Epson 8700UB use extended or normal video range? - AVS Forum
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post #1 of 30 Old 10-18-2010, 06:22 AM - Thread Starter
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So I am a bit of a newbie at calibrating (done a couple of displays without a full CMS) and now I am trying to calibrate my epson 8700UB projector.

I am a bit perplexed on which mode I should be using for the video range.

In my setup, my blu ray player goes through my onkyo pre-pro to my projector. I am using the AVS HD disc and a i1 colorimeter.

On the AVS black level screen, if I use "normal" mode I get no flashing bars below black (as expected) however I get white levels all the way up to 255 (depending on my constrast level obviously). I guess I would be expecting information above 235 to be clipped off along with info below 16. If I set it to expanded, I get the below black (16) bars and the above white (235) bars.

So it looks like a simple answer, of course just use expanded but I am wondering if the below black information is really there or if the Epson is simply "streching" a 16-235 range to "fill" a 0-255 range in? When watching something (movies, football etc...) I prefer it set to "normal". If I set it to expanded everything looks washed out and undersaturated.

I am wondering if this is the cause of the issue outlined in great detail from another poster here about undersaturated colors. http://www.avsforum.com/avs-vb/showt...7#post16166537
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post #2 of 30 Old 10-18-2010, 08:59 PM
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Quote:
Originally Posted by engelba View Post

So I am a bit of a newbie at calibrating (done a couple of displays without a full CMS) and now I am trying to calibrate my epson 8700UB projector.

I am a bit perplexed on which mode I should be using for the video range.

In my setup, my blu ray player goes through my onkyo pre-pro to my projector. I am using the AVS HD disc and a i1 colorimeter.

On the AVS black level screen, if I use "normal" mode I get no flashing bars below black (as expected) however I get white levels all the way up to 255 (depending on my constrast level obviously). I guess I would be expecting information above 235 to be clipped off along with info below 16. If I set it to expanded, I get the below black (16) bars and the above white (235) bars.

So it looks like a simple answer, of course just use expanded but I am wondering if the below black information is really there or if the Epson is simply "streching" a 16-235 range to "fill" a 0-255 range in? When watching something (movies, football etc...) I prefer it set to "normal". If I set it to expanded everything looks washed out and undersaturated.

I am wondering if this is the cause of the issue outlined in great detail from another poster here about undersaturated colors. http://www.avsforum.com/avs-vb/showt...7#post16166537

Video levels use the range of 16 - 235; so the setting of "Normal" is correct (do not use Expanded, which is for computer levels 0 - 255).

The correct way of setting contrast is to make sure the bars below 235 are flashing (so that you won't lose white level details). Whether the bars above 235 are flashing is not important (as virtually there is little or no video content that is using video levels above 235). You may want to crank up the contrast as long as clipping below 235 does not happen; but you need to watch out for undesirable results when contrast is set too high, such as color shift, eye fatigue caused by being too bright, etc. You have the i1; so that would be an easy way to set the contrast properly - meaning to achieve your preferred brightness (no matter it is 12ftL or 16ftL).

Enjoy your projector!
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post #3 of 30 Old 10-19-2010, 06:30 AM
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Greetings

from a calibration perspective ... we want to see all the detail in the above white area so expanded needs to be set. Film is mastered out to the end ... rather subjective call to say there is nothing out there so you don't need to see it.

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post #4 of 30 Old 10-19-2010, 10:01 AM - Thread Starter
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Quote:
Originally Posted by Michael TLV View Post

Greetings

from a calibration perspective ... we want to see all the detail in the above white area so expanded needs to be set. Film is mastered out to the end ... rather subjective call to say there is nothing out there so you don't need to see it.

Regards

I would agree here but I suspect there is something else going on here. Expanded, which shows below black (BB) and whiter than white (WTW) patterns, makes the actual picture look totally washed out.

I can't understand why BB are clipped off in "normal" mode but WTW are not. I am just wondering if Epson is "expanding" the range on its own.... i.e. taking a 16-235 signal and stretching it into a 0-255 signal.

If it was doing this, would this manifest itself during calibration as undersaturated 25%,50%,75% colors? (presuming you have calibrated on 100% saturation)
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post #5 of 30 Old 10-19-2010, 11:04 AM
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Set the Epson to expanded. This is the correct setting. Otherwise, BTB and WTW info below 16 and above 235 is clipped. If you set it to normal, info below 16 and above 235 cannot be seen when you look at a calibration disk that contains patterns that display BTB and WTW.

Trust me on this. All the Epsons (6100, 6500, 8100, 8350, etc) all act this way.


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post #6 of 30 Old 10-19-2010, 11:18 AM - Thread Starter
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Originally Posted by Kilgore View Post

above 235 cannot be seen when you look at a calibration disk that contains patterns that display BTB and WTW.

