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Spears & Munsil Calibration Advice - Page 3

post #61 of 162
The Grand Canyon is my go to clip for showing off 3D.
post #62 of 162
Quote:
Originally Posted by sspears View Post

When adjusting contrast you.

1. Want to get contrast as high as possible, below the pointing of clipping.
2. Produce the smoothest gradient.

--

1. Start with either the dynamic rang high, or contrast pattern, and turn contrast up until the last bar on the bottom right clips. Now turn contrast back down to see that last bar. ie you make it clip and then stop it from clipping, so you know the actual clipping point.

This tells you the top end of white.

2. Go to the clipping pattern and make sure RGB are not clipping. If they are, try turning contrast down further to see if you can make them not clip. If so, then that is the top point.

3. Now that you know the top end, go to the contrast pattern and turn contrast up and down (below the clipping point) and see if the gradient (ramp) in the middle of the pattern gets better or worse. Find the spot with the nicest ramp where you can get contrast as close to your clipping point as possible.

If your display, player, or path is clipping everything above 235 on the constrast / dynamic range high pattern, then start with the clipping pattern. If only white is clipping, make sure not to clip RGB.

I have your disc. Can you elaborate a bit on what you mean by "better", "worse", and "nicest" please? I will look in the website articles too.
EDIT: I found some illustrations in the contrast article on your website. The extreme of major clipping (contrast too high) is easy to see. The differences otherwise are fairly subtle looking. I suspect that the differences from a point or a few points of contrast adjustment below where white and the colors clip is not going to be that easy to discern.

I have to put the disc in and look at that. I do know that I have a contrast setting of 92 on my Samsung LCD based on the colors clipping patterns looking right, and the contrast just seem a bit uncomfortable and fatiguing at times.
post #63 of 162
Quote:


I do know that I have a contrast setting of 92 on my Samsung LCD based on the colors clipping patterns looking right, and the contrast just seem a bit uncomfortable and fatiguing at times.

It is possible you need a bias light behind your display to ease the fatigue.

The gradient should be a smooth transition from black to white. A nice continuous tone much like a sky transitions from a light blue to a dark blue.

I previously owned a Samsung 720p projector. The point below clipping would produce 8 distinct lines/bands in the gradient. Lowering contrast by one would reduce the lines/bands to 4. Another level down and there were 2 lines/bands. Onoe more level and the lines/bands were gone. It was virtually perfect. If I went another level down, the lines/bands would return. There was a perfect setting on that display.

My current 1080p Samsung is not as smooth. My Panasonic 3D plasma has bands all over the place. They are all an equal distance from each other and I can't smooth it out no matter where I set contrast.

Best would be perfectly smooth, which is what the pattern actually looks like. Bad would be like my Panasonic. Better would be fewer bands. The fewer bands the better.
post #64 of 162
Quote:
Originally Posted by sspears View Post

They are in fact the same bug. The saturation -2 is a better fix than contrast -1. Don't perform both. Neither really fix the problem.

So what is this bug doing exactly? Oversaturating the colors and clipping white?
post #65 of 162
Quote:
So what is this bug doing exactly? Oversaturating the colors while also clipping white?
Color space conversion error. We have since found other devices that have the same error.
post #66 of 162
But what are the effects of it exactly?
post #67 of 162
Not every RGB values is reproduced as the expected value. The amount of error is different between R, G, and B.
post #68 of 162
So if you set the Edge to output the same colorspace that it is receiving then there is no problem?
post #69 of 162
Quote:
So if you set the Edge to output the same colorspace that it is receiving then there is no problem?
No, the problem is always there. Everything gets converted to RGB inside of the VP50, 50Pro, Edge, and Duo. One of the features of doing this is the ability to twist the color space. It is also required for CMS.

You should also never use the auto setting. Auto is not about quality, it is about compatibility. On some displays, auto will use the wrong resolution and or color space. This applies to any device that has an auto color space option. Auto uses the EDID in the display, which describes the supported resolutions and color spaces. It also provides a recommended resolution and color space. This information is wrong far too often. If this was ever programmed correcly, it would clean things up.
post #70 of 162
Geez, it seems the more money you spend on components the more problems there are.

Am I correct to say that these variations in R G B levels wouldn't really be noticeable to the eye?
post #71 of 162
Pixar noticed that their content was off by one pixel value with a Blu-ray player that had the same issue. Its their content so they know what it should look like.

I bypass the Duo, for Blu-ray. For TV (All HD programming) I go through the Duo.

