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CAVX

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Everything posted by CAVX

  1. I am staying with my Acoustic Vision AT screen. It is 1.16 gain.
  2. I have used those patterns on every UHD display I have calibrated and never seen that happen. And I have used the Panny 300, 400 and 900 as source. The 300 doesn't doesn't display over 1000nits, so it just white. The 400 and 900 can do out 4000 nits.
  3. Yes definitely screen size dependent. Nits is based on candella squared or the number of candles it takes to produce x amount of light over a meter by a meter of screen surface. The bigger the screen, the dimmer it gets. Some day, I will get a JVC.
  4. You are correct, at this point in time, there is no display that can produce 10,000nits. All displays should be able to show the flashing grey bars right out to 10000 if the contrast is not pushed too high. The white in the pattern is limited to the capabilities of the display. Being a full white, most modern displays typically reproduce it at about 300nits for flat panels. The only projector I have seen that did this pattern over 100nits (measured 126nits) was the BenQ W1700.
  5. I have never had a system crap out using that pattern (#3 of white clipping). If there is an issue, the pattern just displays as crushed whites.
  6. I'll try and keep this simple. RGB balance is the grey scale tracking from black to white. Ideally, you seek a point (shown on the CIE diagram) of D6500K. To get there, you need to find the precise x,y point where x = 0.313 and y = 0.329. The grey scale should be flat from 0 -100 generally expressed as percentages or IRE (Institute of Radio Engineers). Grey Scale is also expressed as numbers from RGB0 - RGB255. The differences between SDR and HDR are as follows - SDR has a range from video black of PC RGB16 to video white or RGB 235 (even though the range goes up to 255) to remain backwards compatible with CRT. The peak white for SDR is said to be no brighter than 100 nits or 29.29FL. HDR still covers the same range but does it much finer steps (0 to 1024 in a 10bit system). This gives finer gradients and hopefully banding is not visible. The main difference is that the whites continue well past 100nits out to 10,000nits. The reality is that an OLED TV might push out past 500nits and an LCD TV might be capable of 1000 nits. A projector is doing extremely well if it can push out 100nits. The lumanance chart is showing 100nits. For colour the CALMAN shows both a 2D xy and the Y is shown in the chart below that. The x,y points are what we typically use to compare the size and mapping of of the colour gamut. The Y is the lumanance or how bright each colour is. Your chart shows this as a flat line meaning all Y values are at 100%. Where HD video uses rec709 colour, UHD can use a colour gamut far larger like P3 (used by D-Cinema) and BT2020. Rec 709 is 75% of P3 and P3 is 75% of 2020. Using PQ gamma, each colour is supposed to be able to reach 10,000nits.
  7. I agree with the 6 to 7, especially on new projector tech like laser.
  8. The idea of constant image height is for all images to be projected at the same height, not to fill the Scope screen. Your JVC has two anamorphic modes and up-to 10 programable zoom modes. There is a 4% difference between true 16:9 and 1.85:1. For both ARs, you would use B mode, but you could also apply a small amount of zoom to rid the slivers. Same as 2.00 or 2.20. With mode A, it is based on 2.37. Most Scope movies are either 2.35 or 2.40. With 2.35, about 2% of the image is lost with the black bars. For 2.40, you again see slivers of black. Whilst you can't do anything about the 2.35 crop, you could create a small zoom for 2.40. You would need a 2.40 screen.
  9. I use these patterns all the time and have never seen a system crap out. If the contrast is too high, then you get white crush.
  10. Sounfirm as in Fox Studio, Sydney? I visited twice. The first time was during the the time they were THX certified, about 2002, and SW2 AOTC had just hit DVD. The 2nd time was well after SW 3 was done, so probably mid 2006. There was a massive difference between visits. I was blown away with how quiet the main mix stage was in 02, and really surprised how noisy it seemed in 06. In 02, they claimed it cost $30kUSD to hold that certification. At the time, we were about $0.54usd. What would have changed in that time remains to be answered. If the room was able to achieve the noise criteria of THX in 02, surely they would have been able to maintain that for the following years.
  11. One of the most important things I learned at the ISF course was that grey scale is a specific x,y point and not just 100% RGB. Grey in video is x:0.313, y0.329. Display type pending, 100 green may move the point higher (or lower) than y:0.329. If that happens to read higher (example y:0.332), then yes, your images will have a green hue to them.
  12. I have no issue with DIY. Do you have a colorimeter? Getting the grey scale to D6500K is not sometime you will not do by eye, especially for 10 point adjustments on a TV.
