AVS HD 709 - Blu-ray & MP4 Calibration - Page 109

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Alluring,

A big thanks for the MP4 version,I just used it to calibrate my Panny 55GT30/2.1 and it looks great...Thank you buddy...

is there an archive for the older versions? I need v 1.2b to burn to a dvd.

thanks

You can download the 1.2b from SpectraCAL.

Here is the link.

thanks ConnecTEDDD

I have a question related to gamma accuracy of the test patterns on the AVS HD 709 calibration disc. I use Chromapure and the i1 Display 3 Pro (calibrated) probe. I have found that when using the AVS HD 709 calibration disc if you use the gamma test patterns to measure the display's gamma the results are not the same as compared to using the AVS calibration disc's full screen gray scale patterns. This implies that the one or the other is not accurate. That is the 10%, 20% etc. patterns under the gamma section should be identical to the corresponding value pattern under the section for doing gray scale measurements, but it appears there are differences for at least some of these patterns. Perhaps this has been covered in this very long thread, but have others found this same issue with the AVS calibration disc?

Are you calibrating a crt or plasma? if so this can cause the luminance values of the windows vs fields to be different if the power supply isn't quit up to the challenge. the reason is it takes more power to display a full field pattern vs its corresponding window pattern. If the power supply starts to choke it will cause a reduction in brightness as voltage levels (ire) are increased.

I can confirm after using this test pattern disk for some time that the fields are accurate when compared to the window patterns using my Eye One Pro spectro, Calman and a good DLP.

I've seen the difference when calibrating a couple of JVC DILA front projectors, an Epson front projector and a Mits DLP rear projection TV. Not a big difference, but some difference in the resulting gamma curve was seen when using the gamma screens vs. the gray scale screens. I'm using ChromaPure with a i1 Display 3 Pro (calibrated). I'm using the patterns under the ChromaPure section on the AVS HD disc.

Well, I cant speak for the chroma pure patterns on the disk, only the calman patterns but I doubt they would be different. Its interesting that you see this with a Mitsubishi RP as that's what I use (wd-65837) and the differences I see are well within the meters claimed level of accuracy . I suppose the real question is how much of a difference are you seeing. is it enough of a difference that its going to be visible and/or is the difference so small that the sets controls would not be able to even adjust to compensate for the difference without throwing the result of even further?

Since your meter is a non contact meter that is susceptible to stray light contaminating the readings, I have to wonder if perhaps the reason you have different
readings with a field pattern could be the result of the meter reading the pattern across more of the screen. Since most screens don't have absolutely consistent light and color across the entire screen, having the pattern on the full screen could cause the meter to see these variations, causing a slightly different reading as a result. Ambient light can throw off a meter reading as well. With a field pattern there is more ambient light as a result of more light bouncing of walls. The color of the walls, ceilings and other reflective surfaces can pollute your meter readings.

You will find that the i1d3 will fluctuate at the top end as much at 2% +- make the gamma curve different almost every time you read it. Same with the C6 but it is withing the meters spec. increasing the number of samples will smooth out the bounce a little

so i was using the white clipping pattern to adjust my contrast, and no matter what i do i just can't get rows 235 or higher to flash - even turning contrast all the way down.

is my white crushed?

you are going to have to provide a lot more information.

computer monitor or tv?

dvd or computer for the source?

which patterns are you using? (Avia, GetGray, AVC, etc)

input type?

Sorry. Here you go.

HTPC -> AVR -> Epson 8100 (all via HDMI)

AVSHD709 patterns

the 1st thing I'd check is the video card settings on the HTPC. Depending on the brand. it may be labeled "PC or Video" or "16-235 or 0-255" or "RGB High or RGB Low" change it and see if your output on the monitor changes.

Check the menus in the AVR to see if there is a similar setting.

To make things easier you may want to temporarily connect the HTPC direct to the monitor, and once the video card output is sorted, put the AVR back in the mix.

Video Card is set to YCC444 0-255.

AVR is an HDMI passthrough, it's not doing anything.


My question is: what does it mean if I don't see any bars higher than 235 flashes? Is this normal?

something in the chain is cutting off the signal above 235, and likely below 16. What are the other setting available? did you try them?

Can you change your video card settings to 16-235? Having it as you are leave no room for wtw and btb

i am sorry, i think i might have presented the wrong information.

the white clipping patterns goes like this right?

235 234 233 231 230 229 228......................................................... ...........16

if that's the case, then what i meant is i can not see anything lower than 231/230 flashing.

i am at work right now and can't pull up the patterns. sorry

changed my video card setting to dynamic > limited 16-235 and i am able to get all the bars on both black and white clippings to flash.

question on white clipping: is it ideal to get bars 244 and lower to flash?

the pattern said to let 231-235 flash, however reading the manual it seems to indicate that i want at least 244 and lower to flash when setting contrast.

so, which is correct?

100% correct would be 235 and below flashing, however most prefer 237 and below, myself inclusive. This leave room for information blacker then black

Not sure blacker-than-black is *necessarily* related to where you set contrast, but choosing the level past which you no longer see flashing (235? 240? higher?) is an interesting question and it has been discussed forever here on AVS.

For an expert's opinion, see post 2347 in this thread. http://www.avsforum.com/avs-vb/showp...postcount=2347

Also this was discussed at length in the following thread, starting a few pages in. Page 11 is a typical page:
http://www.avsforum.com/avs-vb/showt...240153&page=11

My takeaway: I set it so I can't see blinking over 240. The difference between 235 and 240 is minimal. But if you can see 254 blinking you're probably giving up a little dynamic range for no real reason.

(Further upstream in the video chain, I accept you want to preserve *any* information you can, but we are talking about setting the controls of your display, the last link in the chain, where your choice is being able to discern the occasional stray pixel at 254 vs. having a brighter picture: I'll take brighter picture. The point of the above discussions was there just isn't that much real content that lives over 240 by the time it gets to the display.)

Sorry ment whiter then white ofcource

I'm receiving totally different greyscale readings when using the large APL feilds or using the windows for greyscale.....which should I be using? Any advice? Thx

Display 3Pro
Chromapure
Mits 65831 with dynamic iris
PS3

Define "totally", it's pretty common to get smallish (say 50 Kelvin changes) depending on APL. In those cases they are both "right", your measurements are just telling you that you have an APL dependent white balance. Also, turn off anything called "dynamic" when doing a calibration.

Currently I have the greyscale set using the APL windows and everything is smooth, I switch over to the regular windows and blue is extremely low compared to red and green.....not even close. The Blue is about half of what it was all the way from 20 to 100 ire.
Can't turn off any iris settings....it sux!!!

In that case I would try viewing some reference material after calibrating first to one set of patterns and then to the other and see which is more agreeable. You could also try to split the difference and find some settings which move the two sets of patterns closer in measured performance to each other.

I would try adjusting the gray scale with full fields.

I did it with full fields as well.....those pretty much matched the same settings as regular windows.

in for later