TITAN REFERENCE - With filter and S shaped Gamma LOOKING GREAT. - AVS Forum
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post #1 of 38 Old 08-28-2008, 06:02 PM - Thread Starter
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As mentioned early we received a Titan Reference in the Lab with a Supernova 80/85 (.8 gain even luminosity wide angle gray screen) 12 foot wide .

Our first impressions were unfavorable about the screen since it is a gray screen and the screen rejects ambient light only in the vertical direction which DNP should have clearly let us know would be the case. DNP is definitely not in the same class as Stewart or even SMX from a customer service standpoint.

That being said it's A REALLY IMPRESSIVE 85 DEGREE HALF ANGLE VIEW FROM THE TOILET on a bathroom to the left of front wall. The screen does help ansi reflection reduction and after calibration and s-gamma implementation we have decided not to return it back to the manufacturer.

In my initial impressions I had expressed noticing a huge gap between this projector and the modded Barco's. As reported I was not getting that 70 mm look that captivates everyone that sees these superkontrast units. Ok now here I am going to retract that statement (or qualify it at least).

We loaded an S shape gamma (based on a 2.2) and voila DEPTH OUT OF THE WAZOO. Now we have that lovely 70mm depth. Sure the dmd's in the consumer units are a trifle noisier, the pixel density a little less, more grit and haze, the color (despite a super effective xenon mode that uses a filter to simulate a TIP7 color calibrated DCI unit- SIM2 owners eat your heart out)the color is still not the same as one of those explosive xenon 2kw, but darn what a difference a gamma curve makes. No longer it seems like a projector from 2008, at least now it looks like 2010 technology.

I can now recommend this projector as the creme de la creme of UHP projectors, with 6,260 seq cont and 3,100 ansi lumens it is the UHP refrence projector with which to compare all other uhp projectors next week. So guys do stop by the Digital Projection Booth and check it out.





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post #2 of 38 Old 08-28-2008, 08:25 PM
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Could be my PC display or your camera, but where is the shadow detail? The propeller and windows look like a cartoon.
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post #3 of 38 Old 08-28-2008, 09:03 PM
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Peter lookin good. Does the projector offer on board gamma or are you using an outboard video processor to adjust the S curve. I think D cinema spec calls for an S curve does it not.
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post #4 of 38 Old 08-28-2008, 09:18 PM - Thread Starter
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I am a lousy photographer and the camera is a 300 camera so don't expect any miracles. When I resize the image down you loose a lot of quality.

Thanks Alan, dpi has software where you can set up custom LUT and then loaded via ethernet.

Yes I use a DCI gamma S curve . The depth of field is phenomenal.
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post #5 of 38 Old 08-28-2008, 10:52 PM
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Cool. Im hearing good things about the Titan Reference. I had a look at the Titan 250 when it came out and it was a turd. Someone here described it as "a glorified data machine". I will certainly need to have a look at what this and anything new from DPI.

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post #6 of 38 Old 08-28-2008, 11:10 PM - Thread Starter
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I bet you that they will be adding servo lens to this unit. As it ships you can change aspect ration just with zoom and shift (no focus touch up necessary)

You can see the blues are terrific very film like (based on the dci machine tip7 rec 709 d65 color I am now fond of)













A little green...




Blackness of space











And MALPASO red...





What a difference the gamma makes, amazing.
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post #7 of 38 Old 08-29-2008, 12:59 AM
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Quote:
Originally Posted by CINERAMAX View Post

We loaded an S shape gamma (based on a 2.2) and voila DEPTH OUT OF THE WAZOO.

It isn't my goal to rain on your parade, but I think what you found is more proof of why high on/off CR matters, and looks to me like you basically robbed Peter to pay Paul. That is, you had a certain amount to spend between 0 IRE and 100 IRE (like 6000:1 on/off CR) and decided to spend it in the mid-range. I would like to see the gamma curve to see where the bends are. If you are running Blu-ray, DVD, or other consumer sources like that, then they weren't mastered for S-shaped gamma curves. But you can use one and make many images look better and have more depth, because those images would now have more CR. But, it would steal CR from some other images. Kind of like SOWK finding that going to a high gamma number with his Marantz 11S2 added a lot of depth to many brighter mixed images, but then made many dark images look worse than a 2.2 gamma. With the S-shaped curve, somewhat similar to spending the vast majority of $6k between 10 IRE and 90 IRE, but then not having much left over for CRs between things outside that range.

