A newbie who seeks to learn TV calibration - need advice

Home Theater Lobby
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Hi everyone,
New here. Got here by searching articles on DV profiles.

I want to learn about TV calibrations but I don’t know where to start. There is a lot of info out there, but I feel I don’t know how to structure the information and apply it. Feels like a mess.

I’m usually using my i1 Display Pro to calibrate my PC monitors, but I can’t say I understand much about what I’m doing.

Can someone please direct me in the right place, i.e., where to start and apply knowledge about calibration? if such exists…

p.s. - I know that for proper TV calibration, there is more expensive and required equipment. I’ll get there one day :slight_smile:

Thanks!

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Welcome…you will need to purchase a calibration s/w like Chromapure and a better colorimeter than the current one you are using. Upgrade to iDisplay Pro 3 at the very least. You can order this package from this site: X-Rite EyeOne Display 3 Colorimeter with ChromaPure. Take some time to see the demos on how to use Chromapure s/w…get familiarize with its user interface and some of its features.

I have had bought many video calibration stuff including my new toy - the Lumagen Radiance Pro 4242-C Video Processor from this site in the past and never have any issue.

Once you have gotten the package, then we’ll talk about how to calibrate…

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Thank you.
For now, I would like to keep using my i1 display pro, due to budget issues (corona and such) and learn within this budget limitation up to the point where I can no longer proceed because of limited equipment if that makes sense.

Is there a different free software for now, that I can use to learn?

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First and foremost, you did not mention what kind of TV you have? OLED? LCD? etc. If you want your 4K TV to be properly calibrated, some form of calibration s/w is a must-have, meaning you need to spend some $$$ to get a better image.

Two important things need to be present - 1) Pattern generator and 2) computational power found in the calibration s/w to determine how much calibration is required to achieve reference results - e.g. what is the correct primaries (Red, Green & Blue) and secondaries (Cyan, Yellow & Magenta). The calibration of White Balance is extremely important to achieve color accuracy based on the pre-defined standards - e.g. Rec 709 for SDR content like bluray disc as an example. Once the White Balance is measured properly, gamma is another segment that you just can’t do it by “eye-balling”. You will need a dedicated calibration s/w to get it right at different IRE levels. A google search shows up a free calibration s/w styled, as DisplayCal - you may want to check it out since it is free here at https://displaycal.net/. I have never use it before myself, so you may want to d/l it and try for yourself, who knows, it may work for you :slight_smile:

If you want to save money, I recommend ensuring basics like Black and White levels are properly dialled in. Use of color decoder (blue filter) to dial in Hue and Tint correctly. Some TV tends to have a red or green push and this color decoding correction may fix it, though rarely in use these days. If your TV is a Sony, select Reference level for your Picture setting before performing all those mentioned above.

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Thanks for the details explenation.

I have LG CX OLED.
I use Dispcal GUI for my PC, but I don’t know what I’m really doing there. I couldn’t find a useful guide to help me understand what every setting does.

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You need to learn the fundamentals first…Go read up the literature on the following to have a better understanding.

On White point (Balance) - ChromaPure Video Calibration Software
On Gamma - ChromaPure Video Calibration Software
On Contrast - ChromaPure Video Calibration Software
On Delta-E - ChromaPure Video Calibration Software

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I read it all, twice. I really enjoyed it and learned quite a lot.

May I ask, what do you think would be follow-up articles to read?

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You don’t need to read up more articles as long as you truly understand the the 4 important calibration pointers. Always start off with White Balance. A good colorimeter is important to ensure 15% and 10% IRE black levels can be properly measured.

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Why 10% and 15%?
I have the i1 display pro, but it’s revision A (2012 model).
I don’t understand the following when it comes to OLED:

I’m digging into many articles to get familiar with calibration and many of them don’t mention OLED and what are the ‘gotchas’ with OLED.

