hot spot

[stinky]

Hello everyone,

I was wondering how to get rid of a hot spot in your projection. I am using a MH 400w with a powerview 820 and a fresnel lens from office max. I get a hotspot right in the middle of the screen. Does anyone know how I can fix this?

 

[Lifter]

Do you have a condenser lens between the bulb and the fresnel? You might also consider using a fresnel from an OHP verses a page magnifier.

 

[stinky]

will the condenser lens spread the light out alot?

 

[stinky]

would adding another fresnel from office max help at all??

 

[Negative Design]

i read that using scotch tape worked...i forgot the other method

 

[bitbyter]

Page magnifiers

Keep in mind that page magnifier's are just a single cheap fresnel lens. Most OHP fresnels are actually two with the grooved sides glued together. Also a condesor lens will definately help spread out your light from the F2 point.