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JVC RS40/X3 Calibration Thread

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#1 ·
This thread is intended to provide discussion of the calibration of JVC DLA-RS40 and X3 projectors. While these projectors lack a full Color Management System (CMS) capability, they can benefit from proper calibration for correct grey scale, gamma and color accuracy (within the constraints of not having a full CMS).


The DLA-RS40 and the DLA-X3 are essentially identical projectors except for a minor cosmetic difference. All references to the RS40 below equally apply to the X3.

This first post of the thread will be updated and expanded over time.


The RS40 (also includes RS50 & RS60) Owner's Manual (multi-language version) is available for download HERE (US version)


Firmware updates for the RS40/X3 are available for download HERE (US JVC)


Main RS40/X3 Owner's Thread is HERE


The AVS Thread for the calibration of the previous generation RS20/HD750 projectors is HERE


Most of the adjustments necessary to calibrate the RS40 can be accessed via the user menus. However, there are some additional adjustments and information that is only available via the projector's service menu. To access the service menu:

Press up, down, right, left, enter (press these buttons in this sequence and do it fairly fast). You may need to try several times to get the timing just right to bring up the service menu screen.

CALIBRATION TOOLS


The essential tools you will need for calibration of your JVC projector are a PC (a laptop is the most convenient), a optical sensor (colorimeter), a Blu-ray compatible disc with a set of HD test patterns, and colorimeter software for your PC that will record and report the measurements. Assuming you already have the PC and a blu-ray player, the only things above that you will actually need to purchase is the colorimeter sensor and a blank recordable DVD (total cost about $150 US).
  • Colorimeter Sensor: Probably the most popular low cost, quality colorimeter sensor is the now discontinued Eye-One Display LT (often just listed at the i1LT) made by X-Rite. HERE is the manufacturer's link and HERE is the link for it on Amazon. The substantially more expensive Eye-One Basic Pro is a popular sensor (actually a Spectroradiometer instead of a Colorimeter) for professional calibrators. Another colorimeter of intertest to the hobbyist is the Chroma 5 (priced between the two Eye-one models described above). Finally X-Rite released in mid-2011 a new model colorimter called the i1 Display 3 (this sensor may also be called the i1 Display, i1 Display Pro or may in some cases be referred to as the i1 Display 3 Pro or i1 Display Pro III by some dealers for a calibrated version - so check the details before you order). This new low cost model is much more accurate than the i1 Display 2 series (e.g., Display 2 Pro and Display LT) that it replaces and is said to maintain accuracy better over time than the Display 2 or Chroma 5 series. Important - see the note below before purchasing this colorimeter.
  • Colorimeter Software: A widely used free colorimeter software program is called HCFR Colorimeter. The new (2012) web site for an updated version of the HCFR software is HERE and the AVS Forum discussion thread is HERE . A number of companies sell commercial calibration software. CalMAN and ChromaPure are among the more popular alternatives. HERE is an article comparing HCFR (original version), ChromaPure and Calman software.
  • Software Calibration Aid: An AVS Forum member (stereomandan) has prepared a very useful Excel spreadsheet that can be used as a companion to the colorimeter software. HERE is the AVS thread where you can download the Excel spreadsheet file and the instructions for using it.
  • Blu-ray Compatible Calibration Disc: The AVS HD Calibration Disc (ISO file that can be burned on a DVD +/- R) is described and can be downloaded HERE . Once downloaded you can use a commercial program such as Nero or a freeware program such as IMGBURN , to create a playable disc by burning this ISO image file onto a blank DVD (-R, +R or RW as long as it is a disc type that is compatible with your Blu-ray player).
  • Calibration for Dummies: General overview of display grey scale and color calibration is HERE
  • More Tutorial Information on Calibration of Projectors: HERE is the link to the AVS calibration thread for some earlier Epson projectors that provides a lot of basic information in Post 1 that generally applies to the calibration of projectors.

Note on X-Rite i1 Display Pro III colorimeter and compatable software: Tom Huffman, creator of the ChromaPure software, posted the following information in another thread here on AVS just as the i1 Display Pro III was being released:
"I just had a lengthy discussion with X-Rite, and here's what I learned. There are actually 3 versions of this meter--ColorMunki, i1 Display Pro III retail, and an i1 Display Pro III OEM.
  • The ColorMunki and Display Pro retail are for the retail market only and are designed to work with the included X-Rite software for monitor profiling.
  • The retail versions will NOT function in ChromaPure or any other vendor's software other than X-Rite. Only the OEM version will work because the code in ChromaPure includes a password for enabling it.
  • The retail and OEM versions of the i1 Display Pro are otherwise identical.
  • If you want to use this meter with ChromaPure, then you have to obtain the meter from ChromaPure directly, one of my partners (e.g. AVS), or another OEM vendor. Versions of this meter obtained in the retail market will not work."