  1. For OLED and HDR/DV - Do you select a colour space of rec.709 or bt.2020? Is it even a choice you can make in a calibration software? Readin here: Unravel | Understanding Color Spaces wouldn’t BT.2020 be a better colour space to target with calibrating the CX? While it won’t encompass the entire BT.2020 gamut, it should be wider than Rec.709. Isn’t that prefereable?

  2. What is the more appropriate or widely chosen Gamma for Day and Night viewing? I see that some recommend 2.2 for day and 2.4 for night (Expert bright/dark), but why not BT.1886 for both? Why not BT.1886 instead 2.4 for Expert Dark? Given this article: Unravel | Understanding Gamma at the bottom of the page, seems BT.1886 is better than 2.4.

  3. The color space options auto/wide/extended - the recommendation is always Auto. How can I assert the TV is picking the correct color space? When I toggle between the three, I see they all produce slightly different colors. What test can I perform to assert that for a given source, the TV is selecting the correct color space?

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First and foremost, let me preface by stating I don’t own a LG OLED CX model as such I am unable to advice what is the correct setting to use for calibration. But what I can offer are my insights to your queries.

For your first query on colorspace BT709 or BT2020, which to choose for calibration. Basic principle of calibration, stick to what the display can best display. More often than not, BT709 calibration is the easiest to achieve. Do this first and get your white point, grayscale and gamma on point first. Watch some of your fave bluray titles or Netflix clips streamed in 1080p and judge for yourself how good or bad the image quality after calibration. I can almost guaranteed that none of the consumer-grade display, be it OLED TV or even high-end 4K/8K projector can do a 100% P3-DCI, let alone BT2020. If your display can do a wider color gamut with good color rendition when playback in 4K AFTER you have calibrated for BT709, then you can consider to do a secondary calibration for HDR/DV viewing. If not, I will not bother to do any HDR calibration if you do not have a good colorimeter that can read high gamut (color) intensity from a 4K HDR test pattern. So what do you do then if you can’t do a proper 4K HDR calibration? Like I say, no need to do it. Just calibrate BT709 and ensure let the TV display take over whenever 4K HDR content is being played. You should be able to get very good 4K HDR image with just BT709.

For your second query on which gamma to choose - i.e. 2.2, 2.4 or BT1886 (close to 2.35). For BT709 calibration, you can choose either BT1886 or 2.4 (if you have a man-cave). You can stick to one gamma for both day or night ISF setting if you choose to. For me, I don’t play with ISF settings, I only use one gamma (2.4) for both my SDR and HDR calibration. Of course, you choose BT1886 if you prefer a “more balanced” gamma that sits between 2.2 (some considered too low which may cause the image to lose out on its contrast and make the image less punchy) and 2.4 (enhances black levels whilst w/o sacrificing too much shadow details).

For your third query, the nomenclature used in color space varies from display to displayt. For instance, “Auto/Wide/Extended” is equivalent to “BT709/P3-DCI/BT2020”. If you are going to do a BT709 calibration, select “Auto” should yield more accurate color settings. Choosing a good base color space is important to ensure proper white balance can be achieved. Once white point is accurate, everything else like gamma and grayscale and even colorimetry (CMS) will fall into place with good delta-E error.

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Thanks for the detailed reply.

I agree with trying to firstly get SDR with Rec709 dialed in, before going to HDR/DV.
Also, it is true that no consumer TV can achieve BT2020.

Given the above statement, if it is known that the LG CX can achieve more than Rec709, but less than BT2020, wouldn’t it be better to try to calibrate to BT2020 because it can achieve more colour volume?

Why is this confusing?
Since according to articles I read, Rec709 was developed for HDTVs while BT2020 is more for 4K/8K. True, they cannot cover this gamut, but some can cover more than Rec709.
In addition, 90% of the content I’m watching is 4K and not FHD.

