[cavu]

apply a bit of keystone adjustment

You do not EVER want to use keystone adjustment on a theatre projector!! Power point in a convention hall is fine but the distortion and artifacts are awful!!

You are far, far better off tilting the screen forward or back a little to accommodate and, from in front, the image is perfect!

 

[cavu]

I clearly said "a little bit" because, as pointed out above, I know that keystone adjustment is to be avoided.

There is no such thing as a "little bit" of digital keystone adjustment. The instant it is applied, the artifacts appear. I don't view it as an available option at all.

 

[cavu]

The following image is nothing more than concentric circles. But depending on your display, you will begin to see some other patterns appearing near the center.

A "moire pattern" is the unique pattern that is created when you merge two screenlike objects together.

In this case, one screenlike pattern is the concentric circle design and the other screenlike pattern is the layout of the pixels on your display. Where those two screenlike patterns begin to 'interfere' with one another, a moire pattern emerges.

In video displays, moire patterns are cause when certain video images interfere with the tiny pattern of pixels on your display.

Moire distortion is an immediate and unavoidable artifact created when 'keystone' correction is added !

You don't have to believe me but in 40+ years in broadcasting, I've learned a few things. Copy this image to your computer and display it on your projector. Apply ANY amount of keystone correction and watch what happens!!

 

[cavu]

the images I see on my screen are perfect

It's too bad that your eyesight isn't good enough to perceive the moire artifacts caused by digital keystone correction, which are unavoidable. You could have saved money and bought a cheaper projector.

Prove me wrong - post comparative photos of the image (above) displayed through your 7210 with your keystone engaged and off.