My Ruby test at home - Page 16  

The Lumagen scaler has a 11 point gamma/grey scale adjustment. You could individually go into the 90 & or 100ire and tame it down a little. I wonder if that would help.

Greg,

Yeah, I guess you summed it up pretty well - I should have re-read the review. But I guess we've been batting around the term "compression" and I think I would call it "blown whites". I do understand that its squeezing some detail that is in the signal closer together, so in theory anyway, it should look better than blown out whites, but that is the effect I see. You are right - there is a choice between modes, but the potential is clearly there to mitigate the issue in the "auto" mode. Its a killer PJ despite my bringing this up.

- Chris

Intreresting. How would you rate the ruby vs HS60 then?

The HS51 does have "brightness compression". This was pointed out in Bill Cushman's excellent WSR review over a year ago. I never became the same kind of issue as with the Ruby. I don't recall any HS51 owner doing A/B and obsessing over it.

I looked at the HS51 for the Star Wars "brightness compression' scene gregr referenced in his Ruby article. There was clearly some loss of details in the Rocket nozzle using IRIS-AUTO, during an A/B. The positive benefits are so obvious that an inocucous slight less loss of bright level detail is trivial price to pay.

For me the "brightness compression" issue is similar to DLP's low level dithering issue. Technically a real issue, in the real world movie watching, much ado about nothing!

[quote=ChrisWiggles]yeah noah:

Quote:
Yes, one reads that, however for digital projection it is largely B.S.

It is true for film projection where light is projected through film and onto a screen. The film provides the color for the image. An accurate and complete spectral range in the light source is essential for the colors to be full spectrum and accurate in the image on the screen.

Digital projection creates a color response in the human eye/brain by an entirely different mechanism. Digital projection (as with CRT TVs and other types of video displays) only diplays three colors directly on the screen: Red, Green, and Blue.
All the those other colors you see are your brain's interpretation of different combinations of just those three colors. You could just as well use three monochromatic lasers, one each for R,G,B to do the same thing. You can't get any further away from full spectrum light than that!



That's not correct at all.
QUOTE]

O.K, Chris. What part of the above do you think is in error?

Glenn

Sorry, I don't, but I think that William P. answered this earlier in the thread.

Glenn

The standard primaries are defined as single points in color space. They are not defined as single wavelenths of light.

Our whole video system is patterned after the function of the human eye/brain. The eye has three types of color sensors (three types of cones). One type of cone is most sensitive to Red light, one to Green, and the last to Blue light.

When light falls upon the cones, each cone is stimulated in particular way. This stimulation pattern is interpreted by the brain as color.

The points in CIE color space represent specific stimulation patterns (which is just another way of saying that they represent specific colors).

Any particular stimulation pattern can be created by a variety of different light wavelenth combinations. That is why three lasers (R,G, and B) can be used to create the same stimulation patterns in the eye as xenon light that has been filtered into R,G, and B. The lasers in combination will be comprised of just three wavelengths of light. The filtered xenon light in combination might be comprised of 400 wavelengths of light. Yet, they can both ellicit the same stimulation patterns in the eye, though through very different spectral signatures. When this happens, you can't see any color difference.

The CIE has defined the exact points in color space for the R,G,B primaries. If a display has accurate primaries, it will make accurate color provided that all the other ingredients (color decoding, gamma tables, etc) are executed properly.

Glenn

Taking the moving white bar at AVIA as an example, Ruby makes it be less visible while HS51 and HS60 don't show the same situation. I didn't compare all the scenes mentioned by Greg in WSR. I'm not aware HS51 and HS60 has the same degree of brightness compression.

Sorry I didn't write down the exact coordinates of three primary colors. But comparing both CIE charts, Wide colorspace shifts the green to the right hand side a little bit while Normal colorspace shows the green on the exact point of NTSC standard. Wide colorspace has similar red as Normal colorspace which is located slight below the NTSC standard. For the blue, Wide colorspace shifts it to just above the 0.1-y gridline while Normal colorspace is just below the 0.1-y gridline.

