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Ursa's "Guide to Basic Display Calibration for New Users" - a MUST read!!

post #1 of 63
Thread Starter 
I ran into this gem in the main calibration FAQ, and it seemed like an incredibly overlooked wonderful piece of writing that I feel every new calibrator should read. It is such a well written and important document that I decided to start this thread not only to alert people of of its existence, but to serve as a place to ask Bill questions or for clarification of any of the information that he wrote.

Bill starts off the manual with a simple, but fairly thorough explanation of the science of color - not one of those boring texts that only an engineer could appreciate, but rather just enough to get one interested in how color works, how we see color, and how we measure it - basically he provides a foundation of knowledge on which to base your new found hobby - display calibration!

Then after setting the stage, Bill explains the basics behind display calibration - measuring and setting grayscale and gamma curves. As you probably already know, properly calibrating a display can make the difference between a mediocre picture and a fantastic one, and the importance of getting things right can not be overstated. Bill explains the measurement process, as well as providing typical examples and remedies. For all of you guys asking "How do I go beyond the simple adjustments I make using Avia/DVE, or GetGray's calibration disc?" THIS IS THE TEXT YOU HAVE BEEN LOOKING FOR!!

I have been a wannabe calibrator for some time now, and have bought some instruments to make it happen, but my only way of learning how to calibrate has come from trial and error and from pestering KRASmuzik for advice! Don't get me wrong, this manual will not make you as qualified as an ISF or otherwise experienced calibrator, but it will get you on the path.

So, hopefully with Bill's permission (I haven't asked, but since he posted the link I am taking the liberty to repost it), here is a link to the manual. Oh, and by the way, when you print it out, be smarter than I was - use a COLOR printer...the graphs will be far easier to read and comprehend.

Anyway, here's the link:

Ursa's Guide to Basic Display Calibration For New Users.pdf

I already have some questions, but I'll save them for a little later. For now I just want to make sure that everyone downloads and reads this excellent manual!
post #2 of 63
I am flattered, and a bit embarassed by Bob's lead-in. However, I will do my best to live up to that introduction. Please fire away.

The file lives in the Calibration FAQ thread here: http://www.avsforum.com/avs-vb/showthread.php?t=585527

Later,
Bill
post #3 of 63
Personally I think GetGrey and Ursa should get together and sell their freeware offerings for $50 package deal - which is about what you pay for the AVIA video that teaches you user controls.
post #4 of 63
Sell? Freeware? Nah! Though as Scott can attest, this thought did cross my mind pretty early on.
post #5 of 63
Thread Starter 
Hi Bill,

I would like to know more about your thought process as you made various changes in your H-77's RGB brightness and contrast settings. On page 17 you supplied a chart showing the changes you made from one run to the next, but I am not always clear on why you did what you did. For example, between run 2 and run 3 you made 2 changes:

lowered red brightness from 119 to 113
raised red contrast from 146 to 160

I think you were trying to get more headroom for red, right? That is, since you were running out of red at around 90%, you were lowering red brightness to bring down the overall red level, and then hoping that you could get it back in the high end. Is this what you were thinking?

My first thought would have been to lower the overall contrast to keep the 3 primaries "grouped" together in order to stop red from clipping, though I would end up with even more headroom for blue and green (which would be wasted, as I would not be using it). Would I have damaged my gamma curve by doing so? Or might that have been a reasonable course to pursue?

Even though you provided one-liners of explanantion as to the changes you made from run to run (under the RGB graphs), I did not understand why you chose to do what you did, and this is one of the more difficult concepts I am trying to grasp. I can read the charts fine, but I don't know what I should do to get RGB to track at 6500k, and eventually have white at D65. I would appreciate any insights you could provide as to why you made the choices that you did, and what it was in the charts that caused you to take that particular action.

Thanks!
post #6 of 63
Quote:
Originally Posted by Bob Sorel View Post

Hi Bill,

I would like to know more about your thought process as you made various changes in your H-77's RGB brightness and contrast settings. On page 17 you supplied a chart showing the changes you made from one run to the next, but I am not always clear on why you did what you did. For example, between run 2 and run 3 you made 2 changes:

lowered red brightness from 119 to 113
raised red contrast from 146 to 160

I think you were trying to get more headroom for red, right? That is, since you were running out of red at around 90%, you were lowering red brightness to bring down the overall red level, and then hoping that you could get it back in the high end. Is this what you were thinking?