Picture the curve that was used to master the material on a CRT monitor. There is some debate amongst experts, but it would be in the range of a 2.2 to 2.5 gamma. Charles Poynton told a friend of mine around 2.4 or 2.45 (I don't remember which). Now if you take that gamma curve and pull 10 IRE down toward 0 IRE and 90 IRE up toward 100 IRE you will end up with less CR in images with 10 IRE and under or with 90 IRE and up. So, less shadow detail and less highlight detail. I wouldn't expect good things overall in dark images. Say the 2nd half of chapter 7 of the 2nd Alien vs Predator movie. The black level is already raised from having 6k:1 on/off CR or less and now the 10 IRE level has been lowered even more by using an S-shaped gamma curve and borrowing from down there, crushing the range between 0 IRE and 10 IRE. Or maybe it was things under 20 IRE or 30 IRE where CR was borrowed from. Either way, it has to be borrowed from someplace for you to apply it elsewhere in the video encoding range.

I'm guessing you'll argue against this, but please try it if you can. Find some of those dark images like I just mentioned and try them with a 2.2, a 2.4, and your S-shaped gamma curve.

If you had tons of on/off CR you could still have the CR you want between 90 IRE and 10 IRE (or 70 IRE and 30 IRE) and still have a lot left over to use between 0 IRE and 10 IRE (or 0 IRE and 30 IRE). I know you told me recently that I would find that on/off CR was unimportant once it got over the 3500:1 range, but I think you should see why it still matters by the tests you are running and by then looking at some dark images where everything is under 10 IRE (but not just a blackout) and see what is going on down there. If you want the depth you are seeing with your S-shaped curve and also want the dark images to look as good as possible, you should want much higher on/off CRs so that you can have that CR in the mid-range and also at the low end.

As an example, I would expect Wormtongue to look more like a head on a black hole in the scene I described in the More Test Scenes section here:

http://www.hometheaterhifi.com/volum...06-part-5.html

by going to an S-shaped gamma curve compared to the numbered gamma curve it is based on. Although I would like to see the 2 curves together to see where the deviations were made.

--Darin

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post #8 of 38 Old 08-29-2008, 03:35 AM
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The S shaped curves are good, but they are only truly great when the content is full DCI. The difference compared to BD is very readily apparent.

Content adaptive curves will also be available before too long, both by media embedded preset curves and by image analysis.

The fact that these tables will be even better with high CR machines is something I feel we will see at some point in the not too distant future.



Peter, I too am a fan of P7 calibrated ,Rec 709 D65 color, but you don't need a DCI machine to get it.

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post #9 of 38 Old 08-29-2008, 06:37 AM
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Nice pics Peter. Nice to see that you could have seen some bad UHPs and perhaps had written them off prematurely.

Thanks Darin for the nice explanation of gamma curves effects.

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post #10 of 38 Old 08-29-2008, 08:45 AM
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Quote:
Originally Posted by coldmachine View Post

The S shaped curves are good, but they are only truly great when the content is full DCI.

And why is that? >=10 bit source?
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post #11 of 38 Old 08-29-2008, 09:00 AM - Thread Starter
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Not really cause it is encode decode so it is more effective. Nonetheless it has been my secret weapon to make Blue Rays look like 70mm and now gives hope that the 70mm look can be achieved with UHP. Depth being the trickery factor as I found out last night.
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post #12 of 38 Old 08-29-2008, 09:45 AM - Thread Starter
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Quote:
Originally Posted by darinp2 View Post

It isn't my goal to rain on your parade, but I think what you found is more proof of why high on/off CR matters, and looks to me like you basically robbed Peter to pay Paul. That is, you had a certain amount to spend between 0 IRE and 100 IRE (like 6000:1 on/off CR) and decided to spend it in the mid-range. I would like to see the gamma curve to see where the bends are. If you are running Blu-ray, DVD, or other consumer sources like that, then they weren't mastered for S-shaped gamma curves. But you can use one and make many images look better and have more depth, because those images would now have more CR. But, it would steal CR from some other images. Kind of like SOWK finding that going to a high gamma number with his Marantz 11S2 added a lot of depth to many brighter mixed images, but then made many dark images look worse than a 2.2 gamma. With the S-shaped curve, somewhat similar to spending the vast majority of $6k between 10 IRE and 90 IRE, but then not having much left over for CRs between things outside that range.

Picture the curve that was used to master the material on a CRT monitor. There is some debate amongst experts, but it would be in the range of a 2.2 to 2.5 gamma. Charles Poynton told a friend of mine around 2.4 or 2.45 (I don't remember which). Now if you take that gamma curve and pull 10 IRE down toward 0 IRE and 90 IRE up toward 100 IRE you will end up with less CR in images with 10 IRE and under or with 90 IRE and up. So, less shadow detail and less highlight detail. I wouldn't expect good things overall in dark images. Say the 2nd half of chapter 7 of the 2nd Alien vs Predator movie. The black level is already raised from having 6k:1 on/off CR or less and now the 10 IRE level has been lowered even more by using an S-shaped gamma curve and borrowing from down there, crushing the range between 0 IRE and 10 IRE. Or maybe it was things under 20 IRE or 30 IRE where CR was borrowed from. Either way, it has to be borrowed from someplace for you to apply it elsewhere in the video encoding range.

