Jump to content



Sign up for a free account!

Signing up for an account is fast and free. As a member you can join in the conversation, enter contests to win things like this Logitech Harmony Ultimate Remote and you won't get the popup ads that guests get. Click here to create your free account.

Photo
- - - - -

What is ISF callibration?


This topic has been archived. This means that you cannot reply to this topic.
5 replies to this topic

#1 of 6 ToddP

ToddP

    Stunt Coordinator

  • 172 posts
  • Join Date: Sep 15 2003

Posted September 15 2003 - 09:00 AM

I currently have a Video Essentials disc that I use to calibrate my own TVs, and anyone in my family who will let me (they all complain that I make the picture too dark). I feel like it has done a phenominal job improving the picture quality on all of my sets. I'm new to the forum (this is my first post), and am finding lots of interesting information here. One thing I'm curious about though, is this ISF callibration that I keep seeing people reference. I think I am 2 days away from purchasing a Pioneer Elite PRO-630HD, and figured that I would just pop in my Video Essentials and set things up. However, with all these references to ISF callibration, I'm wondering if I should be doing more. Thanks in advance for the help.

#2 of 6 Jack Briggs

Jack Briggs

    Executive Producer

  • 16,725 posts
  • Join Date: Jun 03 1999

Posted September 15 2003 - 09:30 AM

ISF = "Imaging Science Foundation"

It's a certifying organization founded by Joel Silver that seeks to establish a uniform, high-quality standard for monitors/TVs. The "ISF calibration" you keep seeing referenced means that a tech who has been trained and certified by the ISF has calibrated a set's grayscale and other performance parameters. Two of Home Theater Forum's moderators, Gregg Loewen and Michael TLV, are ISF-certified calibrationists.

Imaging Science Foundation

#3 of 6 ToddP

ToddP

    Stunt Coordinator

  • 172 posts
  • Join Date: Sep 15 2003

Posted September 16 2003 - 03:57 AM

What kind of cost should one expect to incur with something like this? Also, is it something that I should absolutely have done to a new tv, above and beyond my own Video Essentials calibration?

Another question I have is how different is the new Digital Video Essentials from the previous version? Is the old copy enough, or should I pick up the new one?

#4 of 6 Jack Briggs

Jack Briggs

    Executive Producer

  • 16,725 posts
  • Join Date: Jun 03 1999

Posted September 16 2003 - 04:04 AM

As good as Video Essentials is, it only enables you to dial in a decent picture from the user controls/menus. An ISF calibrationist goes much further, using a color analyzer to correct a set's grayscale tracking from within the service menu. He also cleans the CRT lenses and adjusts the focus. And this is just part of the regimen. The result is a set that performs to its fullest capability.

Costs for a complete calibration vary, depending on the size and complexity of the set. You can spend hundreds on a complete calibration, but it's worth it.

#5 of 6 Robert_J

Robert_J

    Lead Actor

  • 8,059 posts
  • Join Date: Aug 22 2000
  • Real Name:Robert
  • LocationMississippi

Posted September 16 2003 - 05:00 AM

To get an idea of what's involved, here's an part of an e-mail from Craig Miller (Mitsubishi calibrator). He charges a flat fee of $750 for a calibration.

-Robert


A full scale Mits calibration takes approximately 10-14 hours and includes the following:

1. First Inspection. Using various Avia and HD Generator test patterns I inspect the screens, CRTs and other items on your set. There is no sense in calibrating it if you are going to need any repair work. Also at this time we look at Component 480i as verses S-Video if you have an interlaced DVD player. Since Component 480i has a number of differences that effect other calibrations and tweaks we need to agree on which hook up you will be using. At this time we also talk about the protective screen and remove it if you would like. At this point I'll have a good idea on how much improvement you'll see from the calibration. 98% of the sets see a very nice improvement in image clarity, color, geometry and convergence. If I feel that you will not see that much improvement I'll let you know so you can decide if you want to go forward with a full up calibration or if you would be better off just correcting a few items and save some $$.