The OEM version of the i1 Display 3 or the i1 Display 3 Pro (calibrated) is now available as a package with the ChromaPure software.







____________________________________________________________ ______
 
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#2 ·
This post is intended to provide some tips that may assist other users attempting to calibrate their RS40 projector. If you have additional tips that you would like to share, please send me a PM.

1. HDMI Input Mode - The RS40's menu for Input Signal includes 3 alternative settings for the HDMI input mode. Any of these 3 options can be used as long as the reference black level (i.e., video level 16) and the reference white level (i.e., video level 235) are calibrated for the HDMI input mode you have selected. Some calibrators prefer to set the projector to display some of the video levels just above reference white to accommodate those occasional video sources that (incorrectly) output such whiter-than-white video levels.
  • The "Standard" setting for HDMI input mode will not allow for video signal levels of blacker-than-black (i.e., levels 0-15) nor whiter-than-white (i.e., levels 236-255) to be displayed.
  • The "Enhanced" setting allows all video levels (i.e, 0-255) to be processed/displayed and this setting makes it somewhat easier to correctly set the reference black level and the reference white level when using calibration test patterns such as found on the AVS HD Calibration disc (see link in Post #1 above). This mode allows for calibration to allow the display of whiter-than-white content if desired.
    Note: Iif you are setting up a custom calibration intended for displaying graphics or games from a PC then the "Enhanced" mode is appropriate since the standard levels for computer displays covers the full 0 to 255 range with 0 being reference black and 255 being reference white.
  • The third HDMI mode is called "Super White" and in this mode video levels from 16-255 are processed/displayed. Thus this mode can also be used if the calibrator desires to allow the display of whiter-than-white content.

2. Setting Reference Black Level - Normally the brightness control is adjusted to set the reference black level when displaying an appropriate test pattern (the AVS HD Calibration Disc, see link above, has an excellent test pattern for this). Video levels are defined such that level 16 is reference black and it should appear on the display just as dark as all lower video levels (0 thru 15), while video level 17 should be just very slightly lighter (very dark grey) than level 16. Before you attempt to calibrate the black level go into the RS40's installation menu and set the "Black Level" adjustment to 0 (zero). Next while displaying the test pattern use the RS40's brightness control to set the reference black level. You may find that one click of the brightness control provide too coarse of an adjustment going from the reference black level being just a little too low at one setting, to a being just a little too high with the brightness set just one unit higher. If this is your case then set the set the brightness control to the lower of the two values (darker setting), then go back to the Installation menu and increase the setting for the "Black Level" adjustment. You will then need to exit the black level adjustment menu in order to see the calibration pattern displayed from your calibration disc. You may need to try adjusting the "Black Level" control in the RS40's Installation Menu a few times to find the setting that gets the displayed black level to match video level 16 (reference black) from the calibration disc.

3. Selecting Color Space - The color accuracy of your RS40 projector varies by the combination of the settings you select for "Color Space" and "Picture Mode." The RS40's 'Color Space" setting that provides the most accurate colors is "Standard", which is intended to provide color points close to the HD Video Standard, Rec. 709. JVC USA recommends using "Standard" Color Space in combination with "Natural" Picture Mode for viewing HD 2D sources. Some viewers might instead prefer use of "Film" or "Cinema" Picture Mode.

4. Grey Scale Calibration - When doing a D65 calibration (i.e., using a sensor {e.g, colorimeter} and calibration software on a connected PC) first go to the RS40's "Color Temperature" menu and set the Color Temperature to 6500K. Then create a "Custom" color temperature profile using the RGB gain and offset adjustments. First with the gain controls set to zero run a set of RGB level measurements, using your sensor and calibration software, and see which color level is the lowest. Going to the projector's gain control for the color measured to have the lowest output, leave that gain control set to zero and then decrease the settings of the other two colors to bring them down to match that level. With luck in a few attempts the RGB levels will measure to track well from perhaps 30% grey level upward. The RGB offset controls have the most effect for the lower end of the grey scale (e.g., 0 to 30%) and you can adjust these after you get the colors levels matched for the mid-to-high levels. It is recommended by some calibrators here on AVS to not use positive Offset values (i.e., use only offset values of 0 or less).