You got it. The goal here was to try to see the relative magnitudes of changes for each control, i.e., was contrast a more granular control than brightness. The result? Not really. I still had clipping (pretty severely). Also, the end result of run 3 had my red color balance curve fairly obviously downward sloping. This indicated that I needed to further decrease brightness as well as backing down contrast. This then led to the changes I made for Run #4.

Quote:


My first thought would have been to lower the overall contrast to keep the 3 primaries "grouped" together in order to stop red from clipping, though I would end up with even more headroom for blue and green (which would be wasted, as I would not be using it). Would I have damaged my gamma curve by doing so? Or might that have been a reasonable course to pursue?

That sounds reasonable, but the question is how many tries it would have taken you to get the balance right. Since the primaries were inherently unbalanced to begin with, I did not try to maintain the ratio on the way down. Instead, my goal was to first maximize my limiting color (red), then to bring the other primaries in balance with it later.

Quote:


Even though you provided one-liners of explanantion as to the changes you made from run to run (under the RGB graphs), I did not understand why you chose to do what you did, and this is one of the more difficult concepts I am trying to grasp. I can read the charts fine, but I don't know what I should do to get RGB to track at 6500k, and eventually have white at D65. I would appreciate any insights you could provide as to why you made the choices that you did, and what it was in the charts that caused you to take that particular action.

Thanks!

The critical change was from Run #3 to Run #4. Since I had already set my master brightness and contrast, I did not want to make too radical of changes. So, Run #2 told me that I was not going to get a free lunch by tweaking a control for which I had no real documentation. Run#3 was similar, in that it showed that brightness and contrast were having about the same impact, and that I was really clipping red at that point.

The key was the downward slope in the color balance curve for red. If you think of it as a line, I needed to lower the low end a bit and bring up the top end a lot. However, since I was out of red at the top end, and needed to lower my contrast there, I needed to crash the other two primaries instead.

This may be an important point: lowering the other primaries will have a similar effect to raising a single primary (and vice-versa).

Thus, since I needed to a) lower the absolute level of red, and b) raise the relative level of red at the high end, this necessitated lowering the blue and green contrast almost as severely as I was changing red. If you look at the chart on p.17, you see that not only did I drop red contrast 16 points from my initial setting (Run #1), I also dropped blue 14 points and green 13 points. The result was reasonably flat color balance, but with red being significantly below blue and green.

At this point, I could have raised the red brightness a bit while lowering blue and green brightness, and the display should have been balanced relatively well. Of course, lowering green brightness would have probably lowered my black level beneath my ambient light floor and crushed my blacks. As a result, you see in Runs #5 - #7 my attempts to get back as much red as I could, while dialing-in the changes to blue and green to balance the primaries out.

Make sense?

Later,
Bill
post #7 of 63
Thread Starter 
Hi Bill,

Thanks for the detailed explanation! I just got back and will need to reread and study the info more to have it sink in, but I think I got the gist of it already. I'll be back with more question to torment you, I'm sure...
post #8 of 63
Bob - No problem! Aside from you and Kevin, no one seems to have read the thing, so it's not like I'm getting inundated. I will be out of pocket most of tomorrow (one last day trip before my vacation), so I can't promise anything too responsive.

Later,
Bill
post #9 of 63
I'd like to second Bob's praise of Bill's pdf - it's really nice to have this kind of detailed account of calibrating. Given all the H77/78/79s out there, word of this document should be spread although the general principles can of course be applied to other pjs.

In my experience with the H79 and the Spyder2Pro 2.0, as well as with an OpticOne previously, I've found the same kind of behavior in the upper red, and even with a new bulb (with more red overall) I had to turn down red contrast to -6 or so to correct a bit of a peak and then dropoff at 80+% stimulus and then drop blue and green to -14 for results very similar to Bill's. (These are my rough recollections of the settings I used in the Image=>Advanced Adjustment section of the regular menu.) I had to turn red brightness down somewhat, too. I got good linear results for xy, using the TV and gamma 1 settings.

I see Bill is getting into the service menu for his cuts and gains. I haven't gone into the service menu since my early days with the H79 because using controls caused highly erratic responses reminiscent of the peaky graph he presents in fig 10. Gamma controls in the sm were notorious for causing it, but I think my adjusting contrasts/brightness controls did it, too. Just beware of this if you do go into the service menu.