I'm guessing you'll argue against this, but please try it if you can. Find some of those dark images like I just mentioned and try them with a 2.2, a 2.4, and your S-shaped gamma curve.

If you had tons of on/off CR you could still have the CR you want between 90 IRE and 10 IRE (or 70 IRE and 30 IRE) and still have a lot left over to use between 0 IRE and 10 IRE (or 0 IRE and 30 IRE). I know you told me recently that I would find that on/off CR was unimportant once it got over the 3500:1 range, but I think you should see why it still matters by the tests you are running and by then looking at some dark images where everything is under 10 IRE (but not just a blackout) and see what is going on down there. If you want the depth you are seeing with your S-shaped curve and also want the dark images to look as good as possible, you should want much higher on/off CRs so that you can have that CR in the mid-range and also at the low end.

As an example, I would expect Wormtongue to look more like a head on a black hole in the scene I described in the More Test Scenes section here:

http://www.hometheaterhifi.com/volum...06-part-5.html

by going to an S-shaped gamma curve compared to the numbered gamma curve it is based on. Although I would like to see the 2 curves together to see where the deviations were made.

--Darin

I am not married to 3,500 on off, obviously I want it as high as it can be increased while maintaining all the other important parameters. It has to look like a miniature 70mm to me first and foremost. The rest of the gravy is all welcomed.

I cannot show you the curve bending points as it was lent to me for testing purposes. If you have read Dave Richards Christie paper, that's the one but applied to 2.2 and not 2.3. Some Digital Cinema clients pay good money to the holders of this IP.

I do have that dark AVPR scene you suggested and will try to photograph your suggested little degustation of gamma flavors, fair enough? Later.
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post #13 of 38 Old 08-29-2008, 05:59 PM
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Quote:
Originally Posted by coldmachine View Post

The S shaped curves are good, but they are only truly great when the content is full DCI.

Why bother with S-shaped curves at all? According to the DCI spec, DCI projectors are supposed to use a power function with a 2.6 gamma, which is definitely not S-shaped.
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post #14 of 38 Old 08-30-2008, 01:44 AM
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Quote:
Originally Posted by Erik Garci View Post

Why bother with S-shaped curves at all? According to the DCI spec, DCI projectors are supposed to use a power function with a 2.6 gamma, which is definitely not S-shaped.


De-focus presets aren't in the DCI spec either, but are frequently used in some situations and are almost always used with certain projectors.

People chose them simply because they can offer a better viewing experience. As Peter said, people pay good money for it. Ive seem material that benefited and some that didn't.

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post #15 of 38 Old 08-30-2008, 06:03 AM
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Peter. You fox. Use of the word degustation before CM tossed it out. Classic. Maybe expensive front projectors will come with a degustation menu. If not, you can take the client out after installation to enjoy one.

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post #16 of 38 Old 08-30-2008, 07:47 AM
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Quote:
Originally Posted by coldmachine View Post

People chose them simply because they can offer a better viewing experience.

OK, it can be better for some people, but my main point is that an S-shaped curve is not accurate to the DCI spec, to address comments such as the following...
Quote:
Originally Posted by Alan Gouger View Post

I think D cinema spec calls for an S curve does it not.

Quote:
Originally Posted by CINERAMAX View Post

Yes I use a DCI gamma S curve .

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post #17 of 38 Old 08-30-2008, 08:36 AM
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If Im not mistaken DCI content is mastered to meet a certain gamma curve which the DCI projectors have built in. This is some sort of s curve.
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post #18 of 38 Old 08-30-2008, 08:52 AM
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Quote:
Originally Posted by Alan Gouger View Post

If Im not mistaken DCI content is mastered to meet a certain gamma curve which the DCI projectors have built in. This is some sort of s curve.

The standard curve is a conventional 2.6 gamma curve and the instructions for the projector to use this is part of the PCF (projector configuration file) that is in the data that comes with each release. It is possible to use any curve and that file can be also loaded into the projector. I have even seen files that use a different gamma curve for each of the primaries.
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post #19 of 38 Old 08-30-2008, 09:33 AM
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Quote:
Originally Posted by Erik Garci View Post

but my main point is that an S-shaped curve is not accurate to the DCI spec,

Thats not the case, the gamma isn't set in stone. Titles can and do have a PCF file that makes some serious changes to the projectors parameters, including gamma.

