View Full Version : Calibrating Monitors


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Christopher Go
February 21st, 2003, 06:29 AM
How many of you properly calibrate your CRT or LCD monitors? I understand this is a must for production monitors in the editing suite if you're lucky to have one, but what about the computer monitor itself? I believe animators, designers, and those who do work with digital photography, like Photoshop for example, should certainly look into calibrating their monitors. What about for digital video?

Ken Tanaka
February 21st, 2003, 11:39 AM
Calibrating a CRT monitor is essential if you're using it for color judgement. Video University (http://videouniversity.com/tvbars2.htm) features a good tutorial on the process.

Calibrating computer monitors for SMPTE video color accuracy is not really a worthwhile effort. Color calibration for digital illustration (i.e. Photoshop, et.al.) attempts to normalize a computer's screen to printed results, such as a particular printer's characteristics or the Pantone color system. Since printers (desktop or large scale) use a matrix of overlayed dots to form their image this calibration works very well.

But in the case of video, the standards for "printed results" are basically NTSC or PAL broadcast standards which operate in a very different color universe than your computer monitor. That's why you need to use a good CRT monitor to judge your color as you edit.

Christopher Go
February 21st, 2003, 07:45 PM
Thanks Ken, unless I'm doing extensive color correction on my CRT monitor then I won't really worry about calibrating it as I would for, say, a Sony broadcast monitor.

Bryan Roberts
April 22nd, 2003, 03:25 PM
Hey all. Well I've been editing some projects and I've noticed that they are always much darker on other people's monitors. I am lead to believe that I have my brightness turned up very high and I was curious how can I calibrate my monitor to be on the same level as others. Thanks!

Mike Rehmus
April 22nd, 2003, 04:31 PM
Almost impossible as very few people really calibrate their monitors.

If you are talking about a NTSC monitor, you can run color bars into it and adjust accordingly. A search on Google will find you colorbar files and instructions.

Computer monitors are normally darker and really cannot display video with the kind of quality normally needed to judge the video.

Ken Tanaka
April 22nd, 2003, 04:45 PM
Bryan,
Video university has a pretty good tutorial (http://videouniversity.com/tvbars2.htm) on calibrating a professional CRT monitor. There are several versions of this process but they generally arrive at the same point.

Calibrating a computer monitor is a different matter, principally because they operate on a different color space and display technology. Run a Search on this topic, as we recently had a lengthy thread on this subject.

Dan Measel
April 22nd, 2003, 07:23 PM
I used the following link.

http://www.wideopenwest.com/%7Ewvg/tutorial-menu.htm

Brad Simmons
July 16th, 2003, 09:51 PM
Hi guys. I recently purchased a brand new Sony PVM 8045Q 8" color monitor for field and post work with Ken's advice. The manual wasn't much help to me, as I'm new to all of these engineering phrases and none of them are explained in the manual.

I have a few questions. I checked out this link right here as a start. http://www.videouniversity.com/tvbars2.htm
I'm just trying to set up the monitor so it will display accurately. I've already shot all my footage (without the monitor unfortunatley), so now I'm just using it for post.

One problem I'm running into is that it tells me to adjust with the blue gun setting. I feed color bars from my XL1s into my monitor. I'm following the directions and I turn on the blue gun, but I don't get any blue, all I get is monochrome black, white, and grey. Everything else such as chroma, brightness, phase etc. has not been toyed with and is set right in the middle. Anyone have an idea why I'm not seeing blue bars? If someone could explain their typical workflow that's be great. I just want to make sure I have this thing set correctly. Thanks.

Another thing, a lot of these calibration articles talk about "hue" and say it's different from "chroma". and to adjust them separately. I see the chroma button, but son't see an adjustment for hue. Anyone know what the other possible names for hue are?

Another question I have is basic technique on calibration. I don't understand how it works...if I calibrate my monitor according to that link above, why would I ever need to calibrate it again? One post here mentions. "You have to calibrate a monitor every time you use it, in terms of putting up bars, running through blue check, adjusting color, etc."