I’m not in disagreement with you, I’m just explaining why I am confused based on what I read (Use BT2020 for 4K) when comparing to instructions on how to calibrate (Use Rec709).

When I reach HDR/DV, is this when BT.2020 should be selected in calibration software?

I watch movies in a completely dark room (man cave). I have bias lights, but I find it not very useful on an OLED TV.
This CX model offers 2.4 and BT.1886, they are exactly the same on an OLED TV. I believe they will produce different results on LCD-based TVs.
I read that BT.1886 should be more natural tracking than say 2.2.
So, in this case, my confusion is if the TV allows for BT.1886 and it supposed to be the “better” gamma selection, why isn’t that being widely used when I read or watch calibration tutorials. I watch “how to calibrate the LG CX” by Portrait Displays using LG Calman, and they always use Gamma 2.2 and I don’t understand why not BT.1886.

I’m not suggesting this is better than that. It’s about understanding the “Why” behind such decisions which are not explained in these tutorials that causes my confusion. If I use my i1 Display pro and LG Calman, I wouldn’t know what is the correct gamma to select.
Would BT.1886 for dark room viewing and 2.2 for bright room viewing is a better approach? Or use BT.1886 for both and just increase the OLED light for light room and decrease OLED light for dark room?

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Ok…if you really want to talk about proper 4K HDR calibration, then I will have to ask you to invest in a better colorimeter and get hold of a calibration like Chromapure or Calman…then we can have a proper discourse (no pun intended) on HDR calibration…If my understanding from you previous post is correct, you will want to stick to the use of your current colorimeter and not going to spend on a calibration s/w like Chromapure or Calman for now? Correct me if I’ve misinterpreted.

As mentioned in my latest post, my context of calibration is from a projector perspective and NOT OLED TV which I have very little to no experience. I am speaking in a more general terms when it comes to display calibration.

By and large, each calibration s/w has its own ways to calibrating a 4K HDR content…for instance, my experience is with Chromapure and so I can only speak from my own experience when using it. As you are aware, I am using a Lumagen Radiance Pro as both a scaler as well as a test pattern generator to calibrate both BT709 and BT2020 for SDR and HDR content respectively…I can tell you, both Lumagen guy and Chromapure creator suggested to me 2 different ways of calibrating 4K HDR…for instance, Chromapure suggested to me to use gamma “HDR 10 for Projector” (Preset - which purportedly to be using the ST2084 PQ curve) and select color space to be BT2020…unfortunately, the result didn’t turn out well. So I followed Lumagen’s advice to use SDR2020 - i.e. BT2020 within a SDR container instead of HDR10 container. As we are using SDR container for calibrating HDR content, we are able to get the color intensity to 100% for accurate color reading since the intensity has been somewhat attenuated for the probe to pick up and provide a much more accurate reading. The gamma instead of using the ST2084 PQ curve as suggested by Chromapure creator, I opted to use Power Gamma 2.4 since I am no longer using PQ Curve for gamma calibration because it is now in SDR container. This make calibration much easier.

For TV, you really have to start doing calibration yourself to find out more…by reading, you only see half the picture but you need to do it to understand why it is written in this manner - e.g. why BT1886 and not Gamma 2.2 or 2.3 or vice versa. All these queries can only be answered when you start doing it.

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Short answer, yes I’m planning to upgrade my i1 display pro and buy a proper TV calibrating software capable of calibrating 3DLUT, DV and HDR.

I’m waiting up for a few photography assignment to save up for the i1 Display 3 Pro Plus (capable of better low light handling accuracy suitable for OLED and 2000nits brightness) and either Calman LG home or LightSpace CMS.
The LightSpace CMS will require me to source a pattern generator for DV/HDR but it is a lifetime license and can be used on any TV.

The Calman LG Home is only for the LG TV and allows software upgrades for 1 year only. The upside is the LG TV has a built-in pattern generator for DV/HDR/SDR and Calman can trigger it, saving costs on buying a pattern generator.