5. Measuring Projector Lumens Output - If you want to measure the projector's lumen output the best measurement tool is a lux light meter. With such a lux meter the measurement is performed by placing the meter's light sensor directly in front of the projection screen with the sensor aimed back toward the projector. The lux reading can easily be converted in lumens (more on that below) and there are two measurement approaches commonly used. A projector's peak lumens output is typically based on a single measurement from directly in front of the center of the screen. A projector's ANSI lumens is based on the average of 9 individual measurements made by dividing the screen into a 3 x 3 grid then making a measurement at the center of each of the 9 rectangles of the grid. I have attached a zip file that contains an small Excel spreadsheet that makes it easy to calculate the projector's lumens (either peak lumens using the center of screen measurement location or the ANSI lumens based on 9 meaurement points). Many hobbyist calibrators are using the AEMC CA813 light meter (price is under $180 from most sources). I tested a very low cost (i.e., less than $40) digital lux meter ( Mastech LX1330B ) that, at least for the sample I tested, gave similar results.

 

Lux to Lumens Calc - v2g.zip 3.9033203125k . file
 

Attachments

#3 ·
MY PRE-CALIBRATION RESULTS


I have seen a couple of published CIE Diagrams for the RS40/X3 that shows the color space for this projector. The cine4home preview (translated version is HERE ) of the pre-production X3 and X7 included these. These diagrams showed for the Standard color space setting on the projector, which is supposed to be closest to Rec. 709 standard color space for HDTV, the green color point was the most off. I have performed some calibration measurements on my RS40 and have found that the CIA diagram looked similar to what I had seen published when the projector is operated in Cinema mode and with the color space set to Standard. However, the color points are actually somewhat different, and perhaps overall closer to the rec. 709 HDTV standard, when the projector is operated in "Film" mode with the color space set to Standard. I have also measured the projector with the Picture Mode set to "Natural" and with color space set to Standard. See the three diagrams below.


CIE Diagram - Cinema Picture Mode - 6500K - Color Space Standard - Gamma Normal



CIE Diagram - Film Picture Mode - 6500K - Standard Color Space - Gamma Normal


CIE Diagram - Natural Picture Mode - 6500K - Standard Color Space - Gamma Normal



____________________________________________________________ _____________________________

HIGH LIGHT OUTPUT MODE


JVC has rated the RS40 projector for a maximum light output of 1300 lumens. This level of lumens cannot be obtained in any mode that provides more-or-less accurate grey scale and colors. I performed a set of measurements with settings that provide a lumens output that is close to the claimed 1300 value (when using a new lamp). These settings were made with the projector's setting for color temperature set to "High Bright". The other settings I used were High Lamp, Standard Color Space, Natural Picture Mode, Iris fully open and Normal Gamma. These measurements were performed with approx. 65 hours of the lamp.

CIE Diagram - High Bright mode


RGB PLOT - High Bright mode


COLOR TEMP - High Bright mode
 
#4 ·
Ron, thanks for starting this thread. I currently have an older HD350, but I expect at some point I will upgrade to either an X3 or X7. Your results with the X3 might influence my decision. I am also debating changing my VideoEQ Pro plus Edge for the new Lumagen so depending on the results with the X3 particularly then I may feel that this is not necessary for my requirements. I'm not so critical of colour issues once they get within a certain level of accuracy. I think this level may be achievable by the X3, but whatever the 'best' results are for it I can simulate with my VideoEQ, which is why I'm keen to see just how well it can be adjusted using the user controls and the service menu CMS adjustments too.


A couple of (hopefully) constructive points:


With the HDxxx series it was generally considered not recommended to raise the offsets above 0 as this can raise the black level. It might be worth trying with the same proportions, but so that your blue offset is at 0 and the red and green the same number difference as was usually recommended by those on the HDxxx calibration threads.


Also the use of the enhanced HDMI mode just to allow 'better adjustment' of the brightness control should be tempered with the possiblity that using the 'incorrect' HDMI mode may introduce banding. It is a mistake to think that it will gain any extra brightness for example by using this mode once the contrast and brightness are adjusted accordingly. Using the AVS HD709 disc I find it quite easy to adjust the brightness correctly without needing to see BTB.
 
