Problem with gamma who dives. - AVS Forum
Forum Jump: 
 
Thread Tools
Old 09-10-2012, 02:18 AM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi guys,
I have one big problem with my TV, my gamma dives and I don't understand why.
The greyscale is good.

I calibrate it with 20 point greyscale.

The TV is LG 60PA550T and the source is LG HX906PAN.

I use i1display 3 pro with calman 4.


The settings I have now on the TV is:
all extra stuff: off

Expert 1
Gamma: High
Warm

Contrast: 80
100% white 32ftl
I cant turn the Contrast down more because then the display 'll bee to dark.

Brightness: 48
I have calibrate it with DVE and the 2% black is good.


Check out my results at the img:
Bits123 is offline  
Sponsored Links
Advertisement
 
Old 09-10-2012, 06:11 AM
AVS Special Member
 
PlasmaPZ80U's Avatar
 
Join Date: Feb 2009
Posts: 7,291
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 112 Post(s)
Liked: 204
you can use the 20-pt controls to adjust gamma, just move RGB together up or down (in your case down to raise gamma at the bright end of the grayscale)
PlasmaPZ80U is online now  
Old 09-10-2012, 07:38 AM
AVS Special Member
 
airscapes's Avatar
 
Join Date: Dec 2008
Location: Philadelphia
Posts: 4,733
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 91 Post(s)
Liked: 130
Make sure your target gamma is set to what you want it to be in the Calman Settings. Right click your RGB balance bar chart and change reference form Relative to Absolute and make sure auto scale is checked. The chart will now have a 0 line. Take a 0 and 100% reading then adjust 100% so so RBG are as close to 0 as you can get them. now do the rest of the run. When complete your gamma will be perfect

What you have done is adjust the RGB so they are even with each other but you have made certain stimulus to bright and others do dark. If you had a data grid in your work flow, you could see how your Y data (how bright the stimulus is) does not match the target Y for the gamma you are trying to set (you set that in calman under option Target Exponent.

With the chart set to absolute you are including the Y target data for gamma.
airscapes is online now  
Old 09-10-2012, 09:28 AM
Member
 
1forsnow's Avatar
 
Join Date: Mar 2010
Location: Chicago
Posts: 188
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Liked: 41
what size patterns are you using? you could be having issues with ABL kickin in if the pattern is too big. Make a 10pt grayscale run and see where its at to see if there is a difference.

My .02
1forsnow is online now  
Old 09-10-2012, 12:23 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by 1forsnow View Post

what size patterns are you using? you could be having issues with ABL kickin in if the pattern is too big. Make a 10pt grayscale run and see where its at to see if there is a difference.
My .02

This could be an issue, or the contrast could also be a couple notches too high.

Or it might just be the way the display works, I've had TV's that just do that with gamma. Since I believe you have a 10 point control in that display, you should be able to tune that up so you get a flat response.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-10-2012, 03:36 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi,
I cant lower The contrast then The display Will bee to dark.
I got 2 point and 20 point settings.

I Will lab with The rgb.
Bits123 is offline  
Old 09-10-2012, 04:59 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Hi,
I cant lower The contrast then The display Will bee to dark.
I got 2 point and 20 point settings.
I Will lab with The rgb.
Quote:
Originally Posted by Bits123 View Post

Hi,
I cant lower The contrast then The display Will bee to dark.
I got 2 point and 20 point settings.
I Will lab with The rgb.

Too dark? How so?

There is no magical light output number to shoot for. If your contrast is too high, you won't have a good calibration till you lower it.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 11:12 AM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by sotti View Post

Too dark? How so?
There is no magical light output number to shoot for. If your contrast is too high, you won't have a good calibration till you lower it.


Yeh, but do you want to watch a plasma with like 20 ftl at 100 ire?