But this not the case.... "Normal" will show patterns above 235 and "clip" below 16. Extended shows everything (as expected) but the picture looks severly washed out, even when I adjust brightness and constrast to not show BTB and WTW patterns.

I will do some more research and post some actual data from colorimeter.
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post #7 of 30 Old 10-19-2010, 07:55 PM
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Quote:
Originally Posted by engelba View Post

But this not the case.... "Normal" will show patterns above 235 and "clip" below 16. Extended shows everything (as expected) but the picture looks severly washed out, even when I adjust brightness and constrast to not show BTB and WTW patterns.

I will do some more research and post some actual data from colorimeter.

You may be correct about "normal". Perhaps when I saw that BTB was clipped I assumed WTW was too. Either way, extended is still the way to go.

If the picture looks washed out with extended, you probably have contrast set too high. When my contrast is set properly calibrated, I can still see 4 of the bars above 235.


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post #8 of 30 Old 10-19-2010, 08:32 PM
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Quote:
Originally Posted by engelba View Post

I am just wondering if Epson is "expanding" the range on its own.... i.e. taking a 16-235 signal and stretching it into a 0-255 signal.

If that is the case, you better avoid setting it to "Expanded". From my experience, any device (no matter it's a source device or the display) that takes the original video range 16-235 and "re-scale" it to 0-255 will very likely introduce scaling artifacts that is easily noticeable. Color banding is one of those. You can probably see it when you pull up a grayscale ramp, in which the black-to-white ramp exhibits banding / contour lines.

Since you can see bars above 235 flashing when you set it to "Normal", you're losing nothing in the white level, and the picture looks good to you without wash-out or black crush (so it indicates the black level is set correctly). What do you worry about?
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post #9 of 30 Old 10-19-2010, 09:39 PM
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Quote:
Originally Posted by dominickwok View Post

If that is the case, you better avoid setting it to "Expanded". From my experience, any device (no matter it's a source device or the display) that takes the original video range 16-235 and "re-scale" it to 0-255 will very likely introduce scaling artifacts that is easily noticeable. Color banding is one of those. You can probably see it when you pull up a grayscale ramp, in which the black-to-white ramp exhibits banding / contour lines.

Since you can see bars above 235 flashing when you set it to "Normal", you're losing nothing in the white level, and the picture looks good to you without wash-out or black crush (so it indicates the black level is set correctly). What do you worry about?

Because Normal clips Black levels. It doesn't clip White levels

The Expanded setting on Epson projectors doesn't clip white or black levels.
The Normal setting clips Black levels below 16. This makes setting Brightness with a pluge pattern like the one on the AVSHD disk hard because the bars below 16 cannot be made visible. Any informatio below 16 is GONE.

With my Epson 6100 set to Expanded, blacks are not crushed, and there are no scaling artifacts, color banding or the like. Period. Setting Brightness with a pluge pattern like the one on the AVSHD disk is simple because the bars below 16 can be made visible. All information below 16 can be made visible, and so Brightness can be set so that these below 16 bars just disappear.

If setting the Epson to Expanded meant that 16-235 was being rescaled to 0-255, then the BTB bars below 16 on the AVSHD pluge pattern would not be visible using the expanded setting.

But they are visible.


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post #10 of 30 Old 10-20-2010, 06:54 AM - Thread Starter
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Thanks, I will keep digging - I am sure most of this is due to me being a noob calibrator....

It occured to me that the washed out picture is coming from my direct tv box. So if that is outputing a 16-235 signal and the epson is set to expanded, maybe that could explain what I am seeing?
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post #11 of 30 Old 10-20-2010, 11:17 AM
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How do images from your Blu-ray player look?


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post #12 of 30 Old 05-26-2011, 03:44 PM
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Anything new about this? it's driving me nuts....
Normal is NOT normal...it clips black only....
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post #13 of 30 Old 05-26-2011, 04:26 PM
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Quote:
Originally Posted by Michael TLV View Post

Greetings

from a calibration perspective ... we want to see all the detail in the above white area so expanded needs to be set. Film is mastered out to the end ... rather subjective call to say there is nothing out there so you don't need to see it.

Regards

An earlier thread had concluded that there is no meaningful 'detail' above 235 on commercially available BDs.


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post #14 of 30 Old 05-26-2011, 04:43 PM
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There is no meaningful detail above 230 ... 225 ... 220 ... 215

I guess you get to make that call.

regards

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post #15 of 30 Old 05-26-2011, 05:14 PM
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Greetings

The problem with making an arbitrary decision that all TVs should be set to show only 235 and less is that a whole bunch of those same TV sets will have pink whites or yellow whites or worse. But that is okay because there is nothing meaningful above 235.