  13. When does SOLO come out? I got PREDATOR and like T2, it is the best version of the film to date. My original BD is as grainly as a bowl of rice, the Ultimate Hunter Edition was scrubbed clean to the point where Arnold looks like clay in the opening sequence. Not to mention the cropping back to 16:9 UGH! But this is nice. Enough grain to look like film, but clean like we expect from UHD and back to the TE AR of 1.85:1.
  14. The colours and the details are awesome, but the stand out for me is the lightning strikes in "Deserts" where you truly see the point of HDR. I should probably buy a 2nd copy and add it to my demo material.
  15. There are very small losses with an AT screen as even a weave passes light through the fabric. However, the overall gains in AV far out weigh these small losses, so don't let the idea put you off going at. I've had AT since 2006 and there no way I would go back to a solid screen with speakers above or below the screen.
  16. It is an averaging thing where the mic in a SPL meter is not as accurate as that of a RTA. With the RTA, you can set the SW to 10dB higher than the main channels. If you set the SW at 79dB with a SPL meter and check it with RTA, it reads at the correct level of 10dB.
  17. It seems those HDR-10 patterns work as well with this conversion, though there are some limiting things going, it is still better than trying to adjust using actual pictures. There are two Black Crush tests and it seems my DLP can only go down to 2% black, so again, using the side pillars of the 4x3 mode, I can adjust brightness until I can see all the visible black bars as well as level match the black background to the side pillars. There are three White crush patterns and the first one up to 1000 nits behaves like any SDR contrast pattern. Take it as high as it will go whilst being able to see all the bars. Easy. Recheck brightness.
  18. I'll just zip up my flame suit now. The definition of Gamma is " a display's no- linea response to an electrical signal." In theory, Gamma is twice the light out for twice the power in, or 45 degree from 0 (black) to 100 (white) on an x.y chart. In the real world, it does not happen that way. A capture lens and image chip does one thing to the signal, and we compensate on the display end with our gamma curves. The curves are created to try to bring it back to that "perfect" straight line. Our eyes are non-linear, so Gamma curves in a TV are now now user selectable to better match the room environment that the display is actually being viewed in. For the history of TV, the room is supposed to be dark with the ambient light being no brighter than 10% of the peak white light from the display itself. Does that happen in the real world in the homes of the TVs I calibrate? No! Almost never. In most homes it is white walls and ceilings, white tiles on floors and big windows. Light can simply NOT be controlled. I like to have the customer in the room when I calibrate their display. And I explain as simply as I can, the process and what I am doing. When I explain gamma to a customer in their home, I like to refer to it as the rate at which the display comes out of black. The higher the number, slower it comes out (which works better in a darker room). In a light or bright room, we have to go lower value or correction curve to come out of black faster to allow us to actually see the shadow details. I don't like doing it because it goes against everything I've been taught, but in some homes, I have no choice. So what we think of in "text book" goes right out the window sometimes. In the end, I have to get as close to the standard as I can and still keep my customer happy. Whilst I learned so much from doing that ISF course, I wish there was a support network . If there is, I don't know about it, so I sometimes feel like the terminator " skynet presets the switch to read only and we are sent out alone". This industry has changed more in the last 5 years than it has in the previous 20 or maybe even 30. Gamma in Software: Now I have pretty much bought every version of T2 on packaged media that it has been released on. There is a HUGE difference between the BD of Skynet Edition and the latest 4K release where the BD is much darker than the previous release. If the Skynet Edition was mastered at 2.2, then that is crap! Apart from the over use of DNR, the new transfer looks stellar. Comparing the two is like upping the brightness control of the display for the Skynet Edition. The lower midtones are quite bold and you see things that even James Cameron says (in the running audio commentary of one previous release) were not seen on film. Therefore, the latest version is much closer to the Director's Vision" or what was seen on film IMO. I am still running an older 1080P projector, but am now using the OPPO 203. HDR-10 has been a challenge and then TLJ comes out in Dolby Vision and throws a really big spanner into the works. HDR-10 is an open standard and allows studios to master at varying levels. The OPPO allows user tweaks to make the picture better (or worse). Dolby Vision is a closed standard and it locks out everything. And I get a message that states "user controls can not be used for Dolby Vision content. So I had to find a work around to make this work on my system, and some (most) or what I have done is thinking right outside of the box. The Last Jedi has a certain look, so how much of that is the directors vision verses technical error? I don't know. The Matrix on the other hand is a complete different beast. I