As far as we have come, there is still a ways to go before we are taking full advantage of Blu-ray. We have come a long ways since the Faroudja LD-100 that converted 480i to 480p for $15,000.
post #72 of 162
Quote:
Originally Posted by cinema mad View Post

Hi Stacey,
If Im comprehending your above comment right I take it the VP50/pro would also contain the same bug as the Edge and therefore best to set saturation to -2 also, unless your using 4:2:2 in/out of the DVDO then the bug would'nt have any affect ?..

Sorry if I missed a response of yours, Stacey, but is he correct to say that the bug does not apply to 4:2:2?
post #73 of 162
The bug is there on the 50, 50Pro, and Edge regardless of input/output format. It is fixed on the Duo with build 79.
post #74 of 162
Quote:
Originally Posted by WebEffect View Post

Geez, it seems the more money you spend on components the more problems there are.

Am I correct to say that these variations in R G B levels wouldn't really be noticeable to the eye?

Agree with you on first sentance. Starting with a basic chain of BD player > Display really is important before introducing any equipment in between.

One of the best pieces of advice I got from Stacey (and I have needed and received plenty) was to first go direct to my display and check out what my display (with the S & M disc) prefers, before inserting anything else into the chain.

What an eyeopener that was because Oppo 80 > Toshiba LCD using the S & M disc showed contrast clipping massively, no matter what level of TV contrast I used, for anything other than RGB output from the BD player.

Part of my problem with Duo in circuit was of course the Duo bug but mostly it was outputting YCbCr to my TV with the above problem and then compensating with the Duo contrast.

Incidentally, if I leave it on 'auto' and let Duo decide, it selects YCbCr so the point Stacey makes about not using 'auto' is well made (I thought it was only my TV that not only had preferences but then signalled the incorrect one).

Thanks again Stacey.
post #75 of 162
Thanks for your responses, Stacey.

I was looking at the white crosshairs on the Chroma Alignment pattern, and the three horizontal lines appear greenish and the three vertical lines reddish. However, this happens both through the Edge AND when connected directly from the player (Panasonic BDP80) to the display (Pioneer Kuro PRO101)

Yet the crosshairs look perfectly white when there is natural light in the room (not artficial) or when I look at the crosshairs up close, from a foot away or closer, even in the dark.

Is it showing a problem? If so, would it be the Kuro or the player?
post #76 of 162
Can you take a picture and post it?
post #77 of 162
This is the best I could do, it doesn't show up all that well, but I hope it's useful. The cross-hair that's from up close looks noticeably more uniform, though...

http://www.flickr.com/photos/56167437@N08/?saved=1
post #78 of 162
I bought a new bulb for Panny 100. Using the Spears disc I adjusted the contrast with no problems. Two days later the projector washes out on dynamic contrast and cant be tamed. Popped in the old bulb...No problem...Plasma...no problem...Weird thing is: projector image looks fine/great with new bulb...Spears site suggested that this could be a component problem(bulb). Anyone ever hear of this before??? I'm tempted to ask for a replacement bulb unless someone can suggest otherwise. Thanks.
post #79 of 162
Simply re-installing the old bulb fixes it? Just want to make sure no other control is somehow enabled or the color space is some how changed along the way.
post #80 of 162
Yes..Simply replacing old bulb(1850 hours) fixes issue. We tried it twice. We're going back into the cal jungle tonight and see what we can do because of a discovery we made this afternoon. That is, we tried the disc with a brand new PS3 hooked up to the plasma and re-created the same effect immediately. Then, remembering your advice, we found the 'super-white' setting and presto! Coherent display! BTW,,,, I am using OPPO-93 in tandem with my projector and Panny plasma. We'll try both players and see what shakes out...I'll re-check output settings on projector beforehand and see what happens...One more thing...the disc works beautifully on the plasma and thanks for the reply..
post #81 of 162
No improvement with either player(93/ps3). Re-tried old bulb one more time and bingo...it works...Very strange..Oh well. I'd like to try a replacement bulb but i'm wondering on what grounds I'd have since I get a great picture(laugh!). It may wash out with the test, but that doesn't translate to movies/video...I have 90 days to think about it and gather more info. I really like the S/M disc and I highly endorse it to anyone. How's that for a plug.

Happy New Year All
post #82 of 162
I just found this thread and noticed the talk of the colourspace bug in the Edge. Does this apply when passing 1080/24p at rec709 or is it only when using the Edge to upscale? I didn't think I'd had an issue with contrast (I usually set it in the display such as to clip above 235, but I know that's a personal choice) I hadn't realised that there could be an effect on banding by adjusting the contrast too, so thanks for this information. The latest 1.6 firmware (for 3D mostly) mentions about "Improved accuracy of color space conversions and handling of non-video signal levels" so I wonder if this will resolve what you're talking about or if it means something else.