I'm confused on why you have to do this. If you set up the color bars and they are all adjusted perfectly, then why would you want to change the setup? Also, if you have to calibrate your monitor every time you use it, why would people send in their monitors for expensive calibration, only to have to change it all next time they turn it on? Guys I'm so so confused about this thing right now, any help or advice would be appreciated.

Brad Simmons
July 16th, 2003, 11:06 PM
Actually, I just figured out Hue is aka "phase", and I think I was confused about the blue gun only setting, turns out you don't really see blue bars, just monochrome bars which are more helpful in adjusting just the chroma, am I right on that? Sorry to be a pain with so many questions...but one article advises that you calibrate adjust for shooting but..."Remember to switch your monitor back to normal before editing." http://www.greatdv.com/video/smptebars.htm

So does that mean that when I'm ready to edit my footage, no calibration is needed? That confuses me, because I thought you had to keep it the exact same as you calibrated during a shoot.

It's funny that after adjustments with the color bars, now my monitor is supposedly calibrated, yet all I've done is make some tiny adjustments to the buttons. I'm wondering why the monitors aren't factory set to have these minor adjustments already made? Ie, why isn't the proper location of the chroma button actually in the middle instead of off to the right a tad?

Jeff Donald
July 17th, 2003, 09:41 AM
Phosphors in the CRT change with age and adjustments will be necessary throughout the life of the monitor. Therefore, don't expect it to stay in calibration for long. Large CRT's are actually effected by the magnetic fields of the earth. It is sometimes difficult to calibrate monitors from the southern hemisphere in the northern hemisphere. This can be demonstrated by moving the monitor to different locations within a room.

It sounds like you figured out blue gun. Blue gun is also helpful for analyzing noise in a scene. Check out some VHS tapes then mini DV with just the blue gun. Pretty amazing.

The monitor will need to be calibrated for different ambient lighting conditions. Thus, the necessity for calibrating the monitor for field use and indoor use, editing etc. I edit with all the light off or very dim. This effects the monitor calibration as opposed to being near a window.

Does the XL1 output SMPTE color bars? I was under the impression it didn't. You might want to check that in the manual (mines not handy or I would). If you work is very color critical you need to use SMPTE bars.

Brad Simmons
July 17th, 2003, 12:33 PM
Hi Jeff, thanks for the response. Now I'm learning about IRE issues and 7.5 setup which is very confusing at first when outputting to analogue etc... but I think I'm starting to understand all this more.

I thought the XL1s had SMPTE color bars. (at least that is the pattern they display, I'm not aware if they're legal or not). Does anyone have a definitive answer on that?

Jeff Donald
July 17th, 2003, 12:42 PM
Most all the equipment should handle setup automatically. It's good to know, but you shouldn't have to change anything. If setup is needed, it will be added at the analog output by almost all devices. Exceptions are very high-end decks (it can be disabled) and a few very old decks.

Rob Lohman
July 25th, 2003, 02:45 AM
The "old" XL1 DOES NOT have compliant bars. The NEW XL1s
DOES!

Dan Lahav
November 8th, 2003, 03:01 AM
How do I go about calibrating my professional monitor to achieve the best color? I currently cannot hook up my computer to my monitor unfortunately so no color bars...I have my DVD player hooked up via s-video at the moment and access to a DVD burner...i dont know if this helps. Thanks.

Josh Bass
May 23rd, 2004, 12:21 AM
Ok, I know how to calibrate a monitor using your typical SEMPTE bars, but what about other kinds? I mean specifically those bars that don't have a pluge, where it's just a series of vertical lines all the way across the screen. Any instructions for those, anywhere?

Ken Tanaka
May 23rd, 2004, 12:25 AM
"Those other bars" could be anything. The value of SMPTE bars is that each area consists of specific chrominance and luminance values. So if there're no reference values you cannot have true calibration, by definition.

Josh Bass
May 23rd, 2004, 07:44 AM
True, but aren't there "legit" bars that have that pattern? I see them at the beginning of agency tapes sometimes. . .doesn't seem like a production company would be using fake bars.