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post #16 of 30 Old 05-26-2011, 06:00 PM
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Quote:
Originally Posted by PlasmaPZ80U View Post


An earlier thread had concluded that there is no meaningful 'detail' above 235 on commercially available BDs.

But here's the thing, you got gamers here, movie watchers, people with htpc's....it's not as simple as just blu ray
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post #17 of 30 Old 05-26-2011, 06:33 PM
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Originally Posted by kindi_boy View Post

Anything new about this? it's driving me nuts....
Normal is NOT normal...it clips black only....

Set the Epson to EXPANDED, NOT NORMAL. Otherwise, black levels below 16 are obliterated. Trust me on this.


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post #18 of 30 Old 05-27-2011, 05:52 AM
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Personally I can only think of a couple issues that might be a problem with a display internally cutting off black and below. If your source was altering levels so that black was actually lower than typical black that would be a problem, since you wouldn't be able to adjust for it with brightness, but personally my electronics over HDMI seem to be rather consistent. I suppose setting brightness using Digital Video Essentials, or similar pluge patters, would be a bit of a guessing game. Generally these items don't seem much worse than if the display model happens not to have enough user control range for sending a video range to the display expecting a computer input.

Anyway with the AVS HD 709 or similar patterns, basically you would just set brightness too low and raise it until the above black information shows up.


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post #19 of 30 Old 05-27-2011, 10:24 AM
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Quote:
Originally Posted by Michael TLV View Post

There is no meaningful detail above 230 ... 225 ... 220 ... 215

I guess you get to make that call.

regards

http://www.avsforum.com/avs-vb/showthread.php?t=1240153

That's the thread. It's the difference between theory and actual observation/analysis.


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post #20 of 30 Old 05-27-2011, 10:27 AM
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Quote:
Originally Posted by Michael TLV View Post

Greetings

The problem with making an arbitrary decision that all TVs should be set to show only 235 and less is that a whole bunch of those same TV sets will have pink whites or yellow whites or worse. But that is okay because there is nothing meaningful above 235.

regards

No, discoloration is not something I was recommending. Simply put it's okay to clip above 235 as long as there is no discoloration or eye fatigue.


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post #21 of 30 Old 05-27-2011, 10:45 AM
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Quote:
Originally Posted by newfmp3 View Post

But here's the thing, you got gamers here, movie watchers, people with htpc's....it's not as simple as just blu ray

BDs and DVDs are reference material; most video games are not, TV programming is not, etc.


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post #22 of 30 Old 05-27-2011, 09:27 PM
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Greetings

I see a discussion about where to set wiggle room just in case ... from a guy that actually does transfers. I don't see a definitive slam the door at 235 discussion except for you saying it.

If you follow the three rules to setting contrast, you won't get into trouble. If after setting for the rules and you find that the light output is not as bright as one might like ... then looking for a way to trade off one thing for another in terms of overall importance is a way of life.

Trade off a bit of the top end and gain some light output out of it. Not that different than the discussion about using dynamic iris controls to address a deficiency in the display in question. Either way a trade off ... sacrificing one thing or another.

Within professional circles ... on the manufacturing end, the top end of the range from 247-255 has been known to be sacrificed because certain displays were not able to hit specified light output targets when adhering to the 255 top end.

I know of one effect on the white end which is not so much about hidden detail but rather using the range to create the effect of fading to white ... rather than a hard clip to white. If you set the wall at 235, the display loses the ability to show this effect that is used in films and you get the hard clip.

So I am not militant about the 254 top end ... and do see occasions where trade offs are made. I would not be so quick to dismiss the top end ...

Setting it to try to show up to 254 is still good practice ... and decisions can be made after that is achieved to account for deficiencies in other areas ...

regards

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post #23 of 30 Old 06-02-2011, 10:33 AM
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Quote:
Originally Posted by Michael TLV
Greetings

I see a discussion about where to set wiggle room just in case ... from a guy that actually does transfers. I don't see a definitive slam the door at 235 discussion except for you saying it.

If you follow the three rules to setting contrast, you won't get into trouble. If after setting for the rules and you find that the light output is not as bright as one might like ... then looking for a way to trade off one thing for another in terms of overall importance is a way of life.

Trade off a bit of the top end and gain some light output out of it. Not that different than the discussion about using dynamic iris controls to address a deficiency in the display in question. Either way a trade off ... sacrificing one thing or another.

Within professional circles ... on the manufacturing end, the top end of the range from 247-255 has been known to be sacrificed because certain displays were not able to hit specified light output targets when adhering to the 255 top end.

I know of one effect on the white end which is not so much about hidden detail but rather using the range to create the effect of fading to white ... rather than a hard clip to white. If you set the wall at 235, the display loses the ability to show this effect that is used in films and you get the hard clip.

