CurtPalme.com Home Theater Forum

yonexsp · Joined: 25 Apr 2006 Posts: 311

Why can't I get the spot size when I did the astig on my XG as small on the green tube as the red tube?

Is it normal? I have it as sharp as I can, but can;t quite get the green astig as good as the red. The red tube os pretty much round in the center and corners.

The green is round in the center, and slightly off in the left corner. Also the spot size in ASTIG mode is bigger for the green than the RED.

Any ideas?

Ile · Posted: Tue Apr 20, 2010 7:04 am Post subject:

Have you moved focus yokes along tubes neck to find sharpest position for those. Set electrical midpoint focus to default before that.

Mark_A_W · Posted: Tue Apr 20, 2010 11:56 am Post subject:

Some tubes are just better than others I think.

My red is the same. It's sharper than green. Same spotsize behavior when you hit the astig button.

CIR Engineering · Posted: Tue Apr 20, 2010 12:35 pm Post subject:

Make sure you don't have the contrast set too high. If you overdo contrast the green will bloom first and you will lose focus.

But tubes have tremendous variation so this is likely normal.

craigr

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I have always said this, red is sharper than green. Someone somewhere mentioned its due to the phosphor properties of each color. Red doesn't bloom or spread its energy to the surrounding phosphor as much as the green does. I can not remember who said this but I find the same results on all my marquee's.

Athanasios