Robin Davies-Rollinson
May 23rd, 2004, 08:18 AM
I think you must be talking about EBU (European Broadcasting Union) bars. Thery are our standard bars and we line them up to a vectorscope where we can see the chroma level and also if the chroma phasing has to be rotated to correct or not.
Just as standard here as are yours accross the Pond ;-)

Robin.

Josh Bass
May 23rd, 2004, 09:09 AM
Makes sense. However, I'm not usually (or, heck, ever) able to use a waveform monitor and vector scope. I was just wondering if there was some method by which people calibrate their monitors to these bars.

Jeff Donald
May 23rd, 2004, 09:15 AM
You can only calibrate a monitor to a known accurate source for the bars. Calibrating a monitor to bars off a tape is of almost no use. You would need a scope and proc. amp etc to verify the bars and correct them if needed.

Josh Bass
May 23rd, 2004, 03:33 PM
Sorry, let me clarify. I didn't mean to imply that I was trying to calibrate to taped bars. Some lower-end cameras generate this style of bars. I figure, though it may not be perfectly accurate, wouldn't calibrating the monitor at least give you SOME idea of what you're actually getting? I used a lower end Sony cam a few weeks ago (TRV950, I think. . .little tiny thing) and it had that style of bars.

Jeff Donald
May 23rd, 2004, 05:25 PM
It is almost impossible to adjust for the NTSC requirement of set-up with the pluge in the color bars. PAL doesn't have set-up so no pluge in their bars. Phase can be set by using a blue filter and adjusting the bars to match grey levels. Not easy to explain, sorry. But it is all a waste of time if the bars are off.

Josh Bass
May 23rd, 2004, 07:56 PM
Okay, well, then I guess that's the way it is. Thanks anyway, guys.

Sean McHenry
May 27th, 2004, 07:19 PM
Well, don't let all this discourage you too much. There are ways to calibrate most monitors, and even Televisions with color adjustments for RG and B if they are on separate controls.

You will need a way to get an accurate color bar image to the screen. If you use a laptop or PC and call up some of the preset color bar images, or use a Calibar or Calibug, you can convert your VGA output to composite or S-Video with the correct devices (scan converters). Or, if your monitor has RGB inputs, they make a special "breakout" cable that connects to your 15-pin VGA and has 3-5 BNC connectors or RCA connectors. Plug that into your input.

There are directions on more professional sites about how to actually do the corrections.

There is even a way to simulate a "Blue Only" function by using a deep blue gel in front of the screen. You'll read about Blue Only on the other sites.

I know it's not 100% accurate, especially if you use converters but it's better than nothing.

Good Luck,

Sean McHenry

Josh Bass
May 28th, 2004, 03:25 AM
Thanks. Keep in mind, the problem was with the bar source, not the monitor. I'd need a bar source in the field.

Sean McHenry
May 28th, 2004, 06:22 AM
Ah. In that case, look into the Calibug. I have not used it but I believe it is basically a USB drive with various images on it with the test patterns you can use with a laptop or other PC like device that has an S-Video output.

Also look for the Newtek (Yep, the 3D software folks) Calibar. It was the size of a large pen and had a BNC on the end of it. Push the button(s) and get test patterns out of it. Great idea really. Small enough to carry everywhere but a bit pricey. I am not sure it is even around anymore. The Calibug is also made by the Newtek folks I believe.

Google for it. It's out there.

Sean

Josh Bass
May 28th, 2004, 11:17 AM
Ok, those sound like good solutions. However, I don't have a laptop. Is there something that just plugs right into a monitor?

Sean McHenry
May 28th, 2004, 09:22 PM
Yes, look at sites like Markertek and TecNec (really the same company) - Sorry Boyd. B&H likely has them too but I know the others do. Maybe get the products from those sites and see if B&H has them.

If you really get stuck to find something, let me know and I'll work with you through my place. Sponsored by B&H or not, if they don't have it, you should look elsewhere for what you need.

