectors out there for which we couldn’t say the same.
What you say about the lamps losing brightness is correct as well. In fact, I don’t need to say any of this – you’re obviously a pro. But there’s a different point I wanted to make: I hear specs like 1000 lumens or 700 lumens all the time, but we measure a lot of projectors that output less than 500. Everybody expects LED to be much brighter than conventional lamps – but they're not. I don’t think buyers will be happy about that.

We measure projectors such as Sony’s VPL-HW 15 (>600 lumens), Panasonic’s PT-AE 4000 (>600 lumens), JVC’s DLA-HD 950 (>650 lumens) … I could continue for a while. The Samsung SP-A 800, with its excellent presets, also delivers >600 lumens. And when the light output reduces to 400 lumens on one of these projectors, I can replace the lamp and have a brighter image.

By the way: Another thing people expect for some reason is that LED projectors do not change their colors. The truth is: Over time, the intensity and even the spectrum of LEDs change with temperature and age; I’ve seen detailed research on this topic. Therefore, even LED projectors require regular recalibration. So please tell me: Where is their current advantage? I can replace a lot of lamps for the difference in price…
I really think LED has big potential but also a long way to go in order to being better than our current projectors.

Florian Friedrich,
CEO of www.avtop.com, journalist and independent consultant from munich in germany.
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post #15 of 24 Old 02-24-2010, 10:40 AM
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Quote:
Originally Posted by Bob Williams View Post

Could you comment on how one can deliver accurate presets without knowledge of what screen you're using?

It's hard for me to imagine that an accurate preset would look significantly compromised by an reasonable quality screen.

I've never seen a white screen that didn't look white in ambient light, meaning any color shifting is pretty small, and I've seen plenty of projector presets that are obviously biased toward green, blue, yellow, etc.

Noah
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post #16 of 24 Old 02-24-2010, 11:03 AM
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Florian,

You are right. I would complain myself if I measured the colors that you have on that chart. It's baffling to me since this is the only review we've had that's measured them so far off. Every projector is calibrated for color points to far more accurcay than that chart shows. Do you still have the serial number of that projector? I'd like to check it against the optical data from the line. And can you confirm that you used the CS-2000 and not a color meter to make the measurements? Color meters and LEDs generally don't work together yet.

Noah, my first thought was to blame the screen since that's one thing I don't have control over. The LED spectrum is broader than UHP and if you don't match the spectral response of your screen to this spectrum there's a chance that one of the colors will be muted causing a white point shift. I didn't see any data in the review that noted how bad the shift was, until now.

Quote:
Originally Posted by TelevisionsFlo View Post

...Another thing people expect for some reason is that LED projectors do not change their colors. The truth is: Over time, the intensity and even the spectrum of LEDs change with temperature and age; I've seen detailed research on this topic. Therefore, even LED projectors require regular recalibration.

I've been running two at my desk for more than 3000 hours and neither one requires any recalibration that I can see. The reason for this is that we have an internal tristimulus color sensor that calibrates the projector output continuously. This effectively negates both the temperature and time domain drift.
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post #17 of 24 Old 02-25-2010, 12:47 AM - Thread Starter
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Bob,

I can confirm we use a Minolta CS-2000; we stopped using anything else as soon as we realized the advantages for measuring special light sources and low light.

Incidentally, we were the first to use the CS-2000 with colorfacts, since we actually paid datacolor to support this meter. Right now it looks like we're moving back to the Minolta CS-10w software because we haven't seen further development in colorfacts and there are interesting new ways to measure colors more intensively than just doing CIE diagrams. As soon as we have news on this topic, I'll post it on AVS as well.

The serial number of the projector was: W8001E9420002

It is a good idea to do some auto calibration with an integrated sensor - I didn't realize something like this was integrated in the projector when we were reviewing it. I think this could work well for changing light intensity, but the only thing I wonder about is this: How did you manage to use a tristimulus to correct a shifting light spectrum? Tristimulus sensors usually have their own filter characteristics. In other words: If the spectrum of the red LED shifts, the sensor would indicate there's a corresponding change in light intensity. The lookup table for the necessary color corrections would therefore change the intensity of red, and that might result in color errors. I'm sure you found a smart way around it - I just can't imagine how. If you are able to talk about this in more detail, it'd be highly appreciated.