#7 ·

Quote:
Originally Posted by lovingdvd /forum/post/19848014


Ron - if the RS40 is anything like the RS20 in terms of calibration, I highly recommend not using any positive numbers for your offsets. Doing so with the RS20 raises the black level considerably, even just a single click on one color (i.e. +1 for any setting).

Interesting. I wasn't aware of this. I just checked the settings on my HD750 and found that I have:


RG -6

GG -18

BG -68

OR +1

OG -2

OB +1


Just going into positive by +1 raises the black levels considerably? What do you think my settings are doing? It's currently away at JVC at the moment so the settings will probably returned all wiped (if they haven't replaced it - please God
- with an X7) so I'll take a look at it.
 
#8 ·

Quote:
Originally Posted by Canary_Jules /forum/post/19849066


Interesting. I wasn't aware of this. I just checked the settings on my HD750 and found that I have:


RG -6

GG -18

BG -68

OR +1

OG -2

OB +1


Just going into positive by +1 raises the black levels considerably? What do you think my settings are doing? It's currently away at JVC at the moment so the settings will probably returned all wiped (if they haven't replaced it - please God
- with an X7) so I'll take a look at it.

What I and others have found is that any positive value in any of the offsets raises the black floor above what you would normally have set as the ideal value for the brightness control. IOW absolute black is now higher than what it should be. IMO its considerable because anything above what the blackest black can be is considerable to me.
 
#9 ·
Hi Ron,


Great to start this threat because I'm also interested to know more about X3 calibration. I own a Lumagen XS and I need some good starting point for the Radiance.


It would also make sense that we discuss here "best practice" for an external VP with X3. I can share my approach to calibrate the X3:


I just use the 3 User-Preset for, High/Low Lamp and 3D settings:


1.) Calibrate 100IRE with the "Gains" form the X3.

2.) Wide1 as Colorpreset to not limit my Lumagen CMS by the X3

3.) Calibrate Gamma/Grayscale with Lumagen to 2.2

4.) Use Lumagen CMS to adjust Colors to Rec.709


Done!!


The results are good, but the linearity especially form 75IRE to 100IRE is not so good. Maybe somebody else with an external VP can recommend me an other "base" or "starting point" of the X3?
 
#10 ·

Quote:
Originally Posted by lovingdvd /forum/post/19848014


Ron - if the RS40 is anything like the RS20 in terms of calibration, I highly recommend not using any positive numbers for your offsets. Doing so with the RS20 raises the black level considerably, even just a single click on one color (i.e. +1 for any setting).

Yes, but can't you readjust the "brightness" control down the number of clicks it needs to regain proper black level? I agree that 6500 black is obtainable using the proper combination of negative offsets, but this has just as much potential to lower or crush black too much (having to raise the overall black level back up to the proper setting-essentially just the opposite of what I mentioned above)
 
#11 ·
Kris Deering over in the RS40 owner's tread has investigated the service menu adjustments for CMS. These are not a full CMS set of adjustments, and are not described in my available documentation, but they do allow you to make some minor adjustments to the color points. Below is a copy of his post:
So I played with the mini CMS in the service menu. There are two adjustments that affect red and yellow. You can get the color points to be pretty close to 709 this way, but you can't get luminance perfect. The other two affect green, blue, cyan and magenta. The one colored green adjusts green and cyan the most, and you will have to find the best compromise of the two. I was able to get green pretty close to the right target point, but cyan is a bit oversaturated. The other adjustments affects magenta the most, with none of them doing a whole lot for blue. Unfortunately none of the adjustments does anything for luminance so again you'll have to find the best trade-off between all of them. Overall I was able to get most of the points closer to the spec with about the same level of delta for luminance, so only slightly better than before. If you want a completely accurate calibration, you're going to need an outboard processor.
Quote:
Originally Posted by Kelvin1965S /forum/post/19846612


Ron, thanks for starting this thread. I currently have an older HD350, but I expect at some point I will upgrade to either an X3 or X7. Your results with the X3 might influence my decision. I am also debating changing my VideoEQ Pro plus Edge for the new Lumagen so depending on the results with the X3 particularly then I may feel that this is not necessary for my requirements. I'm not so critical of colour issues once they get within a certain level of accuracy. I think this level may be achievable by the X3, but whatever the 'best' results are for it I can simulate with my VideoEQ, which is why I'm keen to see just how well it can be adjusted using the user controls and the service menu CMS adjustments too.


