Datacolor User to User Support Group.

On Jul 5, 2009, at 11:38 PM, snapshotninja wrote:

> I am trying to calibrate a HP LP2475W & Samsung 226CW with a Spyder  
> 3 Pro and I have been having lots of problems.
>
> The Samsung 226CW I can't get anywhere near the HP, the colors are  
> off completely, dark green looks like grey.
>
> The HP, I can get what I think is good color, but when I try to get  
> the luminance down to around 90-120 whites look grey and look like I  
> am looking through a grey net cloth.
>
> I had the brightness down to 10 when doing it without RGB sliders to  
> get about 10 luminance, but when I used rgb sliders i was at  
> brightness 35 or so.  Either way, whites do not look white and  
> everything appears drab.

Whites on screen cannot, by definition, look gray. Dim them, and they  
make white less bright, but still white. The only ways for them to  
appear "gray" is if the user has other elements on screen that are  
brighter than application white, or ambient conditions that are too  
bright, meaning other things in the field of view that are brighter  
than screen white, or occasionally someone will use this phrase to  
mean having the contrast between whites and near whites incorrect, so  
that, while true whites look white, other light tones look too dark.  
What you describe sounds more like a gamma issue than a whitepoint  
issue. Are you getting appropriate distinction between the various  
levels of gray in the SpyderProof gray ramps in the SpyderProof image  
on the lower right? Are you in a low enough lighting condition to use  
a 90 to 120 candela whitepoint? Are there unshaded windows in your  
field of view, or insufficiently shaded? At 90 candela, the room needs  
to be nearly black, at 120, merely dim. Check your ambient light  
level, and let us know which of the five levels it is defined as.

C. David Tobie
Global Product Technology Manager
Digital Imaging & Home Theater
CDTobie@...