JVC DLA-RS1 Owner's Thread - Page 3 - AVS Forum

Rob Tomlin · 03-02-2007, 02:04 PM

Quote:

Originally Posted by gregr

Bad for me. I'd like to skip writing the review and just start talking about the projector here on the forum. But I don't have that option.

We do realize this, and therefore greatly appreciate the fact that you have posted regarding the initial problem re the processing of RGB signals as this allows JVC to have the opportunity to address it sooner rather than later.

gregr · 03-02-2007, 02:07 PM

Quote:

Originally Posted by Spizz

Is JVC also addressing the overscan problems-

http://www.cine4home.de/tests/projek...HD1/Bild62.jpg
http://www.cine4home.de/tests/projek...HD1/Bild63.jpg

What are the formats used for those two pictures? Are they 576i and 576p? Or 480i and 480p? Which picture shows which? They are obviously AVIA test patterns from a DVD player, so overscan depends on the DVD player. i.e. it's not the best indicator of the projector's actual performance. Are they taken with digital signals or analog signals? There can be a big difference.

What is it you actually want to know?

lovingdvd · 03-02-2007, 02:13 PM

Greg - since many of us will be calibrating our units very shortly, could you please comment on how the RGB controls work compared to the offset controls.

Someone reading this at first glance may think the answer is obvious - gain controls the high end, offset controls the low end. However its been stated many times that the offset control does not do what one things it would do, and actually impacts the entire range.

So I was hoping you can elaborate on this a bit. Specifically, if the offset control impacts the whole range, and so does the RGB control, that do these controls serve any different purpose on this unit, and if so, what? When doing your calibration was it sufficent to use just the RGB control or was it a combo of RGB and offset? Thanks!

Mark Petersen · 03-02-2007, 02:37 PM

Quote:

Originally Posted by gregr

What is it you actually want to know?

I know you can't tell us too much in advance of your review and you've mentioned that it's pointless to rate a projector on a 1 to 10 scale. But can you tell us if you like it "a lot" or just "a little?"

Btw, if you need a set of intra-image contrast patterns to test the RS1, just let me know

GlenC · 03-02-2007, 02:38 PM

Quote:

Originally Posted by lovingdvd

Greg - since many of us will be calibrating our units very shortly, could you please comment on how the RGB controls work compared to the offset controls.

Someone reading this at first glance may think the answer is obvious - gain controls the high end, offset controls the low end. However its been stated many times that the offset control does not do what one things it would do, and actually impacts the entire range.

So I was hoping you can elaborate on this a bit. Specifically, if the offset control impacts the whole range, and so does the RGB control, that do these controls serve any different purpose on this unit, and if so, what? When doing your calibration was it sufficient to use just the RGB control or was it a combo of RGB and offset? Thanks!

The RGB level controls in User 1 and User 2 allow custom color temp. The RGB offset adjusts the levels for the preset color temps (Low, Medium, High). You can fine tune Low/Medium to D65. The controls are linear and the actual gray scale for each step is controlled in the LUTs.

Rob Tomlin · 03-02-2007, 02:51 PM

Quote:

Originally Posted by Mark Petersen

I know you can't tell us too much in advance of your review and you've mentioned that it's pointless to rate a projector on a 1 to 10 scale. But can you tell us if you like it "a lot" or just "a little?"

Oh yeah, cuz telling us if he likes it "a lot" or just "a little" is much more accurate than giving a 1 to 10 scale rating!!!

Mark Petersen · 03-02-2007, 02:57 PM

Quote:

Originally Posted by Rob Tomlin

Oh yeah, cuz telling us if he likes it "a lot" or just "a little" is much more accurate than giving a 1 to 10 scale rating!!!

Well when I started writing my post it said, "If the RS1 were a woman how would you rate her". But the responses that I came up with were sure to devolve this thread into something similar to Tryg's CES booth babes list so I resisted temptation and went for simplicity instead.

