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I recently attended the THX Video "System" Calibration course held in Las Vegas. In light of some recent posts regarding this course, I felt I owed it to Gregg and Michael to throw in my impression of the course. It was worth every penny. While I don't consider myself to be a "seasoned" vet, I don't consider myself new to the neighborhood either, I still learned a tremendous amount of material. Gregg and Michael literally held your hand through the entire process, and explained everything you needed to know about calibrating the entire video chain in depth. The lab setup was excellent with panels and projectors from some of the "top" manufacturers, and the amount of equipment used to calibrate was well represented. We had opportunities to play with Runco panels and projectors, Pioneer Elite, NEC, Epson, Marantz PJ, Samsung LCD and RPTV DLP, LG and the Lumagen Radiance using Photo Research Spectro, Minolta CS200, Klein K10, i1 Pro, OTC1000, Chroma 5 and puck 5, Colorfacts, CalMan, Accupel and Sencore CP6000/403 gear. No other place will you get to play with such equipment in a controlled environment, and with the knowledge base represented in that room and for a period of three days. Bottom line is, I can't say how happy I am with the result. A special thank you to Gregg and Michael. I highly recommend taking the course.


PS...there was about an hour worth of gamma material if not more.
 

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So what's the deal with gamma?


After all I've read it seems that camera gamma with a 1.1->1.2 power function applied after you apply the inverse formula of what was used to encode the material "should" be the right settings for rec.709. The leway between 1.1 and 1.2 is there for different viewing enviroments.


Since we don't usually have as much control I'd guess we shoot for a straight power function of around 2.35 or so for light controlled down to 2.2 for daylight living room.


Anyway, I'm sure alot of the talk was about how it's encoded, what it acutally is and means for the viewing enviroment and how it ends up not being one thing or number and not a specific answer to the question (otherwise it would be posted long ago).
 

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This thread was not intended to be a Q&A thread, but merely to point out that the course is well worth the time and money. I am sure if Michael or Gregg wished to reveal the content of the course, they would have done so already. If you want to know, attend. I highly recommend it.
 

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while I appreciate the public endorsement of the service, this isn't really a forum for professional calibrators.


As rank amateurs we like to share what we know. So it isn't really very polite to come in here saying, "I just got two hours of professional training on what to do about gamma and I'm not going to share a lick of it with you, because you didn't pay."


I'm not asking you to post the course notes or doing anything unethical, but if you don't intend to discuss what you learn, you really shouldn't bring it up in an information sharing forum at all.
 

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^^^^^


Thank you!
That is precisely what the comment was about. And Sotti, if you want an answer, I think you are focusing a little too much on the gamma issue. Precision is impossible from unit to unit on something that is not built to military specs. One set might be 2.2, the same model might be 2.5. You never know until you take the measurements.
 

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It could also be noted that formal class time runs basically from 9:00 AM to 6:00 PM, but the instructors offer an additional two hours in the morning, plus two or more hours after a supper break for students who want to work more on the displays. Gregg and/or Michael are in the room to oversee and help with questions during those times.


Some forum members have expressed a desire in the past to go along with an experienced calibrator on jobs for the learning. This THX class is an opportunity akin to such an experience. A more disciplined and energetic student could theoretically be in the class room, working on equipment, for as much as eight or nine hours additional to the course material.


Many of the classes also include the presence of fellow students who are imaging industry professionals. These individuals are usually quite willing to share insights and experiences from a professional perspective that augment the curriculum. Examples have included representatives from calibration instrument manufacturers, program production technicians, display manufacturer representatives, etc.


Best regards and beautiful pictures,

G. Alan Brown, President

CinemaQuest, Inc.

A Lion AV Consultants Affiliate


"Advancing the art and science of electronic imaging"
 

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Greetings


It should be noted ... again ... that the class is a living document. It changes with every class. The material is always evolving as we find out new things.


For instance, the next class is going to be different again because I am expanding the CMS section of the slides. The anamorphic lens part will be trimmed too.


As for gamma, the main take home for the students is that once you are close ... people should not obsess over it too much because improvements beyond that generally really really hard to see on real life material. There are bigger fish to fry.


The class is not about anally tweaking things to the "n"th degree.


The class is not just for professionals. It is for any and everyone. We've had enthusiasts come through this thing too. It's just a class.


The professional part comes in if you start to charge $$ for the work.


