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That's exactly the point, you can't. But as we have discussed, i feel multiple reads at 100% for about 5 seconds will give you a better idea of peak brightness than a single read.
That was the case on my 55" CX. At that latter stage of the Autocal, the nits did indeed creep up slightly with each read until about 4 reads for me.
 

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When you measure peak brightness you need to put up a 10% window and continuously measure for about a minute or two. You will see PB start to rise and it will eventually stop. That's what your PB is. My guess is if first read is 600 nits you will probably peak at around 650-675 nits which is fine. From my experience the 48 inch LGs usually measure less than the other OLEDS and there is a lot of panel variability. The other thing to check before you do any testing is the White Point. Set it to D65 or whatever you like and then measure. You can use the 2pt controls to set it for a quick test.
Yeah I've measured steady state peak brightness, it's actually 635 nits max for 10% but the true near-PQ coverage ends at about 570 nits, above which it sigmoids towards max, kind of similar curve to BT.2390.

I have tested the whitepoint and corrected it to true D65 with service menu "mean" high point (for modes where white point cannot be corrected further) then 2-point calibration on top of that where I could.
This was with i1Studio spectro, in Judd & Voss reference which matched best visually to lightbox by my eyes for many screens. i1 Display Pro also has no issues profiling the screen.

10- and 22-point grayscale is worthless as it introduces serious visible banding and also measured with the spectro - oscillating color temperature. Wasted many hours on attempting something smooth there.

The TV also applies this on top of 2-point, which is interesting.
TV also needed a tint skew set to G8 so that secondaries match their locations more accurately. Magenta is still a bit off.

I have no idea why LG disables so many options in PC mode or even in Standard (non-Game) mode in non-PC. The CMS secondary tuning options in it would be rather useful.

Saturation tracking is a tiny bit oversaturated at 50, with a shallow U shape, middle being accurate. I haven't attempted correcting that.

Apparently I'll have to shell out for Calman to make it more accurate. (Lightspace is too rich.) Or live with ICC off DisplayCAL.
 

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So you said a lot in this post. The only thing i want to comment on is calibrating HDR and DV. It's very difficult to calibrate these picture modes except for the 2pt in the SM or in the user menu and maybe a couple of points that Liberator72 talks about because the tone mapping is enabled and the set is very unstable with all the high luminance patches. For many years we tried to calibrate these PMs manually and you are always fighting the tone mapping and every other variable. This is why CM worked with LG to develop a process to calibrate the grayscale and CMS for HDR with the tone mapping turned off. There is lot's of discussion and opinion on using the CM autocal process pro's and con's and i don't want to go there since that's all been discussed ad nauseum and everyone has their own preference. And i'm not saying you can't manually calibrate these PMs. Many have their own special process to get relatively good results from lot's of experience working with these PMs. All this said, you need to try the different calibration approaches and see which works best for you with the equipment you have.

I also want to add, as far as HDR peak brightness, i've seen panels that measure all over the place but as long as you are in the 600 nit and higher area you are probably ok because in reality, unless you have a reference to compare to your eye isn't going to see any difference. LGs HDR PQ is very impressive.
 
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@WiFi-Spy hey Tyler, can the r2 beta shadow detail feature be applied to Dolby vision? In your video you mention sdr and hdr but not dolby vision.

Also, do I need to completely redo all of my autocal for the shadow detail, or can I just reconnect the tv and go right to shadow detail without changing anything?


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@WiFi-Spy hey Tyler, can the r2 beta shadow detail feature be applied to Dolby vision? In your video you mention sdr and hdr but not dolby vision.

Also, do I need to completely redo all of my autocal for the shadow detail, or can I just reconnect the tv and go right to shadow detail without changing anything?


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I spoke to Tyler about this and yes you can use the shadow detail control for DV when you use the autocal process.
 

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I spoke to Tyler about this and yes you can use the shadow detail control for DV when you use the autocal process.
I've been experimenting with this a bit this arvo, on DV Cinema Home (I know), but autocal can calibrate it, apparently.