Rob Tomlin · 03-02-2007, 03:11 PM

Quote:

Originally Posted by reio-ta

I hope there is some "softness" to the image, otherwise just get DLP. That's why I like LCOS, it's a bit soft and at the same time sharp without the over digital look that DLP gives. I like how film looks. LCOS gives the closest representation to film and yet still have awesome contrast ratios and blacks. I look forward to comparisons by anyone who has seen the Ruby and what the RS1 looks like compared to what others have called "silky" when viewing material on the Ruby.

Semantics are definitely a problem here. I have discussed this before....the problem with the word "soft" is that it implies a lack of sharpness and ability to resolve fine detail. This is obviously NOT something that I am interested in!

However, regarding the "digital look of DLP", I agree that it can look overly processed and "digital" for lack of a better word, and this is also NOT something I want. I want it all. I want sharpness without looking harsh or "digital". DLP dithering is also something that bothers me greatly, so LCOS should satisfy me in that regard.

Spizz · 03-02-2007, 03:18 PM

Quote:

Originally Posted by gregr

What are the formats used for those two pictures? Are they 576i and 576p?

The 1st with 25 pixels cut of the side was 576p and the 2nd was 576i where 40 pixels were cut of the sides. I believe it was done via HDMI.

Quote:

What is it you actually want to know?

I take it you don't test for PAL material so does this issue also occur with 480i and 480p? Lastly is there an option forthcoming to turn this off.

lovingdvd · 03-02-2007, 03:18 PM

Quote:

Originally Posted by GlenC

The RGB level controls in User 1 and User 2 allow custom color temp. The RGB offset adjusts the levels for the preset color temps (Low, Medium, High). You can fine tune Low/Medium to D65. The controls are linear and the actual gray scale for each step is controlled in the LUTs.

Thanks. However I believe this directly contradicts what cine4home and Jason reported. IIRC they both specifically stated that the preset controls low and medium could not be changed, and that one needed to start from scratch with the user 1 / user 2 controls to customize grayscale.

GlenC · 03-02-2007, 03:38 PM

Quote:

Originally Posted by lovingdvd

Thanks. However I believe this directly contradicts what cine4home and Jason reported. IIRC they both specifically stated that the preset controls low and medium could not be changed, and that one needed to start from scratch with the user 1 / user 2 controls to customize grayscale.

You cannot change the L/M/H color temp in the CT Menu, however the offset is to correct those. Once the bulb settles in or gets changed, there needs to be a way to adjust the color temp. With the "offsets", if "Middle" is supposed to be D65, then correction to D65 can happen, but it is linear and global over L/M/H. If Middle is set to D65, you cannot change Low or High.

Hughman · 03-02-2007, 03:47 PM

Quote:

Originally Posted by GlenC

The RGB level controls in User 1 and User 2 allow custom color temp. The RGB offset adjusts the levels for the preset color temps (Low, Medium, High). You can fine tune Low/Medium to D65. The controls are linear and the actual gray scale for each step is controlled in the LUTs.

Though my pj is not in my hands yet I was anticipating this would more than likely be the case, the other reviewers attempted to changed the presets with the rgb's available in the preset window. It's the only scenerio that makes any sense, redundant rgb controls does not.

I'd like to hear Jasons and cine4homes thoughts on this.

Cam Man · 03-02-2007, 04:23 PM

Good news for me today! I was told this morning by my distributor to only expect one RS1 from this first wave, but two arrived this afternoon. These are the first two in the Rocky Mountain region. I must keep one for demo purposes

but since my current projects aren't far enough along to need a projector yet, the other RS1 is available if any of you guys are interested or near AZ. PM or email at [email protected] if you're looking for one.

I have to jump on the road for a few hours, but will check in later.

Cheers

smithfarmer · 03-02-2007, 09:47 PM

Quote:

Originally Posted by Jerry Gardner

Wow! Is it really that soft? The LotR shot, in particular, looks very soft.

Let's not jump to conclusions here.

There could easily be quite a few different reasons for any shot to appear soft and those reasons have absolutely nothing to do with the pj.

erkq · 03-02-2007, 10:26 PM

Quote:

Originally Posted by smithfarmer

Let's not jump to conclusions here.