Regards
 

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Quote:
Originally Posted by SierraMikeBravo /forum/post/15569753


^^^^^


Thank you!
That is precisely what the comment was about. And Sotti, if you want an answer, I think you are focusing a little too much on the gamma issue. Precision is impossible from unit to unit on something that is not built to military specs. One set might be 2.2, the same model might be 2.5. You never know until you take the measurements.

Well the only reason I was focusing so much on gamma was I wrote an app that lets me modify the LUT of my video card directly. So I can tune the output step of my video card to have fine control over the end to end gamma of my system.


Of course if you are going to minutely tweak something to match, gotta know what you are trying to match. So is it the goal to have your display use a pure power function with an exponent from 2.2-2.5 based on display quality/lighting enviroment or is it correct to use camera gamma with a power exponent of 1.1-1.2 added afterwards. Since using camera gamma give a true end to end gamma of 1 for rec.709 material I was thinking that this coupled with a 1.1-1.2 power function could yeild the true target.


But then again if everyone has displays and nearly all displays have simple power function like responses maybe it's best to simply mirror the majority but with near perfect response.


Anyway I've played with it a bunch, it's one component, but it probably has more varried and conflicting ideas than any other topic on this board. (Debating what rec.709 red is doesn't make for a good debate).
 

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One factor that I haven't read mentioned is, What is the gamma response of the monitors in the mastering houses? I know this varies from studio to studio, so as Michael stated, get close. There is no one right answer.

Yes, there is standards and science involved, but when the studios aren't strictly adhering to it, why should you.

This is where some of the art of calibration comes into play.


Back on topic, as a seasoned calibrator, I attended the THX class late last year and found it very informative. Working alongside fellow professionals and exhanging tips and techniques proved very useful to me. As display technologies evolve the learning process never stops. Kudos to Michael and Gregg for making the THX class an always adapting training course.
 

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would I be completely lost if I came in to this class with little or no calibration experience? I understand the basics of the basic controls (brightness, contrast, color, tint..) and have used set up discs, but have zero experience with professional calibration equipment. Would I be alright in this class, or is it more geared toward people with prior experience?
 

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I recommend that you consider taking the ISF course first (after studying this publication: http://www.cinemaquestinc.com/isf-mag.htm , and all the sticky threads above). Then start studying more on your own (especially being a part of the ISF Library Forum- restricted to ISF grads who actually calibrate displays), plus start using some good basic gear (EyeOne Pro & CalMan) on TVs/computer monitors/projectors owned by yourself and friends/relatives, etc. After six months or more, consider taking the THX course. Both courses cover a lot of gound very quickly. If you don't have much of a foundational concept of imaging science and display standards, you're likely to get lost and not realize the full benefit from the little time in these courses. Preparation is the key to getting your money's worth from any formal training. It also is important to be ready to use the information regularly after the coursework.
 

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Greetings


We have been tracking the students that attend the class and so far, most have been through ISF prior to taking the class. Does that make the ISF a pre-requisite for this class? No, not at all.


We also kept our eyes on those that have not been through the ISF before just to see how they were keeping up with the class.


The only real pre-requisite is that the person attending needs to be an enthusiast first. If they have dabbled in the various test discs like AVIA, DVE and so forth ... then they are well equipped to tackle the class.


One recipe for failure here is if you are not an enthusiast to start with. You cannot be selling real estate one week and then decide to come tackle this the next. Pretty much means the material will overwhelm you ... (Although I still maintain that this stuff ain't rocket science.) It has happened to one student, but he was in over his head ... and he took the ISF too. (He was not an enthusiast at all and signed up for the class for the wrong reasons.)


Many who have been through the official ISF class tell us that they leave that class with deer in headlights looks on their face. Too much theory ... little hands on. The nature of a two day course. The theory is needed ... but leaves little time for application of the theory. ISF attendees tend to really learn the calibration business themselves ... once the class is done. They have to teach themselves how to be calibrators.


The THX class teaches people how to calibrate TVs. You get the theory ... and you get the hands on under supervised conditions. Supervision means that beginner mistakes are minimized since they are caught early on before they perpetuate themselves into bad habits. Students get slapped down right away.


Conversely, if you have to be teaching yourself how to actually calibrate a TV ... one might make a whole bunch of mistakes simply due to misunderstanding of the class material. No supervision means no one catches the mistakes at all and they carry forward into the calibration business and eventually become habits that might be hard to break.


The class is promoted as being generally devoid of technobabble. All the big concepts are presented in easy to understand bite size pieces. Why? Because the students are expected to relay this same information to their clients as part of the education process.


Regards
 
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