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Discussion Starter #61
This one has always perplexed me a little... different displays presumably have a choice of what LEDs they use, as such, how does a single profile matrix make a colorimeter accurate enough across the range of possibilities?
It gets somewhat complicated, but the issue has to do with tolerances. In other words, a company/manufacturer can calibrate the meter to a particular combination of LEDs, but the accuracy will diminish as you move away from that spec. The upside is that LEDs are actually, in many respects, a more homogeneous lighting technology than what has been used in the past. They still have unit-to-unit variation and manufacturer (of the LEDs and spec) variation, but you don't get as much batch-to-batch variation as you did with things like phosphor (CRT, Plasma, and to an extend CCFL). So, you essentially get a calibration that is more accurate for the technology than using something not dedicated to the technology, but you suffer from wider variances in what manufacturers might put into the display, if that makes sense. Since there are very few manufacturers out there making the necessary blue and "white" LEDs, that tends to constrain the space of what an OEM might actually put into the TV.

Net-net: figure out what the reference display is, and then know that as you drift beyond that manufacturing "group" (e.g., Samsung/Sony/JVC), you might get increased error, but not necessarily enough to invalidate the calibration (LEDs are tough, but doable). To be really sure about things, that's where the $$$ meters come into play, or contracting for a specific calibration for the meter.
 

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I started to calibrate my tv and I have a question about the "Service Menu", not User Menu, for a Samsung LN32a550 tv. If someone (ME...) has gone into the SM and made some changes to the WB & WB-Movie numbers, can they be reset to the factory defaults if you use the "Factory Reset" setting in the SM? I neglected to write them down before changing and hope to get everything back to the default settings before retrying to calibrate my tv again. If not, where can you locate the factory settings for the SM that came with the tv from the manufacturer?

Thanks for any help.
Bob
 

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The only place that might have default settings is the service or training info. I do not recommend a reset in the service manual unless you know what parameters it affects.
 

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That all makes sense Bill. Thanks. Is my understanding correct though, that some of the affordable colorimeters out there are ok unprofiled, even on LED back/edge lights, for grayscale work, and the profiling is only really necessary for CMS work? I'm talknig about the C5 and DTP94.
 

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Discussion Starter #65
I started to calibrate my tv and I have a question about the "Service Menu", not User Menu, for a Samsung LN32a550 tv. If someone (ME...) has gone into the SM and made some changes to the WB & WB-Movie numbers, can they be reset to the factory defaults if you use the "Factory Reset" setting in the SM? I neglected to write them down before changing and hope to get everything back to the default settings before retrying to calibrate my tv again. If not, where can you locate the factory settings for the SM that came with the tv from the manufacturer?

Thanks for any help.
Bob
Agree with Leonard on this one. Most SM "resets" take the display to a common set of values before any device-specific settings are loaded in the production line. In other words, the reset could be worse than simply working yourself out of the current hole.

Always, always, always write down the values you see in the service menu before making any changes. Also, it is usually worth investing the $20 - $30 for a copy of your TV's service manual before you start poking around. It's not a guarantee, but it should sober you up for how little explanation/information is available should you decide to skip rule #1.
 

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Lots of service manuals are available for free if you dig. Virtually all are available for under $20 online. There are suggested sources in the DIY repair stickies and there are vendors in the vendor listings that have manuals.
 

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Thanks Bear5K and lcaillo. You are both, of course, correct. I should have been more prepared instead of just jumping in without much thought! I am looking for a service manual here now but unable to locate one that might have all the settings from the factory shipping setup...but, I'll keep looking.

Thanks to both of you.
Bob
 

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I was hoping that someone might be able to help me. I am a newbie, and have attempted to do a video calibration. I have a Sony KDL52V5100, although it does have controls to do a gray level adjustments, it does not seem to have controls to adjust colors other than the the standard ones found through the remote control (Color & Hue). What is the way to the x,y,Y values for each color? Is this done via the Service Menu? What ever help anyone can give will be appreciated.

Randal
 

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You're stuck with what the manufacturer gives you. I have Sony KDL-52EX700 and I have no controls outside of the color and hue controls to adjust gamut. And if you have the controls to adjust grayscale in the user menu, then the gamut controls would be there as well if the manufacturer were to offer them. I don't think there are many, if any, manufacturers that have calibration controls in the service menu any more.

With just the color and hue controls, you can get it close enough. Here are my chromaticity and luminance charts from my display.





I'm in the process of touching up my displays lately and I'm sure I can get the luminance a bit better than what the above image shows. And my worst DeltaE is 2.9 for green. It is what it is.
 

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Hello,

I have a Samsung LCD TV, model LE32B651 and I need to re-calibrate ADC values in the service menu. My concern is that the TV goes into SM under "dynamic" (or "standard") mode and calibrating in that modes seems a little odd to me. The service menu has this "WB Movie" option wich I can enable and rollback to ADC calibration... should I do that? The service manual has no word about it.

Thank you very much for your answer.
 