There could easily be quite a few different reasons for any shot to appear soft and those reasons have absolutely nothing to do with the pj.

I agree. How can you tell anything about the sharpness of a 1080x1920 display through a 600x800 picture?

steppen · 03-03-2007, 12:04 AM

Quote:

Originally Posted by Thunder

Other advantage is longer throw works better with an anamorphic lens

With the RS1 having a very large (+/- 80% of screen height) potential vertical lens shift, it would seem that placing it at the extreems of the range could increase the image distortiion produced by an aanamorphic lens. Intuitively, it would seem that the closer to the optical axis of the screen that the projector is mounted the better.

Has anyone looked at the issue of lens shift and anamorphic lenses?.

PJG

noah katz · 03-03-2007, 01:39 AM

"Pixels aren't "square" or "rectangles" as engineers seem to think. Each pixel is a point sample."

That may be true in information space, but not in physical space; the information in the sample is displayed over the full area of the pixel.

I've seen a couple of G15 DILA's up close to the screen, and while the edges of the pixels were hard to see because the grid was a lightish gray, the pixels are most definitely square.

dazzerxxx · 03-03-2007, 02:08 AM

Quote:

Originally Posted by reio-ta

When I think of soft, I think of the two pixels blending together, sort of how "wobulation" with RP DLP works. What I don't like is that sort of effect to gain a softness also adds blur. You don't have to have blur to have pixels blend and have that nice soft picture that comes with film. LCOS has that property where the center of each pixel is brighter and slowly dims to the boundary of the pixel in a circular pattern. Pixels aren't "square" or "rectangles" as engineers seem to think. Each pixel is a point sample.

EDIT

It's not perfectly the way I described with D-ILA but it's a lot better than with DLP or LCD that's for sure! The pixels sort of make "ovals" within each grid I'd say, rather than spheres.

I guess there is no right or wrong here just personal preference. Some will claim DLP harsh, course, digital etc whilst other will claim DILA, LCOS, SXRD is soft, blurry etc. No amount of response and counter response is going to provide a definitive answer on this subject.

My advice to anyone is go and see the different technologies and PJ's in action. I know from personal observation that the level of detail varies between different 1080 PJ's even when they are based on similar technology.

I know folks who prefer the image on a display because of "ringing" added during the video processing. They tell me it looks sharper compared to the image that doesn't have it.

Dazzer

dazzerxxx · 03-03-2007, 03:46 AM

Quote:

Originally Posted by reio-ta

Just so we're clear that I'm thinking of the same ringing. The hair around lady liberty on the left side is "ringing". Why would anyone want that? Is this person you know missing a few too many brain cells?

I think that is an extreme example. The Fuji 50XHA40US Plasma AVM processor adds "ringing/edge enhancement" to the image. Compare a 1:1 pixel mapped imaged from a Lumagen to a 720p/1080i signal direct to the panel. Some say the image is "more defined" or "sharper" when fully processed via AVM. Others don't like the artificial effect of "ringing/edge enhancement" produced by AVM.

I've spent time with Sim2 three chip and single chip products. There is no less detail in certain LCOS PJ's. Not all DLP are equal and the same applies to LCOS.

My advice to anyone is go see the products first hand and do a thorough demo with familiar test material. Then decide for yourself if there is any missing detail or the image is course or if you prefer the look of one tech over the other. That's the best use of brain cells when comparing products.

Dazzer

VirusKiller · 03-03-2007, 06:53 AM

Question for Greg Rogers (in the correct thread I hope!

).

You talked about projectors accepting RGB inputs, converting to YCbCr color-space for internal processing and then back to RGB to drive the panels. I didn't realize this, but it makes sense.

Do you know what the RS1/HD1 does with a 1080p RGB signal? With 1080p24, I know that the Gennum in the RS1 frame doubles, so presumably RGB -> YCbCr -> RGB conversion still occurs. But what about 1080p50 and 1080p60? According the Alex Kobayashi (the designer) it's still got to drive the panel at 2x 48p, 2x 50p or 2x 60p. I'm not sure where this processing occurs however.

