I recently took the lid off my Z1 to blow the dust off the LCD panels. Having reinstalled the PJ, I now have vertical banding that I'm sure I didn't notice before.

I have two questions:

What causes the vertical banding on LCD projectors? A proper technical explanation would be appreciated (I am an engineer).

I've seen people refer to an adjustment that can be made in the service menu to alleviate vertical banding. Does anybody have details?

Any tips will be gratefully received.

There are several very technical threads about this in the forum. Do some searching around and you'll find plenty. I am not an engineer so I can't be of much assistance, but do some searches for voltage and banding - you should get some results. I believe it has something to do with voltage differentials across the panels.

I won't get too technical about the reason for VB. Basically the LCD panels are driven alternately to prevent the pixels from developing a "memory". The panel is divided into columns and the polarity of each column is the opposite of the adjacent columns. VB happens when there is an asymmetry between the columns.

The adjustments for VB are as follows:

Item 4 in the factory menu is a global adjustment for VB.

Items 13,14,15 in the service menu are VB adjustments for R,G, and B, respectively.

The best way I've found to eliminate VB is to first adjust item 4 as best you can, and then adjust item 14 to eliminate any remaining VB. Usually items 13 and 15 don't need to be touched.

These same adjustments will help minimize the "peek-a-boo scan line" effect.

I hope I've remembered these properly. It's been a little while!

Mike

Thanks for the responses. I had a go at adjusting the factory and service menu settings. Pretty much all the adjustments tot eh factory menu setting made things worse or at least no better. However, adjusting the the separate RGB settings in teh service menu seemed to do the trick. One in particular needed adjustment but I can't recall from memory which one.

Still I'm now much happier ... although having discovered this forum I'm now considering a crack at DIY calibration...

Dean