A couple of (hopefully) constructive points:


With the HDxxx series it was generally considered not recommended to raise the offsets above 0 as this can raise the black level. It might be worth trying with the same proportions, but so that your blue offset is at 0 and the red and green the same number difference as was usually recommended by those on the HDxxx calibration threads.


Also the use of the enhanced HDMI mode just to allow 'better adjustment' of the brightness control should be tempered with the possiblity that using the 'incorrect' HDMI mode may introduce banding. It is a mistake to think that it will gain any extra brightness for example by using this mode once the contrast and brightness are adjusted accordingly. Using the AVS HD709 disc I find it quite easy to adjust the brightness correctly without needing to see BTB.

Thinking about why using positive offsets might raise the absolute black level, since we normally only measure the effect of the gain and offset in 10% increments it is possible that by using the offset adjustment to pull up the curve to make it flat at 10% we might actually be boosting up the values even further at values below 10% (which are typically not actually measured). This is certainly worth investigating with the RS40 to see if the offsets do raise black level as several have reported was the case with older JVC DILA projectors. As for using the enhanced HDMI setting, so far I have seen no evidence that doing the calibration in this mode results in banding. Banding was a well reported issue in general with the previously generation of JVC projectors that JVC claims has been substantially improved with the new models. Banding in displays frequently is caused by not have enough bit-depth for the display and banding occurs when changes in value to the lowest order one or two bits are causing a large enough change in the displayed luminance level to be clearly visible. It's my undertanding that this new generation of projectors increased the bit depth for the display.


Quote:
Originally Posted by nightfly85 /forum/post/19848896


Can you post the CIE charts from the result of your preliminary calibration - the noted two both state "pre-calibration".

My plan is to have Post #1 be a post for FAQs on RS40/X3 calibration and info on the "out of the box" performance (i.e., pre-calibration results). Once I do a more proper calibration of my own RS40, including the mini-CMS adjustments in the service menu, I plan to post those results in Post #2 or #3 (both now reserved).
 
#12 ·
You want to avoid reducing all 3 gains, as this will reduce contrast from the top end. You want to avoid increasing any offsets, as this will reduce contrast from the bottom end as well as compromising black level.


Use 80% and 30% IRE fields to set greyscale. If you find that 100 IRE is out, use the gamma controls to correct it.


So far I have never needed to reduce all 3 gains on any JVC projector, or raise any offsets. If you are getting with 2-3 dE (1976) for greyscale, and cannot do any better without resorting to one of these "no-nos" don't..you won't notice such a small deviation anyway.
 
#13 ·
Great info here. I will have to take a look at my cuts and gains again when I get back. I don't think I have all 3 gains reduced currently but I may have a offset raised. I do notice that the black floor is slightly higher than the "hide" mode and have tried several things to try to alleviate this so I will look into this more when I get home.


As for the mini CMS, while it does seem to improve things based on measurements I wasn't as impressed with viewing compared to just adjusting color using red luminance. I looked at some program material yesterday and with the adjustments made in the CMS I started seeing some yellow casting in fleshtones that isn't there with my other settings. My wife even noticed it immediately and commented on it. So tread with care!
 
#14 ·

Quote:
Originally Posted by Ron Jones /forum/post/19845972

Note 2: I have the HDMI input set to "Enhanced" mode (see submenu 2-1 description in the owner's manual) so that it passes thru the full 0 to 255 levels as this makes it a lot easier to correctly calibrate for reference black = 16 and reference white = 235. However, I have let some of the super-white (levels above 235) be displayed to avoid white crush for the cases where the source material does contain video at these elevated white levels.


I also found all of the pre-stored Gamma Settings were poor with low gamma at both ends of the curve and high Gamma in the middle (e.g., 1.7 at the ends and 2.3 in the middle) and while I spent some time working on a custom gamma setting I'm not fully satisfied with it yet and will spend the extra time necessary to get it better when I do a more full-up calibration after I get perhaps 100 hours on the bulb.

While I realize that showing above 235 is correct, with the JVCs I use the standard setting and not enhanced because of my feeling that since JVC defaults to that and a Brightness setting of 0 is what goes with that, using it is less likely to have other things messed up in the projector, like gamma. I wonder if you would have the same gamma problems if you used standard and a Brightness setting of 0. Since 3D doesn't seem to give us any more than 2 gamma choices I think it is possible that using standard and Brightness at 0 will be a better compromise in those modes than using enhanced with Brightness at -6 or -7, although I haven't measured gamma in them.


