Please help! Dark areas on CRT mess with alignment

[thealtkey]

I have a Viewsonic P95F+b 19" aperture grille CRT, and I'm having a really strange problem. Long (horizontal) areas of dark color throw the image out of horizontal alignment. For example:

<pre> +==========================+
| |
| |
| |
| +---BLACK----+ |
| +----BOX-----+ |
| |
| |
| |
+==========================+</pre><p>I can create a new layer in Photoshop, draw a thick, black stripe, and when I drag it up and down, I can watch the image in the horizontal area of my screen distort, which makes pixel-precise work almost impossible.

The darker the color and the longer the area, the further out of alignment the parts of the image will shift. None of the built-in adjustments seem to help, but the problem does get worse as brightness is increased. At 85% brightness in the monitor's Normal mode, it is rather noticeable, and it only gets worse from there.

It's not such a problem during web surfing or gaming, but being a web designer and a photographer, it's really impeding my work. What could possibly be causing this problem, and (I probably already know the answer to this) is there any way I can fix it? Thanks in advance.

<b>UPDATE:</b> I just realized that the severity of the distortion is also affected by the proximity of the dark area to the edge of the screen. The further away the object is, the less severely it will affect the rest of the screen.

Also, the distortion is as diagrammed above, with the parts of the image shifted to the left. Also, I should mention that the problem is not related to the stabilizing wires, both of which are in perfect alignment (until you drag a dark area across one of them, of course).

Thanks again, everyone.<P ID="edit"><FONT SIZE=-1><EM>Edited by thealtkey on 08/17/05 03:18 AM.</EM></FONT></P>

 

[folken]

Are there any big magnets or magnetic field creating devices near it? Have you degaused it? Have you tried lowering your refresh rate, resolution, or viewing area?

Otherwise it is new monitor time...

<A HREF="http://www.folken.net/myrig.htm" target="_new">My precious...</A>

 

[thealtkey]

I've degaussed, and the closest magnet is a 19" TV sitting approximately 18" away. It's actually closer to my friend's monitor (our PCs are set up at the same desk), and he isn't having the problem. It was doing this before I moved it to this location anyway. Here's what I gathered from testing:

- Changing resolution had no effect.
- Adjusting the dimensions and zoom of the viewing area had no effect.
- Setting the refresh rate to 70Hz or 85Hz made the problem go away. All other settings were problematic.
- At refresh rates which displayed the problem, a faint shadow was visible on either side of the dark area.
- The problem does not seem to change in relation to distance from the edge of the viewing area.

Overall, it just seems as though when a long, dark-colored strip is being displayed, the image in its horizontal area bends about a pixel or so to the left. So this leads me to the question: what is the hardware doing when it has to display dark color? It seems obvious the problem is there.

I know a fair bit about CRTs, but I'm no expert. Any ideas?

<b>UPDATE:</b> I also just noticed that when I place a light area (ex. the toolbar in Photoshop) over a dark area (ex. a layer filled with dark purple), the light bleeds over into the dark area. I know that a CRT's ability to display black is really its ability to block light, so this is understandable.

Could this also be applied conversely? Could "light" from a dark area bleed over into a light area, causing image distortion? Is it possible that this isn't even a defect at all, and I am simply the owner of a most craptacular display? Image and color accuracy is key to what I do, so it would be nice to figure out how to resolve this.

Thanks again.<P ID="edit"><FONT SIZE=-1><EM>Edited by thealtkey on 08/19/05 05:01 AM.</EM></FONT></P>

 

[RichPLS]

What happens when you wop it on the side of the case?

<pre><font color=red>°¤o,¸¸¸,o¤°`°¤o \\// o¤°`°¤o,¸¸¸,o¤°
And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign</pre><p></font color=red>

 

[folken]

Looks like it is time to move to an LCD. Those are good for image color and accuracy
Every webdev and photographer I know has switched to an lcd.

<A HREF="http://www.folken.net/myrig.htm" target="_new">My precious...</A>