AVS Forum banner
1 - 9 of 9 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 ·
I'm a new subscriber and relative amateur with a new home theater I recently built. We have a Panasonic AE2000u, using HDMI input from an Onkyo receiver. When viewing DVD's, regular and light scenes are fine, but dark scenes are too dark.


We checked with Panasonic, who said to check Picture Mode (same if either Normal or Dynamic), Dynamic Iris (On) and Lamp power setting (Normal). When that didn't help, we sent the projector in for warranty repair....the ballast and lamp were replaced, but there was no improvement.


We have a Stewart Luxus Screenwall screen, if that is important.


Thanks in advance for any advice!
 

·
Guest
Joined
·
867 Posts
Well I do not own a Pansonic projector or a Onkyo receiver, but am bored so I will throw my 2cens worth in. Hopefully someone with more knowledge of your particular setup will give their advice.


Assuming brightness and contrast have be setup ok, using THX optomizer, DVE calibration disc or what ever. I think you are suppose to have the dynamic iris off when you setup the brightness, contrast, as the iris system also adjusts gamma on the fly. Once brightness and contrast are setup you then turn the dynamic iris on for actuall viewing.


I would first suspect the dvd player.

What dvd player are you using?

The dvd player or AV reciever may be using PC digital levels black = digital 1 & white = 255 rather than Video digital levels black = digital 16 & reference white = 235 with peak white = 255, check everything is Video levels, not PC or as some call it expanded. If something is a pc levels and something else at video levels it will screw up the image.

The dvd player analogue setup should only be an issue with analogue outputs but you never know, it maybe at 0, while the receiver or projector setup is at 7.5. In analogue it would clip black at 7.5 and make darkscenes too dark.

The dvd player may be doing something odd with its gamma curve making the bottom of the greyscale darker to boost apparant contrast in the image. My Sony DVD/HD recorder needed its brightness at +1 and contrast at -1 to look right. Some dvd players now have multiple gamma presets and contrast expansion and god knows what.


If the dvd player is not the culprit.

You may need to lower the display gamma, this will increase average image brightness, increasing the contrast in darkscenes but lowering the contrast in bright scenes. The projector appears to have three point gamma correction according to the manual, so you could try altering the gamma at the bottom of the greyscale.
 

·
Registered
Joined
·
4,477 Posts
Have you calibrated brightness and contrast with a calibration disk or TXH certified movie? Your brightness level is probably too low, but you need a disk to calibrate it and then calibrate contrast (calibrate each a few times as one can affect the other).
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #6 ·
I didn't do any video calibrating when I set up the theater....but it sounds like I should do so now.


Any suggestions on what to use to do so? Specifically what calibration disks are recommended?
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #7 ·
We connected 2 DVD/VCR combos:


- Magnavox ZV450MW8

- Sony SLV-D261P


and got very similar results using the same DVD.


I'll try playing with the projector gamma and see if that helps.
 

·
Registered
Joined
·
4,477 Posts
The easiest one to use is the Avia guide to home theater for contrast brightness and tint or you can rent a thx optimized disk which come with calibration patterns for brightness and contrast. These 2 are the MINIMUM you need to adjust.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #9 ·
Thanks to all for the comments and suggestions. I bought an Avia calibration DVD, and after going through the calibration it appears that our dark scene problem is resolved. Thanks very much.
 
1 - 9 of 9 Posts
Top