[nelson4u]

I have an Optoma H79 projector used with a Lumagen Vision HDP video processor and a Denon 3910 Dvd player.


I want to calibrate the system using Digital Video Essentials and AVIA discs. I am confused where to start as the Lumagen has many test patterns built into it.


Should I calibrate just the projector first straight from the dvd player without the Lumagen in the system and then calibrate again with the Lumagen in the system ?


Should all adjustments be made in the projector user and service menus, or do I adjust the dvd player and Lumagen settings first and then make all final adjustments in the projector since it is the last component in the chain ?

 

[TomHuffman]

You calibrate the entire system. DVD players can impart their own characteristics to the chain (especially black level). The problem is how to calibrate sources for you have no test patterns? Broadcast TV and and HD DVD players are a good example. Calibrators generally use signal generators for these

 

[TomHuffman]

You calibrate the entire system. DVD players can impart their own characteristics to the chain (especially black level). The problem is how to calibrate sources for you have no test patterns? Broadcast TV and and HD DVD players are a good example. Calibrators generally use signal generators for these. You can use the Lumagen to set different levels for different sources.

 

[Joelc]

FWIW, here is what I did (with help from a calibrator):


1. Calibrate the projector from the projector -- brightness, colour, contrast, gray scale, sharpness and hue -- to get as close to optimal performance as you can.


2. Calibrate the projector from the scaler -- that is, use the scaler as a fine tune adjustment for each connection from the scaler to the projector. Of particular note for the Lumagen is the use of (i) 11 point grayscale calibration feature and (ii) copy command that enables copying results from one input to another. Not that each input (i.e. IN1A) has within it separate memories for diffferent input resolutions and aspect ratios -- this will take time.


3. Calibrate the projector per input source...that is, use the scaler's adjusment to further tweak based each source....dvd is easy due to the existence of test disk, other sources or more problematic with a signal generator the best workaround.


Hope the above helps.


Joel

 

[Bear5k]

Agreed with Tom that you calibrate the entire chain. I think Joel has some typos, but his flow is reasonable from my interpolation about how you accomplish it in detail.

With the Lumagen in the chain and if you are driving the projector with a digital connection from the Lumagen:


1) Calibrate the projector using the internal test patterns from the Lumagen (use video levels in and out). Use AVIA/DVE to set the master brightness and contrast first, though. Make changes using the controls available in the projector. This should make the projector neutral (accurate) with respect to the processor.


2) Calibrate the chain from the Denon to the processor. Here is where the controls in the Lumagen can help smooth any bumps that the Denon might have (let's hope there aren't any). To the extent possible, you will want to feed the Lumagen with component video since it mimics a higher bit-depth than digital RGB.


3) Apply the parametric changes sparingly. Once you hit 8-bit video, there is not a lot of bits there to make changes without introducing artifacts like banding.


If you are using an analog connection anywhere in here, then throw this out the door and calibrate from the DVD player to the projector only. It also helps if your calibration software can talk to your VP.

Bill

 

[nelson4u]

Thanks everyone for the taking the time to explain this. It is making a lot more sense now, however I still have a few questions.


Bill- You said to calibrate the projector first using the internal Lumagen test patterns, but you also said to set master brightness and contrast with Avia first.


Are you saying to use Avia first on all the controls that I can adjust in the projector and then use the Lumagen internal test patterns after that ?


You also said to hook the Denon 3910 to the Lumagen by component video rather than DVI. Can you explain why this is better ?


Thanks again for all the help.

 

[Bear5k]



Quote:
Originally Posted by nelson4u /forum/post/0


Bill- You said to calibrate the projector first using the internal Lumagen test patterns, but you also said to set master brightness and contrast with Avia first.


Are you saying to use Avia first on all the controls that I can adjust in the projector and then use the Lumagen internal test patterns after that ?

Sorry, let me be more clear. Use the contrast and brightness patterns from AVIA (DVE is better) to set these. Then shift over to the internal test patterns. Do not use AVIA for setting your grayscale calibration. That is what the Lumagen patterns are for.

Quote:
You also said to hook the Denon 3910 to the Lumagen by component video rather than DVI. Can you explain why this is better ?

The 3910 has HDMI, right? Use that, but set the Lumagen to force YCbCr, rather than straight RGB. If you are going to need to use any of the Lumagen's parametric controls for corrections, you want as much virtual bit depth as possible.


Hopefully this is now more clear!

Bill