don't have any other DV titles to compare at this time. In the latest FW update for the OPPO 203, a huge white line was created down the left hand side of the 16:9 image by the player. Very annoying on my CIH system when viewing 16:9 content. OPPO gave me instructions of how to create a system log based from thew player, save the txt file and email it off to them. Hopefully they can find a solution to this from the data the player generated and fix this in the next FW. In the meantime, I have found that using the "Convert to Dolby Vision" in the set up has worked for me. This is where it gets really interesting as I have had to re-calibrate everything. So my first screening of The Last Jedi in Dolby Vision was crappy based on a system set up for HDR-10. It looked smokey. I didn't like it. It also killed the 21:9 mode, but that is another story. So I did some experimentation and found that you can really go to town on the contrast and brightness. Because there is no "test patterns" for Dolby Vision, my work around was (did i say outside the box?) quite different, but it has given me a result that works. To set the black level, I switched to the 4x3 mode of the projector and whilst watching the letterbox bars, set brightness to match the projector generated side pillars. This sets what I would call the "back floor of the projector" or as black as this older DLP can go. I then found that the image was dark, so I had to up the gamma, then reset brightness/contrast. So I had to go from 2.4 to 2.8. Contrast was set using (again, due to no test pattern) the scene where Kylo smashes his helmet. I paused the image and used the bright white sparks and shattered glass as my reference. I took contrast way up until it white crushed and then backed it off to allow me to see the details. Later I noticed other lights in the rebel ships were crushed, so a click or two down revealed the details I was meant to see. So contrast on my system has gone from typically around 50 up to 78! Brightness is currently at about 42. At the 2.4 gamma, I had to drop brightness down into the 30s to level match which caused the image to be darker. So this is how user selecting a gamma curve can be made to work for me. Increasing the correction value, allows me to increase the brightness setting. It maintains the black level, but gives the lower mid tones a bit more life. Once I was OK with brightness/contrast, I took a white field measure, then set colour levels at their percentage level against white. I am finding colours to be bright, but not harsh or over saturated. The OPPO 203 has a variable HDR to SDR slide control as part of the converter. If this slide was too low, the peak whites in the signal would flash almost displaying between crushed whites and what we should be seeing. It has been a challenge to find that fine balance where this flashing does not occur and still have a nice bright image. Since converting to DV, this does not work, but the flashing issue is no more. I'll leave it there for now. I'm sure after reading this you will be like WTF?
  19. I won't be that harsh but what I will say is that using the S-Curve gives the image real pop. It makes you wonder why we weren't doing this sooner. Images have depth now. What I find interesting is that prior to getting iSF certified, I could never get a gamma of 2.2 (measured on the charts) on my system. The one time I did, and it killed contrast. It measured flat and also looked flat. Since the training, I understand what it does and how to use it. But that 2.2 number value is questionable, because a gamma of 2.35 looks better. Part of me thinks it was chosen because 2.2 is generally in the middle of the range of the gamma options and nothing more. As for program mastering, just look at Universal's botch up on Blu-ray for FLASH GORDON, TOTAL RECALL, TERMINATOR 2 and the list goes on. All of these have a gamma other than 2.2 used for mastering. The quick fix on my system was to use a higher value and readjust brightness/contrast. And at one point, I had a "universal" mode set up on my projector for these titles. .
  20. Update OPPO have given me a task of creating a log and saving it to USB. I have done what they have asked and send off the saved file. I do hope that they can find an answer to this. In the meantime, I found that I can convert HDR-10 to Dolby Vision and the line is gone. The problem here is that I get a message on screen stating that user controls can not be used with Dolby vision content. This includes the 21:9 mode. Lucky for me, my projector scales DV, so all good for now.
  21. Ticket has been submitted.
  22. Thanks, on to it now. It says latest FW is UDP20XAU-60-0224 as of July 3. Yet mine is 20XAU-60-06252 and I am sure it came through July 9.
  23. Is OPPO Digital through Interdyne or OPPO direct? There used to be an email automatically generated with the phone App for the 103D. If the App glitched at all, the email prompt would come up and they sorted my last issue pretty fast. I have never used the 203 App.
  24. Latest FW update notification came through the other night. I had been watching BDs but noticed that the FW had added DV stuff. Nothing of use for me. Then I load a UHD disc and I see this white line on the left side of the image. Only for HDR-10, not Dolby Vision discs. Anyone else got this issue?
  25. It seems that part of the OPPO 203 Tone Mapping is to create an S -Curve, so anyone using the OPPO 203 with the Tone Mapping FW should have this.
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