The default shadow detail point and and shadow detail value were apparently 0. Using Masciola's Dolby Vision Black Clipping pattern, nothing I change the values to will get the bars to flash below Bar 36 (maybe 32 — my environment isn't pitch dark right now). If I switch over to (previously-calibrated-without-shadow-detail) DV Cinema mode, it looks basically the same.

So I was expecting to see raised blacks in Dolby Vision, and it seems I've found crushed blacks which the shadow detail controls can't touch? According to the manual, Bar 4 should be just visible. It seems I'm at least missing steps 4, 8, 12, 16, 20 and 28.

I'm pretty sure the controls are applying, because I can see the brightness of the last visible bar changing along with my adjustments... so that's where my extremely amateur self is at with the the Calman 2020 R2 shadow detail controls on DoVi.

EDIT: Well... after restarting the TV I think my shadow detail settings actually applied fully because the blacks are now insanely raised and it's a full-on chrominance overshoot party on Netflix with this picture mode. Whoops!
 

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I spoke to Tyler about this and yes you can use the shadow detail control for DV when you use the autocal process.
Thanks John!


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Hi guys

I’ve attempted to do another SM White balance manual calibration, as it worked fine the other day.

Attempting today, it just does not seem to be producing good calibration results. I calibrate the 100 White to a successful 0.1de, but between 20-90 on the greyscale I have a very weird high errors sloping downwards

My colors have high errors too, and the values seem identical pre and post calibration

Anyone have any idea why this is happening? My TV is factory reset and Calman reinstalled.

pic included to show results
3047450

Thanks guys!
 

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Please do not cross-post the same question in multiple threads. Jrref responded to you in the CalMAN for LG thread...
 

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I want to calibrate my CX. Is there any difference in accuracy between i1Display Pro Retail / OEM / Plus versions? Since I don't need to measure more than 1000 nits and the retail version is cheaper.
 

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There are differences between individual meters, even within the same line, but no published difference in accuracy between those model lines resulting from design changes. In other words, the answer to your question is "no".
 

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How do calibrators generally go about reducing contouring/banding gradient artifacts?

I was having a look at Masciola’s radial gradient test patterns on autocal’d HDR and DoVi modes. HDR had some banding on particular colors, while DoVi had quite a lot on most colors and white.

The white in particular is clearly visible in a lot of content. The Apple TV+ title card is an easy to find example.
 

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Here you can change Saturation/Luminance Level.
Got myself an i1 Display Plus. I have read that with OLED, positioning it about 6 inches away from the screen is better than contact because of the heat of the screen. Is this a method you would recommend? Also, do you think RAW XYZ mode would be more accurate than profiling to a 7 year old i1 Pro-2 that has been well taken care of, but has not been recalibrated by X-Rite?
 

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You can use the i1PRO2 to create a meter correction table for your i1Display PRO.

Then continue the full calibration using your profiled i1Display PRO.

That process will improve your i1Display PRO color accuracy, see.
Tedd, could you please list the proper Calman settings for doing a profile with the i1 Display Pro Plus, and the i1 Pro-2? I'm unclear about some of the settings like Raw XYZ, and WRGB OLED. How about low light handler? Any help in this area would be so very much appreciated.

Also, I'm trying to calibrate my PC mode Game Preset on my LG CX. I'm using your disc (The Calman patterns) so what should I use to play them in my PC that will not effect the patterns? VLC media player seems to cause the 80% to 90% to go all wonky. What can I use to keep your files bit perfect while calibrating my Game mode on my PC?
 

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I've been experimenting with this a bit this arvo, on DV Cinema Home (I know), but autocal can calibrate it, apparently.

The default shadow detail point and and shadow detail value were apparently 0. Using Masciola's Dolby Vision Black Clipping pattern, nothing I change the values to will get the bars to flash below Bar 36 (maybe 32 — my environment isn't pitch dark right now). If I switch over to (previously-calibrated-without-shadow-detail) DV Cinema mode, it looks basically the same.