Wouldn't this be the broadcast industry? REC-709, etc. Not a CIE function. :)

Yes, thanks for the correction.

Glenn

CKL,

I did not find this. However, I am glad that someone put this up, because I am a little confused about the "Wide" mode compared to the "Normal" mode. I expected the Wide mode representing a HDTV colorspace and normal mode respresenting something near NTSC etc.
The manual says something cryptic like "natural colors" (wide) vs. "Hi-Vision" colors (normal).

When I measured both modes I did not find any (!) difference in the x,y coordinates of the primaries and secondaries (slight variations begin at the 3rd decimal place or so).

VW-100 was fed via HDMI. Maybe this feature does only affect other inputs and/or signals?

In order to correct the oversaturated colors I had to fiddle with the RCP feature and with the global saturation controls. I can post some charts of the different modes and the results after RCP+saturation, if needed.

Thomas

My measurement is carried out via HDMI input. What tools are you using to measure the primary colors?

To correct the oversaturated colors, the item of Color adjustment can't solve the problem?

Thomas,

I measured no CIE x,y differences for the primary colors (to 3 digits), and only a difference in the yellow complementary color, when switching from Wide to Normal. The major difference in switching from Wide to Normal was a reduction in the brightness of the primaries, but not the x,y values. In addition, I was only able to make very small changes to the x,y values of the primaries using the RCP function. I was able to make larger changes to the complementary colors. I duplicated these results with 3 different measuring devices.

Is that also what you measured?

CKL - The primaries lie well outside the Rec 709 and Rec 601 standards.

Greg,

This is exactly what I experienced.

Yup, this is true especially for Green. However, in conjunction with the saturation control I was able to correct all primaries and secondaries.

All measurements were taken with a Gretag Eye-One.

Here´s comparison factory-vs.-my-trials-charts. factory default: "Cinema" mode, colortemperature "mid".

Thomas

Thomas - thanks for posting those charts. Great job on this - it looks nearly perfect.

Can you please post more specific details on how you used which controls to achieve this?

Also - I have a EyeOne and never had much luck getting it to give good CIE measurements with my Sharp 10K. So hearing you were able to achieve this with the EyeOne is very encouraging. Perhaps the difference is that the Ruby is much brighter than the 10K which may make the readings from the EyeOne more reliable under that circumstance?

lovingdvd,

unfortunately I am a bit in a kind of hurry, because of some christmas preparations for my son, family things etc., so I will not be able to look into the specific numbers in the projector today.

First of all I set the whitepoint to D65 by changing the gain values for R,G,B. In order to move the green (and also red) primary significantly I had to reduce the overall saturation ("Color"). This shifted all primaries and secondaries into the right direction - as a beginning.
Next, I chose "Green" (RCP: Color select), I left position and range unchanged in order to make sure (respectively: I hoped...) that the whole spectrum "around " the selected color is changed.
The "RCP Color" control sort of affects the distance of the selected primary from the whitepoint. In the case of green I ended up at a value of -46 or so.
The "RCP hue" control sort of rotates the selected primary around the whitepoint, so one can shift e.g. green towards yellow or towards cyan as desired.
Please take notice that I say "sort of" in both cases, because these controls do not act perfectly the way I would have expected them to do.
Having changed all the primaries I did the same thing with the secondaries.

In the end it worked somehow, although one loses a lot of luminance by correcting the Gamut. For example I measured around 10 ftl. for the green primary at its factory setting (wide mode). After my changes I ended up at around 8,5 ftl. for green.

On the other hand one can compensate this, because I found quite a lot of headroom in the gain-controls until green and blue limited it (almost simultaneous).

Factory settings (cinema, mid, auto-iris); 78,74 inch wide screen; 1,0 gain; 15 foot throw distance resulted in 14,9 ftl. at 100 IRE full white.