In short, if I'm feeding 1080p24/50/60 to the RS1 with a Lumagen scaler, would you agree that a YCbCr 4:4:4 feed would minimize conversions (particularly if sources are also YCbCr)?

Thanks.

Edit: I guess (with HDMI 1.2) 10-bit YCbCr 4:2:2 is also possible from the scaler. I wonder what the ramifications would be of feeding the Lumagen 4:2:2 8-bit sources, have the Lumagen upsample to 4:4:4 for 10-bit processing, and then downsample to feed the PJ at 4:2:2 10-bit?

Cine4Home · 03-03-2007, 07:11 AM

Quote:

Originally Posted by Hugh2

Though my pj is not in my hands yet I was anticipating this would more than likely be the case, the other reviewers attempted to changed the presets with the rgb's available in the preset window. It's the only scenerio that makes any sense, redundant rgb controls does not.

I'd like to hear Jasons and cine4homes thoughts on this.

It is true.. with offset, you can actually correct the Middle and Low settings. however, these controls are by far not as precise as the ones in Color Temp. So we favorise adjusting Color-Temp.

Regards,
Ekkehart, Cine4Home

Cine4Home · 03-03-2007, 07:14 AM

Quote:

Originally Posted by gregr

What are the formats used for those two pictures? Are they 576i and 576p? Or 480i and 480p? Which picture shows which? They are obviously AVIA test patterns from a DVD player, so overscan depends on the DVD player. i.e. it's not the best indicator of the projector's actual performance. Are they taken with digital signals or analog signals? There can be a big difference.

What is it you actually want to know?

It is all written in the review. The source has no Overscan, so it is not the player. The patterns are not from AVIA...

Regards,
Ekkehart

mdrew · 03-03-2007, 09:00 AM

This projector is on my short list for upgrading to a 1080P unit, as with the other four or five thousand folks reading these threads.

I have a concern though. I just bought a Stewart Firehawk screen about two months ago because I like to have a lamp on every once in a while if the buds are over watching a game. (small area with a bunch of guys in the dark drinking beer just ain't cool). The throw ratio is 1.8 / 1, it's ceiling mounted and the screen is 96 X 41 in a constant image height set up.

So my concern is Jason states in his review that a grey screen may not be a good choice for use with this projector. This screen wasn't exactly cheap and I don't want to buy something else just for this particular projector. Anyone have any thoughts on this? Should I steer away from the RS1 and look harder at a different projector?

Bob Sorel · 03-03-2007, 09:07 AM

Quote:

I guess there is no right or wrong here just personal preference. Some will claim DLP harsh, course, digital etc whilst other will claim DILA, LCOS, SXRD is soft, blurry etc. No amount of response and counter response is going to provide a definitive answer on this subject.

While "right" and "wrong" can be subjective terms in this usage and therefore open to opinion, one type of pixel structure matrix versus another can certainly be proven to be more "accurate" at reproducing the original video content than the other.

Tube amplifiers, with their IM and harmonic distortion and rolled off high end, can be preferred by some people over the sound of well designed solid state amps, so in that respect there is no "right" or "wrong" amp choice either. But once again one is most definitely a more accurate representation of the original source material than the other.

Rob Tomlin · 03-03-2007, 09:08 AM

I would like to put information in the first post regarding mounting requirements for throw distance and offset, but I want to make sure that I get it right before doing so.

The DLA-RS1 has a 80% vertical and 34% horizontal shift lens. What does this mean in practical terms? I do not recall if the RS1 must be mounted within the screen height, or can it be above? Is the 80% measured from the center of the screen? I.e., if you have a 5 foot tall screen, 80% of that is 4 feet. Measuring from the center of the screen (2.5 feet from the top) would mean the RS1 could be mounted 1.5 feet above the top of the screen? Is this correct?

I believe the 34% horizontal shift means you can shift 34% of the image width from side to side? So if you have a 100" wide screen, the projector could be mounted off center by as much as 34 inches? (that doesn't seem right?)

