[Jon S]

I just picked up a Lumagen Vision and did some preliminary testing with it and noticed a couple of issues.


First, when displaying a 10 step gray scale pattern or the THX Optimode white contrast (the one with the different white blocks), the gray scale shows 90 and 100 ire at the same brightness level, The THX screen shows all the white blocks as one level of brightness instead of different shades of white.


Secondly, the image on screen tends to be a bit too "hot" in bright scenes. White areas appear to be very "glaring". This may be related to the gray scale issue but not sure. To verify, the issue appears on my CRT projector as well as a computer monitor at different resolutions.. I saw another Lumagen earlier and it did not appear to have this problem and was unable to obtain the first Lumagen for comparison.





Jon S

 

[Ben_Tech]

I am not familiar with the product, but if there is any way to adjust contrast linearity or ramping, that might be worth a look.

 

[RoberttheBruce]

I have used the Lumagen Vision with a CRT projector, dlp projector and crt monitor. The gray scale and blooming of white you mention are not visible on any of these devices. They all needed to be adjusted since the Lumagen has a unque output, as do all video devices. Calibrate to a known standard and then see what your results are like. Just to check, I put up the THX optimode on a Princeton AF-3.0HD and looked at the top end of the IRE gray. No crushing visible there.

 

[Jon S]

i have tried adjusting contrast and brightness on both the lumagen and the monitor with no luck. I have tried using it with a computer monitor and my NEC XG85 CRT, same problem. Tried also with two different players, a Sony and a Panasonic, same issue. switched out the Lumagen and plugged in a iScan and the iScan was okay (albeit at a lower res).

 

[patrick harkin]

Hi, talking to your dealer, it sounds like the color temp calibration was done incorrectly. To test this just press "menu",0,9,9,9 to reset to factory defaults. You may need to reselect your output type (ie. yprpb) after that too. You should then see the different levels.


-Patrick Harkin

 

[Jon S]

thank you, will try it tonite. such quick support is always appreciated. can't say the same for a lot of vendors now.

 

[Jon S]

set the lumagen to factory defaults and results are somewhat fixed. The Sony DVD player works fine, but the Panasonic DMR-E20 DVD recorder still has same issue. Actually, i noticed that the Panasonic grey scale is a lot worse than the Sony. The Sony would only crush the 90-100 ire windows and the Panasonic would crush 80-100 ire. Apparently, the Panasonic output voltage may be too "hot" for the Lumagen. To me, its good now since i never really use the Panasonic now.