I'll try to stab the grey scale with absolute
Bits123 is offline  
Old 09-11-2012, 12:08 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Yeh, but do you want to watch a plasma with like 20 ftl at 100 ire?
I'll try to stab the grey scale with absolute

So what's it at now 22fL?
A couple click shouldn't take it from 35-40fL to 20fL.

It's either already too dark, or you can try taking a couple clicks off. If it's already too dark, then you're really looking at replacing the set.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 02:34 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Now I have calibrated with absolute in calman and the gamma is GREAT!

To get it perfect I needed to drop green at RGB some times buts that OK right?

At 70 IRE the blue was to high and I cold not get it mer down, but all in the grey scale is under 3 deltae.

I'm going to fixit some more later.

What do you think?


Bits123 is offline  
Old 09-11-2012, 02:39 PM
AVS Special Member
 
airscapes's Avatar
 
Join Date: Dec 2008
Location: Philadelphia
Posts: 4,733
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 91 Post(s)
Liked: 130
if you right click your deltaE chart and click autoscale you will be better able to find tune but sooner or later you will not be able to get it any better on click to much or to little and you are done. Glad you got it smoothed out!
airscapes is online now  
Old 09-11-2012, 02:41 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Now I have calibrated with absolute in calman and the gamma is GREAT!
To get it perfect I needed to drop green at RGB some times buts that OK right?
At 70 IRE the blue was to high and I cold not get it mer down, but all in the grey scale is under 3 deltae.
I'm going to fixit some more later.
What do you think?

Looks great.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 03:08 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thanks, I'm going to make it little smother later.

I have one quastion, now I first fix 100 IRE then I measure 0 IRE then I work my way down from 100 IRE to 5 IRE.
Is that the right way to go?

I guess that the greyscale and gamma 'll change a bit after the way, so to get the best results I need to measure it several times right?
Bits123 is offline  
Old 09-11-2012, 03:15 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Thanks, I'm going to make it little smother later.
I have one quastion, now I first fix 100 IRE then I measure 0 IRE then I work my way down from 100 IRE to 5 IRE.
Is that the right way to go?
I guess that the greyscale and gamma 'll change a bit after the way, so to get the best results I need to measure it several times right?

That's how our AutoCal works in CalMAN v4. With a good control, that should work perfectly fine, remeasuring afterwards can verify that.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 04:34 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Okej, i'll dubbel check it tomorrow.

My i1display sometimes goes crazy for like one mesure then it's ok again.
Shod I seend it for warranty back to xrite or is that normal?

Is The c6 much better?
Bits123 is offline  
Old 09-11-2012, 04:51 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Okej, i'll dubbel check it tomorrow.
My i1display sometimes goes crazy for like one mesure then it's ok again.
Shod I seend it for warranty back to xrite or is that normal?
Is The c6 much better?

That can be normal for measuring a plasma. It's a sync issue where we didn't quite get the exposure correct.

The C6 is a bit more accurate. It's typically faster because it has auto-exposure modes so it adapts to the amount of light it's measuring, faster in bright light, slower in the the dark. It's field upgradable so we can add display types for getting more accurate measurements on new display technologies as they roll out.

For a home user, I don't know that you'll see a huge improvement moving to a C6, for pro calibrators that see lots of different types of displays, it's incredibly handy. Also the C6 is NIST certified, which can be a requirement for Pro calibrators for certain types of jobs.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 04:55 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Ok, so The i1display 3 is good for me then?

In My country it's not many pros so i have some thouths to make The isf cert and start with it.

If i buy The c6 do i need to buy calman again?
It's like 6 months old.
Bits123 is offline  
Old 09-11-2012, 05:16 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Ok, so The i1display 3 is good for me then?
In My country it's not many pros so i have some thouths to make The isf cert and start with it.
If i buy The c6 do i need to buy calman again?
It's like 6 months old.

No you don't need to re-buy CalMAN, but we do have a few different license levels.