Dan
post #10 of 63
Bill,

I just read it. Incredible. I actually feel like I understand everything much better now, as opposed to before reading it. You did a bang-up job writing that. I couldn't have asked for something more easy to follow.

Having read it, I have a question back regarding Run 4, and a possible fork in the road that could have been used. It seemed that blue and green both tracked pretty close to one another, although being 10-20% oversaturated, but fairly flat across the stimulus range. Red, on the other hand seemed to be about 25-30% undersaturated. The one thing I did notice was that it was fairly flat compared to other readings. Aside from needing to address the overall oversaturation of blue and green, would this have been a good place to try and boost the red saturation with the use of a CCR filter? It would seem that this might make things track better (flatter) and bring the stimulus of the three primaries to within closer values of one another.

I would really like to pick up a SpyderTV or other device. I understand that the GMB Eye One is supposed to be even better, but the price is quite a bit higher as well. Looks like I'll have to save some pennies and get at least something so that I can tinker and learn some more.
post #11 of 63
Quote:
Originally Posted by Ten 99 View Post

Having read it, I have a question back regarding Run 4, and a possible fork in the road that could have been used. It seemed that blue and green both tracked pretty close to one another, although being 10-20% oversaturated, but fairly flat across the stimulus range. Red, on the other hand seemed to be about 25-30% undersaturated. The one thing I did notice was that it was fairly flat compared to other readings. Aside from needing to address the overall oversaturation of blue and green, would this have been a good place to try and boost the red saturation with the use of a CCR filter? It would seem that this might make things track better (flatter) and bring the stimulus of the three primaries to within closer values of one another.

Careful on using "saturation" to describe these characteristics!

As for the CC filter, you could do it, but it would have led to about 1400:1 CR (the red level was at 74.6% and green was at 106.3%. Thus, the filter would need to have cut green by 30% to bring it level with red). I am currently sitting at about 1800:1, so as I indicated above, my goal after Run 4 was to get back as much of the CR as I could. In this case, it was without resorting to filters.

Quote:


I would really like to pick up a SpyderTV or other device. I understand that the GMB Eye One is supposed to be even better, but the price is quite a bit higher as well. Looks like I'll have to save some pennies and get at least something so that I can tinker and learn some more.

Jeff will probably disagree with me, but in so long as your expectations are set appropriately ahead of time, that would be a good approach in my book!

Later,
Bill
post #12 of 63
Thread Starter 
Ok, let me take two problems at a time:

Quote:


Since the primaries were inherently unbalanced to begin with, I did not try to maintain the ratio on the way down.

1. Ok, Bill, here is one area (of many ) in which I am confused. If I am reading your manual correctly, I would assume that the lower graph in figure 7 represents your initial readings (pre calibration). As such, it looks to me as if blue and green are tracking very closely, and red is the only "problem" that needs fixing. Have I got the wrong graph for your precalibration data, or am I misinterpreting it? (Recommendation: Since you have 7 runs listed in the chart in figure 8, it would make things much easier to follow if you had figure 12 containing all 7 corresponding graphs so that dummies like me can relate the graphs to the chart more readily.)

2. I am further confused by the figure 12, run 3 graph. Again, if I am reading correctly (and I probably am not) the only changes you made between run 1 and run 3 were to red, raising the red contrast from 146 to 160, while at the same time dropping red brightness from 119 to 113. By my way of thinking, the only color that should been affected is red, yet blue is tracking around 60% in the run 3 graph. WTF? Why did blue tracking drop so drastically when you didn't change any of its levels? And why didn't the red levels change much, if at all?
post #13 of 63
Quote:
Originally Posted by Bob Sorel View Post

1. Ok, Bill, here is one area (of many ) in which I am confused. If I am reading your manual correctly, I would assume that the lower graph in figure 7 represents your initial readings (pre calibration). As such, it looks to me as if blue and green are tracking very closely, and red is the only "problem" that needs fixing. Have I got the wrong graph for your precalibration data, or am I misinterpreting it? (Recommendation: Since you have 7 runs listed in the chart in figure 8, it would make things much easier to follow if you had figure 12 containing all 7 corresponding graphs so that dummies like me can relate the graphs to the chart more readily.)