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Greetings

Sony ... no
LG ... no
Samsung ... no
Sharp ... no
Panasonic ... no in Custom ... yes if THX mode
JVC ... no
Epson ... no


These apply to the higher end units of the brand, not the budget units which "may" have fewer controls.

Regards
 

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I am so confused over VDO calibration, anyone can help me with it. I appreciate it.

- I use Laptop as VDO source. MKV movies were played and went to HDMI cable to LED display.
As a spyder4elite user (a true beginner) I can basically calibrate PC, Laptop Monitor.

but when I connected Laptop to a TV to do a calibration. there are so many questions

- Backlight, brightness, contrast.
what should i do with backlight? turn it all of to "ZERO"?

- Sharpness
Can a sharpness be calibrated using spyder meter?

- Color
Spydercal didn't tell me a thing how to adjust color

I don't mind buying a Calman 5. I.. I just want to know if Calman 5 can help me with my situation or not.

it seems i am in a deep black pit.
 

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Greetings

What you are finding out is that when you buy a hammer, the hammer does not come with instructions on how to build a house.

Or books on brain surgery do not teach people to be doctors first.

Buying Calman or any other program does not mean you can sit back and let the software do the work. MAgic hands do not sprout from your laptop to calibrate a TV.

To calibrate a display, you need to learn how to do it. Software is a tool, but it won't teach you how to calibrate. Hammer ... instructions to build a house.

To learn to calibrate, you will have to spend a lot of time at DIY web sites readings and teaching yourself how to do this. At some point you might be proficient enough to do a reasonable job.

Much of this comes down to how much you value your time ($$). Is the value of your time worth little? If so, then spend the next year scrounging around for information and you will get to a calibrated TV eventually. IT has been surmised that even when people don't place much value on their time ... they still put something like $3/hr on it. So if we go with something like that ... you are looking at spending at least 100 hours in your learning process. (100x $3 = $300)

If you value your time more and want to get to an end result faster, then you will have to get some professional level training on how to do this. (Starts at $100 ... and up up up after that.) The 7 hours of training videos available from the link on this site is your start to being a competent DIYer. More efficient use of your time and you have more certainty that you did it correctly.

regards
 

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Michael,

I'd be interested in one more opinion on this.

I have a video EQ Pro hooked up to a JVC RS25 (450 hours). Using custom 1 and normal for gamma in the RS25 and I also set contrast and brightness as well.

I also find I need more room in the CMS. I select advance in the video EQ to allow a wider gamut instead of 0-100, it's now 0-200. Brightness usually needs to be around 135 and its perfect.

The question is IF I use over 100, am I boosting to much?

Eric at AV Foundry doesn't recommend it,

In general, it's a bad idea to set either the saturation or brightness above 100. You're going to drive something into over saturation or clipping at some point. If you think about it as a multiplier - sending a full white signal at 255 (8-bit level) with a multiplier of 117% would result in 298, which doesn't fit in 8-bits anymore.

One thing to be very careful of here is that you run plenty of high level content through it before you are done calibrating. I've heard (and seen) some calibrations that are really good by the numbers in CalMAN, and make a nice picture on most content. But then during something like an explosion scene, where the picture level is high, the whole thing clips and gives green/red flashes. Sometimes it's just "sparklies" around the bright edges. What happens is that these bright pixels go beyond the 8 or 10 bit limit and cause problems.

Some implementations will "clamp" the value so that anything >255 is limited to 255. Others could wrap so that 298 results in 42. The first method of clamping fails more gracefully as over-saturation just quietly turns to pure white. It's been a long time since we worked on that part of the Eq, so I can't really remember which it uses.

Also, since the CMS works as a linear function, there is some interdependence between the controls. Meaning you might be able to increase saturation to say 120 if you reduce luminance by 5 or so.

So what does the RS25 at +50 mean? Can I boost it in the RS25 and then further adjust it in the Video EQ?

And why does the RS25 gamma only go to 95? Calman wants 100, my video EQ defaults to 100. Whats the deal.

I'm about to pay someone to come in and do this. Who do you recommend in the Puyallup,WA area?

Thanks,
Dave
 

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Greetings

Get the projector set up as best you can. Then add the video eq into the chain. this minimizes the impact of the EQ device. When you go too far, the eq makes some parts of the image appear solarized ... and discolored.

test patterns that show rgbcmy in the 235-253 range can more easily show that this is happening.

regards
 

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Did as you said and viola!:sn:

However, what do you think the chances are of this?

I checked all my cables in the back. I had a red screen flash and thought, this wasn't right. So I replaced my Oppo HDMI and now all of sudden, I wasn't lacking in any color and in fact it dialed right in with room to spare.

Have you ever had an experience where a cable gives you trouble like that?

Thanks for your reply and help.

Now I can watch a movie this weekend and enjoy it.
 

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I have seen HDMI cables go bad over time ... ... and it isn't just sparklies ... it can be tearing as well ... among other things.

Regards
 
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