You'll want to have CalMAN 5 when that becomes available. It's already out for Professional Calibrators, but the home product will be out any day now. If you do decide to start doing professional calibrations, you would need to upgrade to one of the CalMAN 5 for Business products, there are many features specific to the business product for customer management and reporting that are essential to the working calibrator. So you may need to pop for an upgrade if you decide to start a business, but businesses always have start up costs.

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-11-2012, 05:22 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thanks for The info.

I own 3 copirations in sweden, it's like english ltds but in sweden The companys needs an account balance at minimum 16.000 dollar for each company Else The goverment declar The company bank-rupsi.


So i know whats The cost is.

Do you have some licens edications in The us?
Bits123 is offline  
Old 09-11-2012, 05:26 PM
AVS Special Member
 
sotti's Avatar
 
Join Date: Aug 2004
Location: Seattle, WA
Posts: 6,640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Liked: 175
Quote:
Originally Posted by Bits123 View Post

Thanks for The info.
I own 3 copirations in sweden, it's like english ltds but in sweden The companys needs an account balance at minimum 16.000 dollar for each company Else The goverment declar The company bank-rupsi.
So i know whats The cost is.
Do you have some licens edications in The us?

All of the information about CalMAN 5 for Business is here:
http://commercial.spectracal.com/

Joel Barsotti
SpectraCal
CalMAN Lead Developer
sotti is online now  
Old 09-12-2012, 10:41 AM
AVS Special Member
 
Doug Blackburn's Avatar
 
Join Date: May 2008
Location: San Francisco - East Bay area
Posts: 3,457
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
Liked: 228
There is no such thing as 'IRE' in digital video... in spite of calibration software and video processors continuing to use it (incorrectly). IRE is an analog video standard/measurement that defines a white/gray level given versus input signal voltage.

This has been a public service announcement from the Society to Eliminate References to IRE in Digital Video (SERIREDV).
wmwilker and PlasmaPZ80U like this.

"Movies is magic..." Van Dyke Parks
THX -- ISF -- HAA
Doug Blackburn is offline  
Old 09-12-2012, 01:22 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Damn, Today when I re mesured my display I got this results:




Then I started to fix it and got this:




Then direct after I was done calibrating I re mesured it again and I got this:





Why is that?
I can't understand it....


I had my TV on for like 30 minutes before I started re-mesuer I also had my i1display 3 on the screen for like 30 minutes.



Tomorrow I'll factory restor my display and try again.
It's a LG 60PA550T with the newest FW

I use:
i1display 3
Calman 4 newest version.
AVS BD disc
Window

Calibrat with 20 point


First I start to calibrate 100 IRE then I read in 0 IRE then i start at 95 IRE and work my way down.


Edit:
The only thing I did diffrent from yesterday is that my TV had been on for like 4h before yesterday and today It was only 30 minutes before.
I'll tray calibrate it again now and se the results.
But please write if I do something wrong.
Bits123 is offline  
Old 09-12-2012, 01:46 PM
AVS Special Member
 
Chad B's Avatar
 
Join Date: Oct 2002
Location: Piqua, OH
Posts: 2,126
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 103 Post(s)
Liked: 504
It's fatigue from having the same size window up on the screen too long. Some plasmas, esp LGs, are picky about that. Put up a full white field, DVD menu, or some completely different screen up immediately before taking the measurement run and also every 5 minutes or so while calibrating.