Figure 7 is my "base" reading, and if you want something really messed up, how blue "came up" relative to red and green from run 3 to 4, as well. I really have no explanation for why that happened. It could have been residual issues from mucking around with the DLP contrast and brightness, or it sould have been a measurement anomaly. Since I was focusing on getting red "flat", I was not too concerned about blue and green through run #3. (see below)

As for why I put figure 12 where it was: I wanted it to be all on one page, and that was the first place I could put a page break that did not destroy the flow or leave large amounts of white space. I'll try to get it closer to the measurement table in a future update. Great feedback, btw!

Quote:


2. I am further confused by the figure 12, run 3 graph. Again, if I am reading correctly (and I probably am not) the only changes you made between run 1 and run 3 were to red, raising the red contrast from 146 to 160, while at the same time dropping red brightness from 119 to 113. By my way of thinking, the only color that should been affected is red, yet blue is tracking around 60% in the run 3 graph. WTF? Why did blue tracking drop so drastically when you didn't change any of its levels? And why didn't the red levels change much, if at all?

First, remember that the RGB levels are all relative. However, your guess is as good as mine as to why that happened. I had just mucked with some controls which I really should not have, and I did not know what to expect after that.

Do any real experts have any ideas?

Later,
Bill
post #14 of 63
Thread Starter 
Quote:


Figure 7 is my "base" reading, and if you want something really messed up, how blue "came up" relative to red and green from run 3 to 4, as well.

Yeah, I noticed that too, but I am just trying to sort out one unexplained reading at a time... You lowered red, green and blue contrast, yet blue came back up relative to green?

Quote:


I really have no explanation for why that happened. It could have been residual issues from mucking around with the DLP contrast and brightness, or it sould have been a measurement anomaly.

This is one of the things that is driving me batty about calibration - unexplained phenomena. I have had similar experiences playing around with my EyeOne, and thankfully Kevin has been around to figure out what I'm doing wrong! But if I'm going to truly get a grasp on calibration, I need to understand why things like the blue level drop and subsequent return happened, going against expected results. Is calibration truly just a "take a wild guess and hope for the best" kind of procedure? There has got to be reasonable explanation for the sudden large shifts in blue level.
post #15 of 63
Think of your RGB% chart as a see-saw - but with three seats instead of two.......
post #16 of 63
Hey guys. something i just noticed while reading thru the calibration guide. am i supposed to adjust color & tint before doing a full grayscale, gamma calibration? i adjusted my master brightness & contrast controls in the user menu first, but i'm not 100% sure about whether i'm supposed adjust master color & tint before grayscale/gamma.

thanks guys.
Carmine.
post #17 of 63
color & tint has no impact on greyscale.
post #18 of 63
Quote:
Originally Posted by Ursa View Post

Bob - No problem! Aside from you and Kevin, no one seems to have read the thing, so it's not like I'm getting inundated. I will be out of pocket most of tomorrow (one last day trip before my vacation), so I can't promise anything too responsive.

Later,
Bill

Don't be too sure they're the only ones reading it. I found it to be incredibly informative, though I'm a novice at best so just learning and learning some more.
post #19 of 63
I just read Ursa's guide and I must say it is very informative, great work Ursa. I picked up on a lot of information that made me understand things instead of just accepting them and not knowing why they are the way they are. Keep up the good work!!
post #20 of 63
Quote:
Originally Posted by krasmuzik View Post

Personally I think GetGrey and Ursa should get together and sell their freeware offerings for $50 package deal - which is about what you pay for the AVIA video that teaches you user controls.

I would be more than happy to put it on the disc with Bill's permission. I'm trying to wrap that little snowball up over the holidays. Then maybe attempt a PAL version (I never learn ).
post #21 of 63
Quote:
Originally Posted by GetGray View Post

I would be more than happy to put it on the disc with Bill's permission. I'm trying to wrap that little snowball up over the holidays. Then maybe attempt a PAL version (I never learn ).

Scott - A fellow Houstonian AVSer, Tom Green, was nice enough to edit a slightly different version for me, so if you can give me a bit of time, I'd like to get a new revision out. We should take that discussion offline, though.

Later,
Bill
post #22 of 63
Understood. That would be awesome if it works out.
post #23 of 63
First, I want to say thank you so much for this manual. I know the amount of time it involves, I wrote one a few years back for the Sony 12xx projectors and it was a shwack of work.

I've just retubed my Ehome 8500 and am just starting to read you guide in preparation for calibrating it.

Again, thanks!