So I am not militant about the 254 top end ... and do see occasions where trade offs are made. I would not be so quick to dismiss the top end ...

Setting it to try to show up to 254 is still good practice ... and decisions can be made after that is achieved to account for deficiencies in other areas ...

regards
Quick question, Mike. When I purchased my Epson 8350, I use the settings Art used in his review to set stuff such as gamma, color gain/bias etc. Obviously, he isn't using the same screen or room condition as my setup. This means I should go back, reset everything to factory default and calibrate from there? I'm just using the AVSHD cal suite and my 38 year old eyes.
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post #24 of 30 Old 06-02-2011, 11:03 AM
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Greetings

His settings are for his gear and screen and environment. If that is somehow the same as your stuff ... it might be a good starting place ...

Reset to factory ... go to the cinema mode and start there. If it were a THX projector ... you'd start there.

(On a whim ... I looked at 4 BD flicks to see if I could find WTW material ... and I found it on two of the films so it is not a case where films don't have material up there ... they do. Obviously on a case by case basis. On one flick, setting contrast to only 235 was like adding heavy noise reduction to the image. )

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post #25 of 30 Old 06-02-2011, 11:10 AM
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Quote:
Originally Posted by Michael TLV
Greetings

His settings are for his gear and screen and environment. If that is somehow the same as your stuff ... it might be a good starting place ...

Reset to factory ... go to the cinema mode and start there. If it were a THX projector ... you'd start there.

(On a whim ... I looked at 4 BD flicks to see if I could find WTW material ... and I found it on two of the films so it is not a case where films don't have material up there ... they do. Obviously on a case by case basis. On one flick, setting contrast to only 235 was like adding heavy noise reduction to the image. )

Regards
Ok, so on the topic of WTW. I should increase contrast until clipping occurs or until there is color shift or the first to occur of the two? BTW, what are three rules of setting contrast that you mentioned before?
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post #26 of 30 Old 06-02-2011, 11:15 AM
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Greetings

Contrast rules ...

1. No clipping (See all the way to 254-255 ... or best you can do with display)
2. No discoloration ... or color shifting. Near whites look pink or yellow or something not gray for instance.
3. Eye fatigue considerations. (Usually not a big deal when dealing with projectors since they tend to be not as bright most of the time versus too bright) Rule of thumb is ... if it hurts your eyes ... the contrast is too high. (Turn down iris first if applicable before turning contrast down.) This is not about setting it to some specific number.

regards

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post #27 of 30 Old 06-02-2011, 11:45 AM
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Quote:
Originally Posted by Michael TLV
Greetings

Contrast rules ...

1. No clipping (See all the way to 254-255 ... or best you can do with display)
2. No discoloration ... or color shifting. Near whites look pink or yellow or something not gray for instance.
3. Eye fatigue considerations. (Usually not a big deal when dealing with projectors since they tend to be not as bright most of the time versus too bright) Rule of thumb is ... if it hurts your eyes ... the contrast is too high. (Turn down iris first if applicable before turning contrast down.) This is not about setting it to some specific number.

regards
Greetings and Salutations,

Great info, thanks! :-)
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post #28 of 30 Old 06-02-2011, 03:33 PM
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Originally Posted by Michael TLV View Post

I looked at 4 BD flicks to see if I could find WTW material ... and I found it on two of the films

Please list the examples. Personally I have looked at easily over 30 commercial DVDs and Blu-rays. So far I have not yet ran across any examples where video information was clearly intended to exceed reference white. If there are really examples of commercial discs that clearly exceed reference white it would be nice to verify.


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post #29 of 30 Old 06-02-2011, 08:15 PM
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Greetings

I found it on Whiteout and Ice Age 2 ... but not on 5th Element and Vertical Limit.

Regards

Michael Chen @ The Laser Video Experience
ISF/THX/TLV Video Instructor
The Video Calibration Education Hub -
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post #30 of 30 Old 12-20-2011, 08:58 PM
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I've been searching for more on AVS about the levels on the Epson projectors, and I came across this thread.

Kilgore, I see you are promulgating this misinformation across the forums. It seems to me that Epson's "normal" HDMI range (which should equate to the HDMI spec) does not pass BTB (below 16) but does pass WTW (above 235). This is perfectly OK for a video levels source. You don't need BTB for anything. Calibration is done with a suitable pattern showing levels 16 and up, and is adjusted so that 17 is just visible. There is no video information stored below black. BUT its good to see Epson understand the need to preserve WTW, which in "normal" mode they have done.

Quote:
Originally Posted by Kilgore View Post

The Normal setting clips Black levels below 16. This makes setting Brightness with a pluge pattern like the one on the AVSHD disk hard because the bars below 16 cannot be made visible. Any informatio below 16 is GONE.


I've seen the light... and its "White 255"!! (or is it 235?)
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