So I was expecting to see raised blacks in Dolby Vision, and it seems I've found crushed blacks which the shadow detail controls can't touch? According to the manual, Bar 4 should be just visible. It seems I'm at least missing steps 4, 8, 12, 16, 20 and 28.

I'm pretty sure the controls are applying, because I can see the brightness of the last visible bar changing along with my adjustments... so that's where my extremely amateur self is at with the the Calman 2020 R2 shadow detail controls on DoVi.

EDIT: Well... after restarting the TV I think my shadow detail settings actually applied fully because the blacks are now insanely raised and it's a full-on chrominance overshoot party on Netflix with this picture mode. Whoops!
So, the Black Crush when using the 2020 iTPG has not been resolved yet.
Is there any way to get around it other than to use the 2019 iTPG?
As I understand the Shadow Detail compensation only works with the 2020 iTPG, which means improved shadow detail but crushed blacks.
Are there any plans to fix this bug?
Is it a problem on LG's end or can Portrait Displays do something about it?
Maybe @WiFi-Spy can clarify.

As far as I know it is not recommended to change the brightness controls after calibration.
And even if I do, I never get any bars below 32 to flash in Masciola's DV pattern after a DV Autocal. It seems like DV calibration using the 2020 iTPG completely cuts off the low end. The bars do flash on uncalibrated PMs down to around 16.

Is it really true that we should see the bars flashing down to 4?
I asked an owner of a Panasonic OLED. He can see it down to 12 with the most accurate picture mode, so maybe flashing down to 12 or 16 is fine.
Sadly, an LG CX using the 2020 iTPG to autocalibrate DV clips all blacks below 32.

Sidenote: I activated the low light handler. Can that be responsible for any black crush?
 

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So, the Black Crush when using the 2020 iTPG has not been resolved yet.
Is there any way to get around it other than to use the 2019 iTPG?
As I understand the Shadow Detail compensation only works with the 2020 iTPG, which means improved shadow detail but crushed blacks.
Are there any plans to fix this bug?
Is it a problem on LG's end or can Portrait Displays do something about it?
Maybe @WiFi-Spy can clarify.

As far as I know it is not recommended to change the brightness controls after calibration.
And even if I do, I never get any bars below 32 to flash in Masciola's DV pattern after a DV Autocal. It seems like DV calibration using the 2020 iTPG completely cuts off the low end. The bars do flash on uncalibrated PMs down to around 16.

Is it really true that we should see the bars flashing down to 4?
I asked an owner of a Panasonic OLED. He can see it down to 12 with the most accurate picture mode, so maybe flashing down to 12 or 16 is fine.
Sadly, an LG CX using the 2020 iTPG to autocalibrate DV clips all blacks below 32.

Sidenote: I activated the low light handler. Can that be responsible for any black crush?
I should clarify a few things:
  • I'm not aware of the internal pattern generator versions having any affect on HDR/DV shadow detail, specifically. Maybe someone else mentioned that but it hasn't been my experience. I do know many reported the 2020 iTPG producing bad reads and resultant grayscale errors on DoVi autocal runs since a recent firmware. Most, including me, had written it off and have been using iTPG 2019 for DoVi on CX. Since this new Calman DLL, though, iTPG 2020 seems to be working properly (for me).
  • At least two people on this forum (I think) have suggested the raised black problem with Dolby Vision is in Dolby's court to fix and will perhaps come in a future LG CX firmware when ready. I've seen nothing official about this issue from LG, Calman on Dolby thus far. Not seen too much discussion of black crush in DoVi in my short time on the forum but I suppose they're not mutually exclusive.
  • Having rechecked with Masciola's patterns in a properly darkened room, it looks like my auto-calibrated DoVi modes both flash as low as 20, though there doesn't seem to be much difference between 20+24 at all in terms of luminance. 28+32 seem too similar as well. Only one of these modes I attempted to adjust the shadow detail for in Calman, yet the results appear identical to my eyes.
  • I did a picture mode reset on one of my calibrated DoVi modes with the test pattern running and it seemed that all the visible steps got brighter, with the final flashing bar now being 16 on the factory LUT.
  • I've been using the low light handler as a matter of course for all my autocals simply because I saw it recommended here so often. Can't really comment further.
Either way I don't let any of these niggles hamper my enjoyment of the TV. Learning a bit about ISF calibration is its own reward and its satisfying to experiment. I know the picture will never be perfect. It's close enough already and each little level-up with extra shadow detail or whatever is just gravy.
 