2. Next we open it up and continue the inspection: Mirror condition, Lenses, and check for CRT coolant leaks. If all of that looks good, the lenses are removed and the actual CRTs, coolant and coolant lenses are inspected for any anomalies.

3. If everything passes we move on to cleaning. Cleaning is a very important step in the calibration. Even though these are relatively "new" sets, they all need a very good cleaning. This really helps improve the picture clarity.

4. Clean the Mirror. This usually take 3 to 4 passes to get the factory "film", smudges and finger prints off. The 73" set with the Mylar mirror should never be cleaned only dusted lightly with air.

5. Give the lens assemblies a careful but very good cleaning. We also remove that nasty tape at this time and replace it with new tape after focus is complete.

6. The coolant lenses are cleaned next. These coolant lenses or covers are very concave and collect a lot of dirt and bug parts at the factory.

7. And then the Screen Assembly is cleaned. It is amazing how dirty many of the fresnel lenses are (inside back of the screen). This shows up as dark streaks in a 100 IRE (White) Field.

8. Then I hook up my black box (I2C Interface) and download and archive all of the current User menu and Service menu settings for your set.

9. G2 Voltage (Screen VRs) is next. I set these at factory specification +- .1 volt. This determines the base level for all of the following adjustments and it may improve CRT life. This also helps the AKB (Auto Cathode Balance) work properly which helps hold the grayscale adjustment as the CRTs age. These are set incorrectly on just about every Mits. A little too high or low isn't that bad it's the spread between the three CRTs, upwards of 15 volts from the factory, that needs to be corrected to get the best grayscale and AKB working properly. The factory spec calls out for +- 1 volt, not the 5-15 volts that I regularly see. Also if G2 is set to high or low it hurts horizontal resolution and softens the picture a little.

10. Electrostatic and Manual focus, a very necessary and key element to a super image. Some models of the newer Mits have astigmatism correction (Quad Field Focus), so this will also be checked and adjusted to allow for optimum focus. 99.9% of the new sets with Quad Field Focus have been set wrong from the factory and this hurts corner and edge focus. I check and re-check each CRT multiple times to make sure they are at the best possible focus across the entire screen.

11. Lots of Geometry work to get the Green Grid and Overscan set properly. This is done for both SD and HD using Mylar grid overlays, actual external grid images and special scrolling test patterns to cross check horizontal and vertical linearity. Since I don't just eyeball geometry, this adds a lot of time to the calibrations. I have found that it's best to zero out the Mits factory settings on every RPTV and then set magnetic centering and yoke rotation for green and then do the geometry from the ground up. This isn't just for correcting speed bumps and uneven geometry, that can easily be done by eye. This really improves convergence which improves picture clarity, otherwise I wouldn't spend this much time, and your $$ on this step and the next step.

12. Service Level Convergence for both SD and HD. I zero out SD and HD Fine Red and Blue, set Coarse Red and Blue to starting default values, check and set their magnetic centering and yoke rotation and then re-do convergence from the ground up. This is the only way to do convergence, the Mits factory settings leave a lot to be desired and many times make it impossible to get a real good convergence across the entire screen. The Mits Red and Blue grids are pretty good but they are not exact so I use grid "images" from Avia and the HD generator to converge with. This assures that your actual image will be properly converged. Convergence is done with binoculars so that it is fully optimized from "Your Viewing Position". This eliminates the Parallax Convergence Errors that occur when convergence is done up close to the screen. Once again, I take a lot of extra care here. This is a very important step in getting the best clarity from your Home Theater..

13. Check and adjust edge enhancement through the black box for NTSC, 480p and HD modes. This removes some more of the Mits Showroom add-ons and gets us back to the true Home Theater look.

14. Check and adjust SVM and Sharpness for NTSC, 480p and HD modes.

15. Just about everything up to this point is done to improve clarity, everything that follows is to improve color.

16. Properly set the color decoder for NTSC, 480p and HD modes to remove "Red Push" on ALL inputs. No more attenuators. Besides correcting Red Saturation this also corrects Red Hue, Green Saturation and Green Hue so this also fixes the HD 1080i color decoder problems.