Florian Friedrich,
CEO of www.avtop.com, journalist and independent consultant from munich in germany.
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post #18 of 24 Old 02-25-2010, 02:50 PM
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For the LEDs that we use we have found that the dominant wavelength does not drift over time, and this is why a tristimulus sensor will work fine in keeping the balance of the colors correct, even over long periods. We've done more than 30,000 hours of total testing to confirm this. The dominant wavelength does vary (along with brightness) with current and temperature, but we monitor both of these parameters continuously and correct for the drift in real time. We have a temperature sensor right next to each LED, and in addition this allows much better thermal feedback than is possible in a lamp based system. So, although the cooling system looks more complicated to you than a UHP one, it's actually much simpler to me, and I've worked on digital projectors for the last 16 years. The current to each LED is driven digitally, and is extremely well controlled (as is necessary for use with DLP), much better than an equivalent color wheel. This leads to a higher bit depth on screen, and far less dithering than lamp systems.

Incidentally, I have also been using Colorfacts with my Minolta CL-200 and Photo Research PR650, but will probably be moving to CalMan shortly due to lack of support.
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post #19 of 24 Old 02-28-2010, 06:20 PM
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I am curious. How does the Q750i compare to the Runco LS-5 or the LS-3? Or, even the new JVC RS35? I am not aware of any local place to look at these within my city.
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post #20 of 24 Old 02-28-2010, 06:22 PM
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I should clarify. I do not have a screen but I have a dedicated room with complete light control. I am considering a Stewart screen. The room is about 23 ft long, 20 ft wide and 9 ft high. Will watch mainly DirecTV, PS3 and Bluray.
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post #21 of 24 Old 03-01-2010, 12:26 AM - Thread Starter
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Bob,

thanks for explaining. Really interesting approach to correct LED colors.

@Jtuttle: Sorry, we did not see the projectors right next to each other and I don't want to give buying advice. Please collect as many facts as you can and decide on your own. There's way too many variables in a puchasing decision like this to provide clear advice...

Florian Friedrich,
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post #22 of 24 Old 09-18-2010, 11:25 AM
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post #23 of 24 Old 09-21-2010, 10:07 AM
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Quote:
Originally Posted by Bob Williams View Post

Could you comment on how one can deliver accurate presets without knowledge of what screen you're using? Or did you not use a screen when you measured the projector? Also could you clarify about using our presets? Did you use the "REC709" color gamut preset when you did your viewing evaluations? If so then the color brightness settings would be correct.

Bob about one month ago, I visited the Listen UP store in Boulder to look at the Runco. I was not impressed with the projector at all and I was looking forward to being impressed. The image was dull and lifeless.

Another gentleman on this forum saw the same projector, the month before I did and thought it produced one of the best images he had ever seen.

I own a Sim2 Ht380 and and have been to Cedia twice when it was in Denver and so I know what a good projector should look like. I am wondering if someone changed the settings on the Runco at listen Up because even the salesman agreed that the image was not very impressive.
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post #24 of 24 Old 11-22-2010, 07:50 AM
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I visited Listen up in Denver this past weekend and when they told me the projector I was looking at was the Q-750 I was agast at how "bad" it looked. I really thought it was a different projector until I climbed on a stool and looked at the ID Plate. (Also not so impressed with the lack of knowledge about components from my sales rep.)

I was very disappointed.

I then went to Blu Note AV in Denver.

They have a Q-750 in a similar all blacked out light controlled room. They were playing clips from a WD live media tank in full HD. They only hung the projector 3 days ago are still setting up the room. However, the difference was night and day. The images were nothing short of amazing. The color depth and accurate colors, the dark level, shadow detail; everything that was missing from the listenup setup was present. They actually had the brightness turned down because in the 18 by 25 room on a 138" 2.35 screen 1.3 gain it was too much!

The setup of this and any projector makes a huge difference.
I would try a different dealer if you do not like the image for any projector.

I currently use a Vidikron Vision S-75 i.e. a rebodied Runco RS-1100. I love it, but I am looking for a 3 chip or tri color LED setup for a better picture.

David

"You buy a Ferrari when you want to be somebody. You buy a Lamborghini when you are somebody." - Frank Sinatra
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