Many of us already have an overhead projector (OHP) and want to get MkIII results without having to build a new projector. To some extent, that is possible. You can quite easily improve your video quality by retrofitting your OHP with a DPC triplet lens. This gives a tremendous increase in clarity and focus compared to the single and double-lens assemblies that most OHP's have. It is also possible to replace the short-lived halogen lamp in your OHP with a new, long-life, brighter metal halide kit instead. This will give you at least a 100x increase in the time between lamp changes and will also improve the quality of light and color in your video projection.

Installing a 250w Light Kit

Preparing the 250w (or 400w) Light Source

Insert the New Assembly Where the Old Lamp Unit Was

Center Yourself Above the Mirror (if present) and Center the Reflection of the New Lamp

Installing a DIY Labs Triplet Lens (#06000)

After Removing the Lens Head Assembly

Disassemble the Lens Head Assmebly

After Disassembling the Lens Head Assembly

Preparing to Install the New Triplet Lens (drill 3 mounting holes in the Lower Lens Bracket)

Lens Is Mounted and the Partial Lens Head Assembly is Installed

A Picture of the completed Lens Head Assembly After Re-Assembly

The Finished Product - A Much Sharper Image From My Old Overhead Projector

Well there you have it - nothing fancy, but it makes a big difference in quality and in heat! This 250w unit is way more heat and energy efficient than the original 410w halogen lamp, and the color is now a lot better with about the same output (but much longer life!). The new triplet lens makes an even bigger difference per dollar invested, but both a new light source and lens make for the best quality image possible out of your OHP! The money spent on this projector was about $190 including the lens and light source ($225 including the cost of the OHP, which I already had from years ago).

© 2006 DIY For Life Inc