Ursa's "Guide to Basic Display Calibration for New Users" - a MUST read!! - Page 2

Larry - Thanks! Actually, it sort of is a sticky, but the calibration FAQ thread does miss the discussion here.

Later,
Bill

Hello, I just read your write up and had a couple questions. I'm just getting started with this and have been doing some of what you said on my own with the THX disk. I have been adjusting the cuts and drives dialing in a way better picture. I have a RPTV and should I be starting with the main contrast and brightness at 50% or at least should they both be matching? What about the cool, standard, warm?

About the gamma I can't really do anything with that without some sort of meter can I? When making adjustments to that I can't tell what is happening. My sets values are in hexadecimal and when increasing I see the light going up but then it jumps back down again and vise versa.

I really like the colors right now but the gamma is still eluding me on what it is set on. Does it go to a certain point then reset even though you keep increasing the value?

Thanks

Grab AVIA, DVE or GetGray to find the patterns you need to properly set contrast and balance. Chris Wiggles has a write-up that gives a pretty good summary of what you need to do here. Check the calibration FAQ (sticky) for more info.


For this, you will need to find someone who has your set to give you the appropriate settings (preferrably after a full calibration), or a measurement instrument.


Each display has its own quirks when it comes to various controls, and you do need a meter (or a pro with one) to really see what some of the more advanced controls are doing. If I understand what you are saying, it definitely sounds like your set is "weird" to put it technically.

Later,
Bill

Bill,

I made the comments "before" I read the thing. Man, Bill....you have such a great way of explaining a very dry topic. You actually made if funny and interesting!!!!!

You should contact datavision and write the guides or have them pay you for this guide.

If you come out with a book or longer guide I would be more then happy to pay for it. It really cleared up somethings and yes I will most likely have some questions in the future.

You really did do a great job with this....

Just to let you know....this Calibration forum has some of the most helpful and nicest people in all the AVS forums etc. I can't tell you how many people go out of their way to help even thoughs with competing software and hardware etc......you all know who you are and I am very greatful.

Larry

Thanks man. I just bought the DVE at Overstock. Can't wait until it gets here. I love this site. I look on the web for a reason my TV has the later defined to me as "Red Push" and end up getting a better picture out of my TV than I ever could of without running into the forum......

And ended up with a brand new 5.1 system as well

Thank you for the link.

Hi Bill, I've tried to down your "Guide to Basic Display Callibration for New Users" but seems to hit some problems with "Damaged file". Can you point me to another link for download?

Try my website, www.calman.tv. It will be in the "Is CalMAN right for me?" section.

Bill

Hi Bill, thanks. Got it.

This is truly an amazing document. Great work

When calibrating grayscale where should you place the spyder2 sensor?

1. Near the screen aiming the screen;
2. Near the screen aiming the projector;
3. Near the projector

Colorfacts recommends option 1 with the spyder2 colorimeter but I think it reduces the sensor accuracy at low IRE levels. On the other hand aiming at the projector, disregards the offset (if any) produced by the screen surface (but suffers from less contaminations produced by ambient light???).

So, which method is better for the spyder2 sensor?

NS

1 & 3 are your best bets for FP use, and it depends upon what software, etc., you are using as to what makes sense. #1 is the technically accurate method, but suffers at low stimulus levels from a lack of photons to make the measurements work. #3 ignores the screen, so that can be especially irritating for folks using non-matte white screens. I hate to say it, but there really is not a "good" answer that works for all people in all cases. My guess is that most professionals use a screen offset and measure direct.

Later,
Bill

Thanks for the answer, Bill.

When you say that "most professionals use the screen offset and measure direct" does this mean they take readings from the screen and then do the calibration with the sensor near the projector (#3) or near the screen (#2)?

How do you determine the offset? Is it enough one IRE window or field (eg 80IRE) and use the difference in x and y between the two measurements and apply to all readings?

NS

This depends upon the individual calibrator and the projector in question. A Sony Ruby would require the meter be reasonably close to the projector. My Optoma H77 on a fresh bulb has a black level that is easily measured at my screen. In other words, it depends.


That is the way it is typically done.

Bill

Spyder has very bad accuracy for measurment at low light levels. IMHO, using (1) at low IRE values you'll get almost useless data.

Try to measure more then one time and you'll se that every measurement will yield different results from previous ones.

You get a lot better stability with its measurements if you increase the read time. However, discussing the merits of the Spyder2 is off-topic for this thread.

Thank you for your inputs. Based on your experience, which minimum requirements in fL would be necessary for acurate readings?

NS

This also is probably deserving of its own thread (or we can resurrect one from the past). I get fairly stable results using a 9 second read time down to about 0.2 cd/m^2 or about 0.07 ftL. If you go below that, you will want to increase the read time.

Difference, please?

thx



bob

Easy..

Think of it this way..

You can have Green tracking 6500K, then you can have Blue tracking 7500K and then have Red tracking at 5500K, the average of the 3 is 6500K..
Instead you want all three to track to it, so the coordinates will be x=.3129 and y = .329, this equals D65

ultimately, there are many ways to get to 6500K, there is only ONE way to get D65 (which will also get you to 6500K)

Thanks,

Does the HCFR software use D65? That, and the DisplayLT(sp) sensor is what I will be attempting to calibrate my new Panny 9UK plasma with.

thx

bob

yes, you can set HCFR to target D65 as well as other standard illuminants.

The question is whether the HCFR folks appropriately adjust the XYZ->RGB conversion matrices when using something other than D65. If they do not, then they are introducing error.

I have spydertv and I have windows vista, I cannot access the secret /support menu with vista how do i overcome this

I have spydertv and I have windows vista, I cannot access the secret /support menu with vista how do i overcome this

With the software available today, why would you want to do so?