Do a search on the sites for Bars Generators or Color Bars, etc.

Sean

<<<-- Originally posted by Josh Bass : Ok, those sound like good solutions. However, I don't have a laptop. Is there something that just plugs right into a monitor? -->>>

Josh Bass
May 28th, 2004, 10:55 PM
thanks.

Dwight Flynn
July 21st, 2004, 10:15 PM
How do I go about determining if my jvc tm-h1375su ntsc/pal monitor is calibrated correctly?

Thanks

Glenn Chan
July 22nd, 2004, 09:44 AM
http://www.videouniversity.com/tvbars2.htm

Tony Pham
March 10th, 2005, 05:17 PM
Hi everyone,
I've just got the Sony PVM 14L2 monitor and tried to calibrate the monitor using the instruction on this website:

http://www.indianapolisfilm.net/article.php?story=20040117004721902

I've got to the very last part, but then I couldn't adjust the Hue to get the result like the last picture on that site. I got pretty close to it, except I couldn't see the little blue bar at the bottom right, no matter what I try. So, I ignored it and went on to editing.

But then I realized that the picture on my TV (which is looped through the PVM 14L2, which is connected to my VCR. And the VCR is connected to my little digital camera connected to the computer via firewire) is really bad compared to what is on the PVM 14L2. I'm saying this because I've got a closeup shot of a girl and her skin isn't very soft. However, when I look on my PVM, her skin doesn't look as bad as it is on the TV. This is really weird because if I base my color correcting on the PVM, then when people watch it at their home, the image's gonna be really bad. Isn't the picture on the PVM suppposed to be "truer" than it is on TV? Please advice. Maybe I did something wrong in calibrating my monitor?

Wayne Orr
March 10th, 2005, 09:42 PM
Sorry, Tony, but your grammar has me a bit confused. Anyway, here is a link to Syntetic Aperture, where they have an excellent download on monitor set-up: http://www.synthetic-ap.com/tips/calibrate.pdf
They also have accurate color bars you can download for FREE.

Wayne Orr, SOC

Tony Pham
March 10th, 2005, 10:40 PM
Thanks Wayne for the link and excuse my English. But can you let me know which part confused you? Thanks.

Wayne Orr
March 11th, 2005, 11:25 AM
"But then I realized that the picture on my TV (which is looped through the PVM 14L2, which is connected to my VCR. And the VCR is connected to my little digital camera connected to the computer via firewire) is really bad compared to what is on the PVM 14L2."

What is "really bad," Tony? The camera, vcr, or the picture on the TV? If the picture on the TV is really bad, why are you using it?

Hopefully you have the monitor connected to the S-video of the camera. That would be best.

" I'm saying this because I've got a closeup shot of a girl and her skin isn't very soft. However, when I look on my PVM, her skin doesn't look as bad as it is on the TV. " ????? On the front of the monitor, there should be a control for "sharpness" or some such. Be sure that is in the detent, or about mid-range.
Also, check for a similar setting on the TV controls, and be certain it is set mid-range. "Sharpness" is not a function of normal monitor set-ups. If your monitor is set correctly, I would not pay too much attention to the TV. And hopefully you are using SMPTE split field bars for your set-up. Yes? They are included in that FREE app from Sythetic Ap.

Wayne

Tony Pham
March 11th, 2005, 02:36 PM
I'm sorry, Wayne. Let's me try to explain the problem one more time.

I preview my work on the Sony PVM using firewire connected to my little camera Sony DSR-38. I also use the output in my PVM to get the picture on the standard TV. So now I have 2 monitors (my Sony PVM and the standard TV) connected to the same source. This is where the problem begins. The image on my sony PVM is a little softer than the image on the standard TV. For example, I have a CU of a girl on both monitors. On the PVM, her skin is a little softer, and it's really hard to see any wrinkles on her face. However, on the standard TV, her skin looks sharper, and I can see all the wrinkles clearly. Can you explain this? Thanks.