Wes
post #24 of 63
Wow. I've had only a couple of minutes to briefly skim the pdf, and already I can see that what little theory I thought I understood about calibration needs to be unlearned. Thank you so much for creating this document; it's a godsend.
post #25 of 63
Thanks! Bob's already asked a few questions, so if anything is unclear or confusing, please ask. I'd like to use this thread to help make the subsequent revisions (no promise on timeline) better.

Later,
Bill
post #26 of 63
Thread Starter 
As Bill has mentioned, I had a few questions, and then I have been continuing with him offline (don't ask me why - I have no idea ), but since it would probably be of use to others, I asked Bill's permission to reprint it here:

It started off with:

Quote:
Originally Posted by Bob Sorel View Post

Hi Bill!

After reading this I figured that I would add my 2 cents worth, since it looks like you will be editing your manual:

Quote:


Scott - A fellow Houstonian AVSer, Tom Green, was nice enough to edit a slightly different version for me, so if you can give me a bit of time, I'd like to get a new revision out. We should take that discussion offline, though.

As far as I am concerned, the sample calibration of your H-77 is the "meat and potatoes" of the entire manual. I have read quite a bit on calibration, but no one ever seems to take the initiative to actually run through an example to show a new user what controls to adjust and how much to adjust them. I know that it will be different with each display, but it is just soooo nice to see someone show some real numbers and graphs to illustrate the point. That being said, I have a few constructive suggestions:

1. Spend even more time with your sample calibration. You are one of the first writers to finally give an example...please make the most of it and go into further detail in regard to your thought process. Explain why you did what you did...explain what you were hoping to achieve...explain where you failed as well as where you succeeded. In general, I would like to see much more time dedicated to a runthrough process. I gained more "hands on" knowledge that way than from all of the theory combined.
2. Please let us know when you saw unexplained phenomena. You have no idea how long I scratched my head over the blue shift during your runs. It just didn't make any sense at all based on the changes that you were making, but I figured that I must be missing something in my understanding. If you had let us know that the blue level shifting around was as much a mystery to you as it was to me, then at least I wouldn't have spent so much time trying to understand what I had missed. Does this make sense?
3. Explain the goal of the calibration process in terms of the software graphs and charts. I would assume that we are trying to get three basic things adjusted as well as possible:
___1. White to be "on target" at D65 on the CIE 1931 chart (or should we use the CIE 1976(?) chart?
___2. For all three primaries to track 6500k as closely as possible from 0% to 100% stimulus.
___3. To have the gamma curve track a perfect 2.22 gamma curve as closely as possible.
Are these assumptions correct? If not, what are the correct goals? If we are forced to make sacrifices, where are the most and least desirable places to make reconciliations?

I hope I am not coming off as negative or complaining - I think that your manual is the best piece of writing on the subject that I have found! I just offer myself as the litmus test for the worst case dummy that is likely to read your text, so if I can understand it, than anyone can, and writing for the lowest common denominator will insure that as many people as possible are able to benefit from your hard work.

Thanks for listening and keep up the good work!

And then Bill sent me this reply:
Quote:


Bob - thanks for the feedback and the support. I'll definitely try to incorporate this into a future revision, though I'm not sure that I can do it soon.

As to your goals, below: I agree with #1 (grayscale should track D65 throughout). This implies a balance in the primaries, so the intent of #2 is covered in #1 if I am imputing your meaning correctly.

I would re-word #2 to say that the primaries and secondaries produce lifelike skin tones (reds) and that there is good separation of greens and yellows (the H7x are particularly bad about this out of the box).

I am not so sure about #3. If you follow the defined curve strictly, you only end up with ~1000:1 contrast between just above black (17) and reference white (235). This seems like a big damn waste of contrast to me. However, I am not sure what it should come out to be. I do know that people seem to commit all sorts of algebraic and statistical brain farts when calculating gamma, so there has to be some big epiphany that I have just completely missed somewhere along the way.

Your thoughts?

Which continued with:
Quote:


The only thoughts that I have are in regard to 2 areas:

1. Gamma - I just assumed that 2.22 was the "perfect" gamma curve, but I sure am willing to experiment with different gammas to find out which one(s) work best for a particular projector/screen/environment combination. Most of the curves I settle on are a bit higher - more like around 2.39 to about 2.65 ish.
2. RGB tracking - I probably don't understand how this works, but I thought that D65 could be achieved by an almost infinite combination of RGB levels, but in a perfect world they would be balanced at 100% each. In other words, D65 might also exist with a balance like this:

Red - 120%
Blue - 80%
Green 80%

(I'm just making up the numbers), but because of the imbalance of Red as compared to Blue and Green, color reproduction in general would not be optimal. Is my theory correct in that

a. D65 can in fact be achieved with many different balances of R, G, and B?
b. If "a" is correct, then would one strive to get as close to 100% for all 3 primaries for the "best" (most accurate) color reproduction?