Measurement after RCP color correction, D65 whitepoint, RGB-level correction resulted in 20,2 ftl. at 100 IRE full white.

All this is just some very rough and very early trials with the Ruby without looking into the factory-mode or so. I wished that someone will get a documentation about the factory-mode someday...

Thomas

Thanks for the info Thomas. Unfortunately, I think some of those controls are gone for 1080p48 input into the DVI as it seems to be treated as a computer signal.

I read the review, but didn't recall if there was a recommendation for which mode to use in there. After getting the Ruby one of the first things I did was set it to Normal, but it sounds like Wide might be the better choice in general. Do I have that right?

--Darin

darinp2,

you are right: saturation control is gone when feeding the Ruby with DVI. However, wouldn´it be possible to reduce saturation at the external scaler or HTPC and input the already less saturated signal into the Ruby? RCP is still available when using DVI.

Thomas

Hi Darin,

Greetings and thanks for sharing your success feeding 1080p 48Hz signal to a RUBY using DVI. I am thinking of setting up a simple PC-DVI-RUBY system for movie playback, and would be most grateful if you could help me out with some outstanding questions.

1. I assume you have also run the RUBY at 50 and 60 Hz refresh rate and the RUBY had no problem accepting all three. Were you able to get Sony to confirm this?

2. Were you able to detect any sign of judder when using different refresh rates, perhaps using the Judder Test software written by another forum member Arca? This is to confirm that no frame rate conversion is involved.

3. Did you use Powerstrip for refresh rate adjustment, and if so would you be kind to share the timing used? Was it just a simple matter of changing pixel clock, or did you have to fiddle with the porches as well?

4. Was the OSD able to display precise horizontal and vertical frequencies of the input signal?

5. Any means for black level calibration, or video level selection between 16-235/0-255 to match with the VMR/Overlay output of the graphics card?

Thanks agains and best regards.

hi, am new here, and thanks for the useful review on the sony ruby. can someone kindly advice if this projector is suitable for my diagonal 160" screen??

No, it's not by a wide margin. You can find a lot of Ruby brightness discussion by searching the forum.

am using ruby on a 139 inch wide hipower..just fine

I'm really impressed. Maybe I have a night vision deficiency, without having known it up to now :D

it is a 2.8 gain screen

Right 2.8, maybe 3.0, around its max gain. However its important to note for anyone unfamiliar with the HP, its only a 2.8-3.0 gain screen is you have almost zero angle formed between the lens to screen and screen to eye (which basically means that the pj needs to be shelf mounted right above your head).

Thanks. I'm aware of that ;)

I use a High Power too, but at 165" I have no chance with the Ruby, unfortunately. But maybe I should not make such statements before having been at the ophthalmologist ;)

no, i dont think ruby would work at that size screen, but who knows.... a little lasik-ectomy might just work

There must be at least a thousand posts on the Ruby and screens the past couple months. I think I've posted a hundred of them myself. I have a 133" diagonal High Power. When I first got ruby the picture was too bright for me and I suspect it would have been perfect on a 160" diagonal screen. After about 100 hours on the bulb I can already see a noticeable drop in brightness. Now I would say that its brightness is just about ideal on my screen and would guess it would be on the dim side of OK on a 160" screen.

However, by all accounts I can expect significantly more drop in light output as the bulb continues to age. Based on GregR's and other's measurements, I've lost over 10% output so far and have another 40% loss to go, most of it in the next couple hundred hours. By that time my screen brightness will be around 10 to 12 fL which for me on the low side of good and on a 160" screen it would be around 7 to 9 fL which is lower than most on this forum would like. That level would be considered a very acceptable level by people used to CRT projectors. Keep in mind that this assumes getting 2.8 gain from the High Power. People using ceiling mounted projectors with the High Power won't get that nor will viewers off to the side.

Theoretically speaking... ;)

I predict much worse actual results.