I was planing on getting an Oppo 83 which comes with this disc (or rather it did from the old UK supplier) and now it's likely to be an Oppo 93/95. I may just buy the disc anyway as it's likely to be a while before I get either player.

...Just when I thought I'd sussed out all the settings and achieved a near perfect calibration on my Edge/VideoEQ Pro/HD350 combo: At least it measured well and to be fair I think it looks better than it ever has, but this makes me want to recheck a few things.

I've been using 4:2:2 into the Edge, with it outputing 4:4:4 into the VideoEQ Pro (24 bits rather than 20 bits as displayed by the Edge's output info). This then allows the VideoEQ Pro to take 8 bit in and it can then output in 10 bits which means the LUT 'calculations' can be maintained at a higher bit depth, which I understand this helps with banding...I guess I need the S&M disc to check and optimise these settings.
post #83 of 162
Quote:


Does this apply when passing 1080/24p at rec709 or is it only when using the Edge to upscale?

The bug always occurs.

Quote:


The latest 1.6 firmware (for 3D mostly) mentions about "Improved accuracy of color space conversions and handling of non-video signal levels" so I wonder if this will resolve what you're talking about or if it means something else.

This sounds like it might be the same fix as the Duo.
post #84 of 162
Quote:
Originally Posted by sspears View Post

The bug always occurs.

This sounds like it might be the same fix as the Duo.

Thanks. I wonder how this would effect the calibration I've already done. I rented an i1Pro so although I profiled my i1LT it probably won't be as accurate, so I guess I'll just have to leave it for now and live with possibly clipped colours. Using other test discs though I've not seen signs of clipping even on RGB flashing bars. I plan to order the S&M disc now anyway to investigate the best input options to my HD350 and do the various performance tests. Then I'll re-rent the i1Pro again sometime.
post #85 of 162
Thanks to this thread it got me thinking again about contrast settings: I found a test pattern with a grey ramp and checked on my TV and my projector (both contected via my Edge VP). I found that I could set the TV's contrast to a sweet spot where the ramp was smoothest (though not perfect) but I also knocked the Edge contrast to -1 as recommended on here.

I checked on my projector, where the ramp was already much smoother (possibly due to the VideoEQ outputing in 10 bit depth after applying the LUT?). Again a small amount of tweaking found a sweet spot too with virtually no visible bands when viewed from my seat. I have two similar settings saved with the only difference being the gamma changed from 2.2 to 2.3 and found that these also needed slightly different contrast settings to get the smoothest ramps.

I never would have considered this adjustment had I not seen this thread, so again it shows that after 2+ years of calibration I'm still learning. I'd previously accepted that the ramps didn't look smooth due to the limitations of the display. I guess it's more placebo now, but watching a HD recording of I am Legend tonight looked really great and not a trace of any banding even when I went back onto some live SD broadcast afterwards.

I'll have to order the S&M disc to check a few other items, then I guess I'm going to have to re-rent the i1Pro again to check if I've messed up my calibration with these changes (and re-check the ramps again during to make sure they stay optimised ).
post #86 of 162
If you are using the new Edge FW that claims to fix the color space, I would set contrast back to 0 in the Edge.

We continue to learn as well. The clipping pattern on our disc was designed for one specific test and has since exposed other issues we were unaware of the time.
post #87 of 162
Kelvin1965S -- The Oppo BDP-83 is out of production. The new BDP-93 (improved and has 3D capability, same price) no longer includes the S & M disc. Therefore, you might as well just go ahead and buy it now.
post #88 of 162
I haven't updated the Edge yet (didn't want to dismantle my equipment over the Christmas break to get to the USB plug), but I'll do it soon and reset to '0' (and recheck for banding ).

CT_Wiebe, thanks for the heads up re the '93 not including the disc, I knew about the '83 being discontinued, but I may pick one up used if I see a realistically priced one: Over here they still seem to ask nearly as much as the 93 is expected to sell for, which I don't think is worth it.

I understand there are other tests on the disc that might help deceide things like whether my displays work best fed with 4:4:4 or RGB so there may be more revealations for me yet to come.
post #89 of 162
For brightness, should you be able to see the checkerboard even on a non-dlp display? The instructions and online specifically talk about a DLP display being able to show the checkerboard but nothing about whether LCD and plasma users should as well. I have the g25 and have my current brightness set with one notch giving the checkerboard, but obviously I could set brightness lower if I don't need for it to show. I believe the checkerboard is 17, but the disc instructions are vague in saying I should barely see above 18, and possibly 17. If I go with 18 I can set brightness lower which is probably the best for gamma and black levels, but if it's supposed to be showing barely 17 then so be it.
post #90 of 162
Quote:


should you be able to see the checkerboard even on a non-dlp display?

Yes. The checker is at black and above black.
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