Help? I can't get a focused image past a certain distance!

[frozenbum87]

ok...I have a varifocus (265mm - 305mm FL) triplet and my top fresnel (310mm FL) is about 330mm away (because this distance is supposed to be equal to or greater than the FL of the objective lens)...now, I can get a perfectly focused and bright image when the projector is anywere between 1m and 3.5m away from the screen, but when I try to move it any further, it will not focus. I need the projector to be 4.8m from the screen...what can I do to solve my problem? I've tried moving my top fresnel closer and further from the objective lens, but I'm still getting no luck. Thanks for any help!

 

[ace3000_1]

Heya buddy, the top frensel wont do too much in what your trying to do, it will generally make the image smaller or bigger. What you want to do is ajust your focal range, you do this by moving the projection lens closer or further from the lcd.

Trev🙂