As far as how easy it is to set the Brightness in standard without being able to see below black, I don't find it that difficult. I use an AVS Rec.709 test disc with flashing bars for different low levels and then verify that I have the Brightness setting where I want it by putting up a completely black image and seeing if the image changes between Hide and not. If it doesn't change then I know I don't have the Brightness setting higher than I want and if bars 17 and above show up I know I don't have it lower than I want. There can be some compromise here where I may give up the bar for 17 though.


--Darin
 
#15 ·

Quote:
Originally Posted by darinp2 /forum/post/19851504


While I realize that showing above 235 is correct, with the JVCs I use the standard setting and not enhanced because of my feeling that since JVC defaults to that and a Brightness setting of 0 is what goes with that, using it is less likely to have other things messed up in the projector, like gamma. I wonder if you would have the same gamma problems if you used standard and a Brightness setting of 0. Since 3D doesn't seem to give us any more than 2 gamma choices I think it is possible that using standard and Brightness at 0 will be a better compromise in those modes than using enhanced with Brightness at -6 or -7, although I haven't measured gamma in them.


As far as how easy it is to set the Brightness in standard without being able to see below black, I don't find it that difficult. I use an AVS Rec.709 test disc with flashing bars for different low levels and then verify that I have the Brightness setting where I want it by putting up a completely black image and seeing if the image changes between Hide and not. If it doesn't change then I know I don't have the Brightness setting higher than I want and if bars 17 and above show up I know I don't have it lower than I want. There can be some compromise here where I may give up the bar for 17 though.


--Darin

I agree that reference black can be set in HDMI normal mode, its just easier to do it in enhanced mode. With my previous projectors (but no JVCs) there were no negatives with passing the full 0 to 255 range then calibrating for reference black=16. I guess we are currently at the point that there is speculation that setting the HDMI mode to enhanced then calibrating the black and white level may not yield as good of results as using the HDMI normal mode. However, this speculation seems to be based on previous JVC models and I haven't seen any actual test results for the new generation of JVC projectors that this is still the case. Are you using HDMI normal mode, which passes neither levels below 16 nor levels above 235, or the HDMI "super white" mode (which passes nothing below 16 but does pass levels above 235). I have not tested to see if the gamma curve is different by calibrating with the HDMI mode set to normal or super white as compared to enhanced. I guess that's another thing that needs to be tested. As for 3D mode, I have not yet attempted to do any calibration for it.
 
#16 ·

Quote:
Originally Posted by darinp2 /forum/post/19851504


While I realize that showing above 235 is correct, with the JVCs I use the standard setting and not enhanced because of my feeling that since JVC defaults to that and a Brightness setting of 0 is what goes with that, using it is less likely to have other things messed up in the projector, like gamma. I wonder if you would have the same gamma problems if you used standard and a Brightness setting of 0. Since 3D doesn't seem to give us any more than 2 gamma choices I think it is possible that using standard and Brightness at 0 will be a better compromise in those modes than using enhanced with Brightness at -6 or -7, although I haven't measured gamma in them.


As far as how easy it is to set the Brightness in standard without being able to see below black, I don't find it that difficult. I use an AVS Rec.709 test disc with flashing bars for different low levels and then verify that I have the Brightness setting where I want it by putting up a completely black image and seeing if the image changes between Hide and not. If it doesn't change then I know I don't have the Brightness setting higher than I want and if bars 17 and above show up I know I don't have it lower than I want. There can be some compromise here where I may give up the bar for 17 though.


--Darin

Do you think using the Standard Mode (or the Super White mode) with a Brightness setting of +1 or +2 screws up gamma?

(I need the same +1/+2 Brightness setting for Standard Mode as well as the Super White mode)
 
#17 ·

Quote:
Originally Posted by cbaseuser /forum/post/19849799


Yes, but can't you readjust the "brightness" control down the number of clicks it needs to regain proper black level? I agree that 6500 black is obtainable using the proper combination of negative offsets, but this has just as much potential to lower or crush black too much (having to raise the overall black level back up to the proper setting-essentially just the opposite of what I mentioned above)

Yep you probably could. Although you may wind up going in circles. My point is to let people know that they have raised their black floor likely without realizing it. It is subtle and easy to miss.
 