17. At this time the user controls will be centered except for Contrast and Brightness. These settings will be determined during grayscale calibration.

18. Check and adjust Gamma for NTSC, 480p and HD modes.

19. Set 480p grayscale, Contrast and Brightness and make them as linear as possible across the entire IRE range. And then check them against other test patterns and on actual images. Along with everything else, this is another step that I put extra work and care into for the best possible color reproduction from 0 IRE to 100 IRE

20. Set HD 1080i Grayscale.

21. And set grayscale for the NTSC inputs (Coax, Composite, S-Video, Component 480i). The Mits allows High Color Temp grayscale to be set independently for each of the three main display modes (NTSC, 480p and HD) which is very nice since they need to be set separately. The grayscale does vary between NTSC, 480p and HD.

22. Save all of the newly calibrated and tweak settings through the black box.

23. Put it all back together, wipe it all down to get my finger prints off, and then view some DVD and HD scenes to make sure you are truly 100% happy.

I use a Colorimeter for setting all of the grayscale modes/inputs and an HD Generator for setting High Definition Overscan, Geometry, SVM, Sharpness, Color Decoder and Grayscale settings.

Since it takes approximately 10-14 hours to do all of this I like to start the calibration around 9:00 or 10:00 A.M. (depending on sunset) so I can complete it before Midnight rolls around.

To do all of the above tweaks and calibrations I have a flat fee of $750. No surprises, no extra charges and no added fees per input, mode or signal type. Just one all inclusive fee.

Duvetyne ......... improves the blacks and shadow detail it also improves color saturation. To install Duve adds about 1.5 - 2 hours to the job. It would be great if you could do this prior to calibration, it's really not very hard to do, just time consuming. If you are nervous about doing it We would be happy to add it to the calibration. You buy the Duve and let's say $100 for us to install it. But, there are a number of posts here on the SPot that can help you with this so you can save a few $ here. If we install the Duve, it is done right after inspection and before the cleaning starts.

It is absolutely best if you let your set break in for approx. 3 months before calibrating it. The phosphors are a little hot out of the box and 3 months lets them mellow out a little. 3 months also gives the other electronics in the set a good chance to break in to make sure that nothing is going to fail. The CRTs change a lot in the first 300-400 hours so giving them a little time to break-in will definitely help hold your calibration longer.

I have spent thousands of hours analyzing the Mits HD sets and I believe these tweaks and calibrations are the base requirements to get the most from your set.

It makes no sense to have your grayscale calibrated if you don't have the color decoder corrected. It is almost useless to do electrostatic focus without doing manual focus and there's no reason to do focus if you are not going to thoroughly clean ALL of the optics. Edge Enhancement impacts SVM and Sharpness. Gamma impacts Grayscale, Contrast and Brightness. Geometry impacts convergence. Convergence has a major impact on the final image, etc. etc. So, IMHO there is only one way to do a Mits HDTV 100% right. To me, it's not just another RPTV, it's your "Home Theater".

If you have any questions please contact us at (909) 519-2090 cell.
I don't think that anyone else in the calibration business is as thorough as this at anywhere near this cost. Most other calibrators just do grayscale and maybe a quick touch up of geometry/convergence (at extra costs of course). Also we do not charge travel fees.

Thanks !

Craig and Sue Miller

#6 of 6 Greg_R

Greg_R

    Screenwriter

  • 1,997 posts
  • Join Date: Apr 09 2000
  • Real Name:Greg
  • LocationPortland, OR

Posted September 16 2003 - 06:05 AM

ISF certification demonstrates that a person has the basic knowledge of how to perform a calibration. You should find an expert on your display who has good references (in addition to the ISF cert).

As evidenced above, many things are possible during a calibration session. Make sure you know what you are getting when comparing costs.

There are some tweaks you can do yourself that will result in large improvements. Lining the interior with Duvetyne (and building a shadow box), disabling SVM, cleaning the optics (make sure you know what you are doing), & removing the protective screen (a tradeoff) all result in noticeable improvements. The other major tweak is to build masks for each aspect ratio (to hang on the front of the set). This results in a major improvement of perceived contrast.