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For Dolby Vision, in addition to calibrating manually, you can calibrate Cinema with the CM process and if you want, try the shadow detail control. Either way until we get the DV fix from Dolby, whatever you get should be good enough for now. For DV Cinema Home and Game, LG incorporates an "offset" to make the picture brighter so these PMs won't follow PQ. If you try and calibrate them, you will remove the offset, not sure if this is the right term, the PM will follow PQ and the brightness will be the same as Cinema. So i recommend for DV Cinema Home and DV Game, just set the WP in the service menu or use the 2pt then in CM, select the PM but don't do a reset, skip the gray scale and just create a new config file and load it. Do this in DV Absolute mode if you have an external TPG. With the iTPG, i'm not sure which test patterns it's generating so if you are unsure, just make sure the WP is set and skip the config file. Both these PMs are not reference so just setting the WP should be good enough. FYI, if you set the WP in the SM with SDR at the beginning of your calibration, the WP in DV should be very close. You can measure and then fine tune if needed using the 2pt once you get to your DV calibration.
 
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Is it really true that we should see the bars flashing down to 4?
The bars in R.Masciola's DV Pattern suite will indeed flash all the way down to Code Value 4 (0.4%) but they will be very, very difficult to see at that level without using some form of magnification.

Ryan's patterns are provided in Full Range, so 0 - 0% will equal 0.0000 nits, true black. On my LG OLED and all others I have calibrated, after a manual calibration in Dolby Vision, this means no sub pixel activity at all. Black is indeed Black.

Code 4 - 0.4% will equal (IIRC) 0.0004 nits. Which will be very, very difficult to see with any surrounding light, even the light from the other flashing bars in that pattern. However, by magnifying with a 30X Jewellers Loupe, it is indeed visible (while 0% remains black).

Below is an image captured with an iPhone XS with Brightness raised to 51. This has lifted the black floor (background is now of course above black) but it accentuates the fact that 0.4% does indeed differ from 0%. Depending on the display you view this on, you may or may not see it. On my iPhone and iPad it can be seen quite clearly, but on my notebook (with very poor black levels) I can't differentiate below 1.2% in this image.

Ignore any colour cast you may see in low light bars. It is a result of the combination of the raised brightness setting and overexposed image capture to try and show that the bars do indeed illuminante in the correct stepped fashion. This colour cast does not appear in real world viewing.
3048360


The clipping of black from approximately 3.1% and below is a known by-product of loading a custom 1D LUT in Dolby Vision. It is possible that the new Shadow Detail control can somewhat mitigate this a bit, as described by this comment.

Having rechecked with Masciola's patterns in a properly darkened room, it looks like my auto-calibrated DoVi modes both flash as low as 20, though there doesn't seem to be much difference between 20+24 at all in terms of luminance. 28+32 seem too similar as well.
That's pretty much all I want to say about that feature though, as I am sure there will be others that will comment about it at a later date.
 

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I was lucky enough to get access to the calman r2 beta which has the shadow detail feature. I was able to use mehanik's c65 hdr pattern to dial in HDR cinema mode properly.

I am trying to autocal HDR game mode now, but the issue is, if I access the pattern while in hdr game mode (my ps5) which is on a thumb drive, it reverts to HDR cinema, and I cant invoke hdr game from the thumb drive.

In anyone's experience, would it be safe to apply the same shadow detail values from HDR Cinema to HDR game, or would I be better off leaving them at default since I cant figure out a way to get an HDR pattern to display while in HDR game mode?
 
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