Not sure which software I will buy. Chromapure is also a viable option in the list of software.

In the meantime, I’m trying to educate myself on the theory and practices used in this industry so when I go in and experiment with my existing i1 display pro from 2012, I get some hands-on practice but not expecting accurate results.

I agree with your statement about “start doing calibration”. In the meantime, I practice on my PC monitor, which is clearly not the same, but it allows me to learn why choosing one setting over the other and how to read the reports.
When opening a calibration software, there are many options. Simply diving in won’t help in this case.
I might do more harm than good. Unless I have some calibration guru next to me, I prefer to educate myself as much as I can so when I do open up a calibration software, I understand which options to select and what’s the reason behind them.

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:+1:

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Bro Des
If one were to get into calibration at home, what is the simplest product that is close to idiot proof that you would suggest?
I think the main challenge is the complexity, and second the cost that deters more members from doing this, thanks

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Being a newbie in TV calibration, I do have some experience in PC monitor calibration.

I don’t think there’s a simple product really, but the closest thing that comes to mind is the X-Rite i1 Display Pro. There some variants of the Display Pro, but the i1 family of products is widely used by professionals and hobbyists as one.

For TV calibration, the “easiest” one is a product from Portrait Displays, but it has its issues.

What I found to be really important is the support you’re getting from the people behind the product and the community as well.
Seems that on another forum, there is a product that gains more popularity from the community, lots of support, and better overall product improvements over time.

Mainly speaking about TV’s, the products you’ll need are: A very good light meter (colorimeter), a calibration software, a laptop and a pattern generator.

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That is correct. It applies to projector calibration as well. The key is test patterns. For calibration of BT709, almost all display can do 100% faithfully. It’s the HDR calibration that requires some tweaking. But before you can do that, a good colorimeter coupled with a good calibration s/w with built in pattern generator all in one is a must.

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It can be taught. If one is willing to learn. :grinning:

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I’m with you on this.
Look, I’m considering myself a tech-savvy. I love gadgets. I build my own PCs. I’m a professional photographer who also teaches photography and photoshop and colour aware workflow, using colour checkers and calibrated monitors. I’m an electronic engineer by education. I work in IT.

But when it comes to TV calibration, I got very very confused. Put price aside, there is no coherent way to acquire this knowledge in one-stop-shop. It’s a bit all over the place.
It also seems that learning and applying knowledge are two different things.
Theory definitely helps, but the practice is something else.

Each software is loaded with loads of buttons and menus and submenus and you don’t really know what to select and why. Which is the best hardware to use. What is the correct workflow, etc.

But I’m not writing this post to deter you away from this. I decided to be persistent and ask to be guided, till I get to the point where I can start applying the knowledge.

So to help you with that journey, I can share what I have got so far.
Start with the links in this thread that desray kindly provided. They help a lot. Any word or terminology you don’t understand, google it or ask here.

Focus on SDR for starters, and later move on to HDR/DV.

As for hardware, mainly speaking about pattern generators. They are expensive, but there’s a cheap solution if you’re willing to pay with time and brainpower.
Over a different calibration forum, you can find a post dedicated to using Raspberry Pi as a bit-perfect pattern generator. You hook it up to the monitor/projector and this will talk to your calibration software.

The other critical thing is the calibration software. You want to buy something that has a good community behind it that can help.
You have options like ChromaPure, which I’m sure people like desray can assist with or LightSpace CMS which is another option backed up by a big community to guide you through.
The idea behind this software is that they are not limiting you to only one type of monitor and they don’t require you subscription fees, unlike Portrait Display.

I don’t think I can mention other forums here, but shoot me a PM and I can provide you some links to read.

Given the help I got from desray over this forum, you’ve come to the right place. Lots of info here.

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Haha Gil, me and Pete already knew each other for a very long time…and he knew I’m into projector calibration. :stuck_out_tongue:

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