#18 ·
I posted the situation below in the RS40 owner's thread but didn't receive any response. I'm trying now and will in the near future try these different sample settings from our resident experts until I can have mine calibrated by an ISF person I have used before. I would think there are others with the same situation. Could someone take a look at this and comment:
"I've been trying various settings from Page 1 and am puzzled that each set of detail settings does not go with each "master" setting. I percieve a "master" setting to be Film, Cinema, Anime, Natural, Stage, 3D, User1, User2, and User3. For instance, when I change the Color Temp/Custom1 while in Film it also goes across to the other master settings. It seems like it should associate only with Film. I should be able to have a different Color Temp/Custom1 for each "master" setting. This same problem seems to transfer to several other settings also; Custom Gamma for instance. What am I doing wrong here or is my logic screwed up?"
 
#19 ·

Quote:
Originally Posted by JackB /forum/post/19854813


I posted the situation below in the RS40 owner's thread but didn't receive any response. I'm trying now and will in the near future try these different sample settings from our resident experts until I can have mine calibrated by an ISF person I have used before. I would think there are others with the same situation. Could someone take a look at this and comment:
"I've been trying various settings from Page 1 and am puzzled that each set of detail settings does not go with each "master" setting. I percieve a "master" setting to be Film, Cinema, Anime, Natural, Stage, 3D, User1, User2, and User3. For instance, when I change the Color Temp/Custom1 while in Film it also goes across to the other master settings. It seems like it should associate only with Film. I should be able to have a different Color Temp/Custom1 for each "master" setting. This same problem seems to transfer to several other settings also; Custom Gamma for instance. What am I doing wrong here or is my logic screwed up?"

I haven't checked it yet on my RS40, but from your observatons, it appears that the custom 1, custom 2, etc. settings are each just single memory locations where you can save your own settings and these are independent of which "master" mode (i.e., film, cinema, etc.) you are using. For each "master" mode you can associate one of the prestored color temp or gamma settings or one of your custom settings. I guess what you really are wanting is for the projector to offer a far greater number of possible custom settings such that you could define one, two or three different custom settings that uniquely apply to each "master" mode.


For owners of earlier JVC models, is this any different you what was offered with those earlier models?
 
#20 ·

Quote:
Originally Posted by JonStatt /forum/post/19850018


You want to avoid reducing all 3 gains, as this will reduce contrast from the top end. You want to avoid increasing any offsets, as this will reduce contrast from the bottom end as well as compromising black level.


Use 80% and 30% IRE fields to set greyscale. If you find that 100 IRE is out, use the gamma controls to correct it.


So far I have never needed to reduce all 3 gains on any JVC projector, or raise any offsets. If you are getting with 2-3 dE (1976) for greyscale, and cannot do any better without resorting to one of these "no-nos" don't..you won't notice such a small deviation anyway.

Jon, can you elaborate on this topic? I could see out of the box, something was off on this RS50, reds were low, green was off, etc.


I did a greyscale reading on 30 and 80, and adjusted the offsets and gains until it was pretty even. I did a full measurement and and it's relatively flat from 10-100.


I basically did the same thing that Ron & Kris did with the gains/offset. I went through a few movies with dark scenes and A/B back and forth between the custom color setting and the default 6500k setting. I can't see any difference in the black floor by comparison, I can only see the color shift.


I know the display LT isn't the most accurate meter, but I can easily tell that the color had a remarkable improvement vs the out of the box settings.


Should I have been using separate RGB gamma adjustments instead?


thanks!
 
#21 ·

Quote:
Originally Posted by Ron Jones /forum/post/19856043


I haven't checked it yet on my RS40, but from your observatons, it appears that the custom 1, custom 2, etc. settings are each just single memory locations where you can save your own settings and these are independent of which "master" mode (i.e., film, cinema, etc.) you are using. For each "master" mode you can associate one of the prestored color temp or gamma settings or one of your custom settings. I guess what you really are wanting is for the projector to offer a far greater number of possible custom settings such that you could define one, two or three different custom settings that uniquely apply to each "master" mode.


For owners of earlier JVC models, is this any different you what was offered with those earlier models?

Ron,


Thanks for the input. I think you are right. It came to me sometime last night that it would make sense for the three Custom settings to allow you to save every spec independently while the Masters would have more limited customization. I will play with it later today to find out.
 
#22 ·

Quote:
Originally Posted by zombie10k /forum/post/19856147


Jon, can you elaborate on this topic? I could see out of the box, something was off on this RS50, reds were low, green was off, etc.