The manual zoom lens has a range of 1.4:1 ∼ 2.8:1. Multiply this number by the screen width to determine how far from the screen the projector can be mounted. If your screen is 100" WIDE, you could mount the RS1 between 140 inches and 280 inches from the screen. Correct?

Tryg · 03-03-2007, 09:15 AM

Quote:

Originally Posted by Rob Tomlin

Correct?

yes

Bob Sorel · 03-03-2007, 09:18 AM

Quote:

The DLA-RS1 has a 80% vertical and 34% horizontal shift lens. What does this mean in practical terms? I do not recall if the RS1 must be mounted within the screen height, or can it be above? Is the 80% measured from the center of the screen? I.e., if you have a 5 foot tall screen, 80% of that is 4 feet. Measuring from the center of the screen (2.5 feet from the top) would mean the RS1 could be mounted 1.5 feet above the top of the screen? Is this correct?

From he way that that reads, I would expect that if you had a 100" X 100" screen and mounted the projector dead center in both the horizontal and vertical planes that you could shift the image up or down by 80" and from one side to the other by 34". Maybe that is incorrect, but that is how it sounds to me.

"Yes" on the other 2 questions.

MikeSRC · 03-03-2007, 09:28 AM

Quote:

Originally Posted by Rob Tomlin

The DLA-RS1 has a 80% vertical and 34% horizontal shift lens. What does this mean in practical terms? I do not recall if the RS1 must be mounted within the screen height, or can it be above? Is the 80% measured from the center of the screen? I.e., if you have a 5 foot tall screen, 80% of that is 4 feet. Measuring from the center of the screen (2.5 feet from the top) would mean the RS1 could be mounted 1.5 feet above the top of the screen? Is this correct?

I believe the 34% horizontal shift means you can shift 34% of the image width from side to side? So if you have a 100" wide screen, the projector could be mounted off center by as much as 34 inches? (that doesn't seem right?)

When you see shift percentages, 50% means that the center of the lens could be opposite the edge of the screen (since the percentages start with the projector in the center of the screeen, it's 50% of the width or height from each edge). So, 80% vertical means that the center of the lens can be as much as 30% (of the screen height) below the bottom of the screen or above the top of the screen. Same goes for horizontal. Of course, usually the more you use in one direction limts the amount you can use the other direction, so using 80% vertical will probably not allow for any horizontal shift.

keithsimp · 03-03-2007, 09:36 AM

Quote:

Originally Posted by Rob Tomlin

I would like to put information in the first post regarding mounting requirements for throw distance and offset, but I want to make sure that I get it right before doing so.

The DLA-RS1 has a 80% vertical and 34% horizontal shift lens. What does this mean in practical terms? I do not recall if the RS1 must be mounted within the screen height, or can it be above? Is the 80% measured from the center of the screen? I.e., if you have a 5 foot tall screen, 80% of that is 4 feet. Measuring from the center of the screen (2.5 feet from the top) would mean the RS1 could be mounted 1.5 feet above the top of the screen? Is this correct?

I believe the 34% horizontal shift means you can shift 34% of the image width from side to side? So if you have a 100" wide screen, the projector could be mounted off center by as much as 34 inches? (that doesn't seem right?)

The manual zoom lens has a range of 1.4:1 ∼ 2.8:1. Multiply this number by the screen width to determine how far from the screen the projector can be mounted. If your screen is 100" WIDE, you could mount the RS1 between 140 inches and 280 inches from the screen. Correct?

In the demo I attended Rob, the JVC reps talked about the lens shift. One of the points they made was that the vertical and horizontal shifting are not totally independent. In other words if you had to use the entire 80% vertical shift you would not be able to shift the lens the full 34% horizontally. So I am assuming that if you had to shift the lens 10% vertically, it would reduces the horizontal shift you have available by roughly the same amount. Does this make sense?
So I don't believe that someone could plan to mount this unit in a spot that would require the full 80% vertical and 34% horizontal shift at the same time.

keithsimp · 03-03-2007, 09:38 AM

Mike is faster at typing than me. But basically we are saying the same thing.

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