And that brings us up to date.
post #27 of 63
Alright, now that we are out in the open, I'll defer the discussion of Gamma for a bit to tackle RGB balance and white points.

Picture, if you will, the CIE 1931 Gamut chart. For each standard, there is a defined location for each of the three primaries. However, for all current video standards, the same white point is used (D65, or x=0.313, y=0.329). Since the 1931 Cartesian system does not include luminance (Y), all points in the grayscale should hit D65. After all, since the difference between black and white is the amount (intensity) of light, the "color" of each point in the grayscale does not really change.

Let's emphasize the key point here: all points on the grayscale should be on D65.

Think of intensity, or luminance, as being orthogonal to the xy plane.

With me so far? Alright, then there is one additional piece to the puzzle: not only does each standard have a different defined point for their primaries, but they also have a different balance to the primaries that constitute white light. This is why you just can't calibrate to one standard and think it will work for all standards. Of course, for display manufacturers, this also drives you nuts because at a fundamental level, the color of a primary is going to be relatively fixed (e.g., dichroic filters, phosphor, etc. all have one color!).

So, where does that leave us for color balance? There are two issues at play here. The first is that there is a relative mix of red, green and blue that should be maintained. Second, this mix should be maintained as close to the defined white point as possible. Unfortunately, because of the pre-defined color issue mentioned above, you often cannot satisfy both of these two goals at the same time.

So, the color balance charts in my guide refer to the relative levels of red, green and blue that are required to bring the colors into balance given the defined mix for the HD standard (Green: 71.5%, Red: 21.3%, Blue: 7.2%). Why don't I look at my absolute deviation, rather than this relative deviation? Because to me, it is more important that the colors are balanced, than that they are at the right white point. Also, I can use both the color temperature and color error to tell me how far off of D65 I am, and how noticeable it will be.

Submariners have an expression about driving a sub. Bad sub drivers "chase the bubble", and as a result, they are always putting in steering corrections based on where the instruments said you were, rather than based on where they are indicating you are going. For me, focusing on the absolute deviation is a lot like chasing the bubble. Algae in Theodin's beard bugged the snot out of me. Slightly blue snow does not.

So, back to Bob's original question: are there several mixes of RGB that will meet D65 and be properly balanced for a given standard? The specific answer is no. However, the nuanced answer is that there is an error tolerance around this (dE), and I aim to make sure the balance is correct more so than hitting the theoretical level for a primary to be at D65.

Now if that is perfectly clear, then I definitely need to pay for the second course of Alan Greenspan's Guide to Business Communications!

Later,
Bill
post #28 of 63
Drapp, can you post your final setting for your h79 after calibration?
post #29 of 63
Jim, I could do that although the settings wouldn't necessarily be applicable to your situation. The general pattern that has cropped up with the H7* series is described well in the following link:

http://www.hometheaterhifi.com/volum...05-part-2.html

The main issues that seem to be pretty consistent with the H7* pjs are excessive red in lower IREs that is relatively easy to correct, and the drop in red at higher IRE that is less easy to correct without overall loss in contrast due to the necessary accompanying drop in green and blue to bring one back to D65. In my early calibration runs I'd create a red bump around 80 IRE that came when trying to turn up red to compensate for the 100 IRE fall-off; plus, red clips overall when turning it up too much. Steve Smallcombe used a red filter to correct the upper IRE red falloff, but lost 35% brightness and had to then use the brightmode to compensate. This approach maintains contrast.

With my new bulb I've used compromise settings in which I've turned down red until the fall-off is less severe at higher IREs, then turned down blue and green further, so my settings are something like R contrast - 6, B contrast -13 and G contrast -14, with TV and gamma 1. My regular contrast may be around 4 and and brightness 1-2, but this is from memory (I'm not home right now.) I have a High Power screen so I don't perceive a brightness problem now. I might try a CC10R and do a re-calibration, turning up my B and G contrasts to regain some overall contrast/dynamic range.

Dan
post #30 of 63
Ursa,

What a great job....this should be a sticky!!! How do you make that happen??

Larry
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