I did a greyscale reading on 30 and 80, and adjusted the offsets and gains until it was pretty even. I did a full measurement and and it's relatively flat from 10-100.


I basically did the same thing that Ron & Kris did with the gains/offset. I went through a few movies with dark scenes and A/B back and forth between the custom color setting and the default 6500k setting. I can't see any difference in the black floor by comparison, I can only see the color shift.


I know the display LT isn't the most accurate meter, but I can easily tell that the color had a remarkable improvement vs the out of the box settings.


Should I have been using separate RGB gamma adjustments instead?


thanks!


I had a quick test with the offsets and if I raise green particularly, I see the black floor lifting with just 1 click. This was the same as previous JVCs. Similarly lowering all 3 gains will squash the contrast from the other end.


Typically as a bulb ages, red drops off first. So normally gains are only lowered for green and blue to match the lowered red. Conversely with the offsets, you normally tend to lower red, as at the lower IREs, red is still strong.


With my unit, I found that if I calibrated against 30 and 80 IRE, that 100 IRE seemed to deviate off again. In other words it didn't track linearly. But there is a fix for this, with the gamma. In the gamma controls you can adjust red , green and blue separately at the various IREs. So you can pull in small dEs of error with the greyscale using the individual gamma controls.



Further up in the thread, someone had the following values with their HD750

RG -6

GG -18

BG -68


Now in this case you can see blue was the strongest colour, so has had to drop a long way to match red. However, they have lowered red as well which means we are losing more brightness that we should need to. Admittedly its only 6 clicks so its very slight. I suspect this person ended up doing that otherwise the tracking across all IREs wasn't as good as they wanted. But the solution is to calibrate at say 80 and 30, possibly 90 and 30, and then go fix any small issues with gamma. This way you should be able to avoid lowering red gain , or raising any offsets.
 
#23 ·
Ron Jones,


Do you think you could measure the full saturation scale using HCFR and the AVSHD REC.709 calibration disc and post the resulting chart? There are 30 points total. I am very interested to see how the color saturation tracks at lower saturation levels.


The chart you display labelled "CIE Diagram - Film Mode - 6500K - Color Space Standard - Gamma Normal - PRE-CALIBRATION" is actually quite good for a preset menu option.


If the color saturation tracks decently in the lower saturation range, I may look towards one of these JVC RS40's to replace or add to my current projector.


Dan
 
#24 ·
I've found a bug that affects my RS40 and wanted to see if anyone else sees the same thing. If I cycle power to the projector, the changes I've made to the color temperature settings don't stay. I have Custom 1 selected in the User 1 mode I'm using but the projector doesn't apply them unless I go into the Custom 1 settings and put the cursor on the 6500 selection. Then it applies the settings I've done to it. I don't even have to select 6500, just go to it and highlight it. It did this 3 times yesterday and I will see if it does it again today. If anyone else can try this it would be appreciated.
 
#25 ·
Just to clarify, all the settings I've made to the Custom 1 color temperature (with 6500 as the preset starting point) are there, they just don't apply to the actual image unless I actually go in and highlight 6500 (don't need to select, just go to it in the menu). It retains it the rest of the time but I have to repeat this process each time I power on the PJ.
 
#26 ·
I have tested by RS40 to see what happens to the gamma curve when I calibrate reference black level when the HDMI input mode is set to enhanced vs. with HDMI set to normal. I set the projector to Film mode, normal lamp, 6500K color temp. and gamma set to normal. I used the AVS HD calibration disc to set the brightness adjustment and I eded up setting it to +1 in HDMI Normal mode and to -6 in HDMI Enhanced mode. The two curves were almost identical in their shape with the gamma values for HDMI set to Enhanced just being shifted upward by approx. 0.05. So it looks to me like either setting for HDMI input mode would work as long as you calibrate reference black level and gamma.


Now on the subject of Gamma. What results have others measured for the pre-set gammas. I have checked a few of the presets and they looked rather poor with substantially higher gamme values at the mid-levels and lower values toward both ends. For example, in Film mode and with the gamma set to Normal. the gamma curve starts out at about 2.0 at 10% then climbs to about 2.5 at 40% thru 60% then drops to 2.2 at 90% and 1.8 at 100%. I also tried a couple of the preset numeric curves (e.g., 2.0 and 2.2) they also had this inverted 'U' shape.
 
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