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Erik,

Do you have an explanation why DC can use a 2.6 gamma without apparent problems, considering that the projector CR is about 2000-2300:1 and in theater is limited by ambient to less than 1000:1?
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Quote:
Originally Posted by odyssey View Post

Erik,

Do you have an explanation why DC can use a 2.6 gamma without apparent problems, considering that the projector CR is about 2000-2300:1 and in theater is limited by ambient to less than 1000:1?

I was thinking the same. Most Lcos with native 15k to 1 have a hard time with anything more then 2.4
I can only think it is not a flat 2.6
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post #22 of 38 Old 08-30-2008, 10:52 AM
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Quote:
Originally Posted by Alan Gouger View Post

I was thinking the same. Most Lcos with native 15k to 1 have a hard time with anything more then 2.4
I can only think it is not a flat 2.6

It's a conventional 2.6 power function curve, not S shaped, and is used for most DC content.
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post #23 of 38 Old 08-30-2008, 11:23 AM
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Quote:
Originally Posted by odyssey View Post

Erik,

Do you have an explanation why DC can use a 2.6 gamma without apparent problems, considering that the projector CR is about 2000-2300:1 and in theater is limited by ambient to less than 1000:1?

Is this something you have the answer to? If so, I would be interested in hearing it. As far as apparent problems, I would say 2 things. First, they can use whatever gamma they want as long as the source is mastered correctly knowing that this is the gamma it will be displayed with. In other words, using a high gamma number on a lower on/off CR projector is a problem largely from the source being mastered assuming either a lower gamma number or higher on/off CR for display. The extra bit depth of DCI can help down low for certain artifacts, but the low CR down there is still going to be there.

I know that when I went to the presentation by TI at CEDIA or CES a few years ago where they showed National Treasure in a big theater, I thought the part near the opening where the kid is in the dark attic looked horrible. My memory is that I could hardly figure out what was going on and the blacks looked really bad. That is the kind of scene where if you have low CR between most of the stuff in the image and blacks in the image it can look pretty poor. When this came out on Blu-ray I checked it out with my RS1 and that scene looked way better than I remember on the DCI unit. It could have partially been memory, the way the thing was encoded, or TI could have been crushing things in that one presentation. I think I'll use my Panasonic AE1000 to try to figure out how that scene is encoded on the Blu-ray. Might be a good scene to compare an S-shaped gamma curve to a traditional curve.

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post #24 of 38 Old 08-30-2008, 11:31 AM - Thread Starter
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Added to the gamma degustation to do list.
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post #25 of 38 Old 08-30-2008, 11:33 AM
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No, I don't have the answer. Why would they choose 2.6 instead of lets say 2.4 or 2.2 if the mastering and display gammas are the same?

The performance of a DCI projector a few years ago is not representative to that of a current unit.
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post #26 of 38 Old 08-30-2008, 01:52 PM
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Quote:
Originally Posted by odyssey View Post

Do you have an explanation why DC can use a 2.6 gamma without apparent problems, considering that the projector CR is about 2000-2300:1 and in theater is limited by ambient to less than 1000:1?

The DCI spec describes transfer functions for encoding and decoding. The encoding transfer function is basically Y' = Y^(1/2.6), and the decoding transfer function is the inverse, Y = Y'^2.6.

If your projection system has a sequential CR of 2000:1, for example, then obviously it cannot produce luminances below 0.05% of the white luminance. So if the content contains those luminances, they can be mapped to luminances that are above 0.05%, or else they would be crushed.
Quote:
Originally Posted by odyssey View Post

Why would they choose 2.6 instead of lets say 2.4 or 2.2 if the mastering and display gammas are the same?

The combination of 2.6 gamma and 12 bits per component was chosen because it minimizes the visibility of contouring/posterization within the range of luminances for DCI.
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post #27 of 38 Old 08-30-2008, 02:40 PM
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Thanks Erik. I missed the encoding section of the DCI specs with the inverse of the 2.6 display gamma. I thought that the encoding might be at 1/2.2 and the decoding at 2.6.
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post #28 of 38 Old 08-30-2008, 08:46 PM
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Peter you will appreciate these images. They might be a little blasting bright for the camera but look great in person.
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post #29 of 38 Old 08-31-2008, 05:15 AM - Thread Starter
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Excellent detail Alan. I compared the two dolphin shots in different windows side by side, your saturation is a bit more intense(which is explained in terms of the Titan TIP& emulation) but there is much more detail apparent on yours. Of course it could be my camera.
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post #30 of 38 Old 08-31-2008, 08:16 AM
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Peter I use a tripod and the timer on the camera so no vibration.
Alan Gouger is offline  
Reply Ultra Hi-End HT Gear ($20,000+)

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