ISF/THX calibrator with Jeti 1211 reference spectro
Latest reviews:LG 65UB9800Samsung UN65HU8550UN65HU9000, UN85HU8550, LG 55EC9300, LG 55EA8800 (including 3D)

Why I don't publish settings, Review index and rankings, Florida tour Dec '14, Texas tour Jan '15
Chad B is online now  
Old 09-12-2012, 02:13 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Ok thanks, I put colour wash on for like 30 seconds between every reading and so on.
Let's see how it goes now.
Bits123 is offline  
Old 09-12-2012, 02:15 PM
AVS Special Member
 
airscapes's Avatar
 
Join Date: Dec 2008
Location: Philadelphia
Posts: 4,733
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 91 Post(s)
Liked: 130
If not the TV doing it, it can be a VERY small difference in the reading of 100%. This is something I think they changed in Calman5 If I take continuous readings of 100% with my C6 the Y will bounce up and down as much as 4% and that is within meter tolerance of 2%+- This small change will make your gamma change a the top end like that I took 60 runs on my DLP projector and got 60 different results,t every one was different and nothing changed but the readings the meter took. I would recheck and do as Chad says, but if that does not help, it is probably just the repeatability tolerance of the D3 and how calman4 calculates gamma.

To see if it is the meter difference do the gamma run as chad says, and when you to 100 at the end of the gamma run take another reading of 100 and then another and if the chart moves around then it is the just the meter tolerance and the way gamma works in Calman4
airscapes is online now  
Old 09-12-2012, 04:03 PM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi again, new pictures of the new calibration.
I took two diffrent pictures when I mesured after.

Calibration:


After 1:


After2:




So what do you think? Now I have been using colourwash to adjust under the time i calibrated.
Now the after mesurments looks much better.

But still, they diffing.
When I do the after readings I just use colurwash before because the readings goes fast.

Is it the diff in the i1display 3 or shod I dive in and try to fix the greyscale some more?
Bits123 is offline  
Old 09-12-2012, 04:15 PM
AVS Special Member
 
PlasmaPZ80U's Avatar
 
Join Date: Feb 2009
Posts: 7,291
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 112 Post(s)
Liked: 204
Quote:
Originally Posted by Doug Blackburn View Post

This has been a public service announcement from the Society to Eliminate References to IRE in Digital Video (SERIREDV).

lol biggrin.gif
PlasmaPZ80U is online now  
Old 09-12-2012, 04:18 PM
AVS Special Member
 
PlasmaPZ80U's Avatar
 
Join Date: Feb 2009
Posts: 7,291
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 112 Post(s)
Liked: 204
Quote:
Originally Posted by Bits123 View Post

Hi again, new pictures of the new calibration.
I took two diffrent pictures when I mesured after.
Calibration:

After 1:

After2:

So what do you think? Now I have been using colourwash to adjust under the time i calibrated.
Now the after mesurments looks much better.
But still, they diffing.
When I do the after readings I just use colurwash before because the readings goes fast.
Is it the diff in the i1display 3 or shod I dive in and try to fix the greyscale some more?

plenty close enough/effectively perfect

if you are really concerned about RGB balance (grayscale color) errors, use dEUV instead... if everything is still under 3, you're fine
PlasmaPZ80U is online now  
Old 09-12-2012, 05:03 PM
AVS Special Member
 
Chad B's Avatar
 
Join Date: Oct 2002
Location: Piqua, OH
Posts: 2,126
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 103 Post(s)
Liked: 504
LG plasmas with the 20 pt adjustment are very finicky, as you're finding. I think a 10 point adjustment would have been better suited to it. Regardless, your results look very good. The small blip at 55% is probably a meter sync issue, since it goes in the opposite direction on the 2 after measurement runs.

ISF/THX calibrator with Jeti 1211 reference spectro
Latest reviews:LG 65UB9800Samsung UN65HU8550UN65HU9000, UN85HU8550, LG 55EC9300, LG 55EA8800 (including 3D)

Why I don't publish settings, Review index and rankings, Florida tour Dec '14, Texas tour Jan '15
Chad B is online now  
Old 09-13-2012, 05:47 AM - Thread Starter
Member
 
Bits123's Avatar
 
Join Date: Nov 2010
Posts: 34
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
If I deside to fix gamma at 50IRE to 100 IRE 'll I mess the gamma upp at 50 IRE to 0 IRE?

I just want it perfect.
Bits123 is offline  
 
Thread Tools


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off