By the way, I did reset all the settings on my standard TV and put the sharpness to the midrange. I also calibrate my monitor using the SMPTE color bars.

One more thing, someone once told me that my problem might be related to the black level my little camera output and that getting a DV transcoder with the add setup might solve my problem. What do you think about this? Thanks.

Hope it makes sense this time.

Wayne Orr
March 11th, 2005, 08:43 PM
OK, Tony, now I get it. However, I'm afraid I don't have a good explanation for what is happening here, except that often TV sets have the sharpness turned up quite high at the factory, so you don't notice as they begin to die with old age. This, of course, assumes that your pro monitor is in good working order. Have you used it before, and know it to be accurate, or did you just purchase it recently? Does it look sharp on other material with fine detail? You can get find a resolution chart on the web with instructions for using it to see if your monitor is resolving as it should be.

The other way to go would be to lay off to tape the material you are concerned about and play it back on a friend's TV that you feel is in good working order.

Sorry I can't be more helpful.

Hugh DiMauro
March 15th, 2005, 09:01 AM
How do I set up a location monitor without color bars/pluge pattern since my Sony PD 170 doesn't have the pluge pattern to correctly set up brightness and contrast?

Glenn Chan
March 15th, 2005, 01:19 PM
From your editing program, record bars and tone (with pluge bars) onto DV tape.

Most programs give you correct bars... double check on the scopes in your editing program.

Boyd Ostroff
March 15th, 2005, 02:06 PM
You could also burn them to a memory stick on your PD 170. They would be scaled down to 640x480 but that shouldn't matter a lot for what you want....

Doing it on tape is a good idea too - have done that myself. Only problem is you need to remember to put them on all your tapes, or you have to swap tapes, etc.

Hugh DiMauro
March 15th, 2005, 04:18 PM
Boyd? Glen? Why in hell didn't I think of that? May I say that you two guys are my new heroes? I am calling Rick Bravo right now and telling him that he's no longer my hero. You two knocked him out of the box.

For shame, Rick Bravo! Not answering my call for help! Harummph!

One more question: Does Vegas 5 have true SMPTE color bars? That's what I use. Also, how do I double check the color bars/pluge pattern on my scopes?

Glenn Chan
March 16th, 2005, 12:10 AM
Hmm maybe it isn't worth it to check color bars on scopes. Vegas 5 does have proper SMPTE color bars. To setup the scopes properly:
Click on the "Scope Settings" button (in the video scopes window) and check both "7.5IRE Setup" and "Studio RGB (16 to 235)" for North American NTSC DV; japan is different). Read the manual if you're unclear on what settings to use.

Once you have the video scopes setup properly, the pluge bars should read "3.5", "7.5", and "11.5". Vegas doesn't give precise values like that on the scopes but you get the point.

If you have faith that the bars are right (like I do), then just do it. Checking on scopes just adds complication and you may not even be sure they are right.

This information does not apply to Vegas 4 and before.

2- Hopefully this doesn't confuse you more:
When you calibrate the monitor to your PD170 you may want to watch out for the 7.5IRE setup issue. DV digital values range from 0-255, and the blackest black is supposed to be 16 (not 0). 16 (digital) is supposed to translate to 7.5IRE (analog) during the digital--> analog conversion. Some equipment puts 16 (digital) at 0IRE which is improper. Your PD170 may do this, or it may have a setting to switch between 0 and 7.5IRE.

If you are calibrating before you shoot then this isn't an issue at all (you can say your blackest blacks are at 0IRE, 7.5IRE, or anything else you'd like). If you would like to avoid giving problems to the people who will use the equipment next, then leave a note or something saying they should re-calibrate the monitor.

Tony Pham
March 19th, 2005, 02:35 AM
Thanks Wayne, it's a brand new monitor from B&H. The last option is okay, although that would kill the point of having NTSC monitor.

Ian Stark
March 19th, 2005, 06:30 AM
Hi all,

Looks like there aren't too many people using the JVC TM-90PSN monitor! (see http://www.dvinfo.net/conf/showthread.php?s=&threadid=41281).

I was given mine second hand with no user guide.

I guess that many of the switches are common to other monitors. I wonder if anyone could explain what the following switches are for and when they should be used:

SKEW (on / off)
DISC SW (auto / 50Hz)
75ohm SWITCHED OUT/OPEN BRIDGE OUT

Regarding calibration, I can display PAL colour bars on the monitor through my XM2, but what do I calibrate against? Is it just done by eye? I understand there are various calibration devices and scopes available but in the absence of these, is there an alternative method?

Any advice welcomed with open arms. Thanks.

Ian . . .

Glenn Chan
March 19th, 2005, 11:32 PM
75ohm SWITCHED OUT/OPEN BRIDGE OUT

I believe this is what happens:
If you want to daisy-chain monitors, then by taking 75 ohm resistance out you will be able to daisy-chain without weaker signal strength.

Not too sure what the two other functions are.

2- Monitor calibration:

The following two links have some information on this, although they apply more to NTSC/North America:
http://www.videouniversity.com/tvbars2.htm

http://www.synthetic-ap.com/tips/calibrate.pdf (PDF)
http://www.synthetic-ap.com/tips/index.html

I find that even if you calibrate your monitor to color bars, the colors can still be whacked. Monitors shift colors as they age, and room lighting conditions can affect your eye's white balance and there can be glare on the screen (block light with your hands to test that).

*some monitors have a feature in their menu which lets you feed color bars to it and it will auto-calibrate itself. I don't know if this works with PAL.

Andre De Clercq
March 20th, 2005, 04:43 AM
1.Feed through setting has been covered by Glen. Daisy chaining monitors is not allways adviseable because most feed through filters introduce some image quality reduction.
2.Skew: a geometry setting to make the active image borders parallel to the display bezel (after keystone correction)
3.Are you shure it's "DISC SW"and not "DISP SW". The latter means switching the 50/60 Hz auto detection on or off.

Ian Stark
March 20th, 2005, 05:35 AM
Thanks, gents, for your responses.

Andre, definitely DISC.

Glenn, yes, I followed the instructions there. My monitor doesn't have an autocalibrate facility (it's fairly basic) but I have done what I think it is a reasonable job. I guess I need to find someone with some scopes to really do a good job though.

Thanks again for the help.

Ian . . .

Chris Bottrell
April 18th, 2006, 12:05 PM
Hi All,

I use a Canon XL2 and have just bought a Sony PVM 1440 Monitor, now the question is do i calibrate the monitor to the camera or to my NLE system or both? (i use premiere pro and after effects)

I am using a Geforce 6500 graphics card with the ability to change the colour profile do i leave this as standard or choose say STMP-C or Adobe 1998 or what?

The other way i thought is to attach the XL2 to the monitor and calibrate the monitor with the XL2 colour bars, then fine tune it with my eye to make sure all colour look correct to what i see with the naked eye? I have tried using the instructions on videouniversity but i cant get my monitor to display three grey bars down the bottom right.

Please help

PS all my equipment is PAL!!!

Glenn Chan
April 29th, 2006, 02:17 AM
What editing system are you using?

Generally speaking, only use the color bars generated from your NLE. Don't import pictures, the levels can be wrong.

hook up your XL2 via FIREWIRE (not S-video off the video card) and attach the monitor to the XL2.

Then use the instructions from video university.

2- If the XL2 has "7.5% setup" like the XL1 does, you should probably disable it (it should be disabled/off by default). It may be adding digital setup- I would only turn it on if you know what it does.

Jack Walker
July 26th, 2006, 08:27 PM
I read a post from someone who used a piece of hardware to calibrate TVs to use as monitors. I visited the website but can't find it again.

The company makes a triangular looking device that sits on the monitor/TV (there are a couple of models) for calibrating the monitor. The devices cost in the area of $200.

I think I saw it in this forum, but can't find it now. Can someome please point me to it? Thank you! I think it might have been one of the main moderators who made the post. I want to find it soon, because there was a sale that ends the end of July.