{"id":58,"date":"2008-09-23T13:34:21","date_gmt":"2008-09-23T22:34:21","guid":{"rendered":"http:\/\/stereo.thurstons.us\/content\/?page_id=58"},"modified":"2009-02-24T17:40:15","modified_gmt":"2009-02-25T02:40:15","slug":"3d-world-viewer-illumination","status":"publish","type":"page","link":"https:\/\/stereo.thurstons.us\/content\/?page_id=58","title":{"rendered":"3D World Viewer Illumination"},"content":{"rendered":"

<\/a>How It’s Lit<\/h3>\n

The illuminator in the 3D World viewer<\/a> is an edge-lit panel. It works by shining a light into the polished bottom-edge of a lexan sheet. Through internal reflections, the light is directed out one of the flat surfaces of the sheet. It provides a very even light in a very thin package. I’ve always considered edge lighting to be the most desirable way to light a slide viewer. I’m very pleased to see 3D World using the concept in their newest viewer.<\/p>\n

\"\"<\/a><\/p>\n

Several years ago, I modified one of the 3D World steal-the-light<\/a> (STL) viewers and inserted an edge-lit panel. I used a panel with a fluorescent light source, and powered it from the wall rather than from batteries. The result was an extremely thin, very bright light that hid in the back of a my fixed-focus viewer.<\/p>\n

In the intervening years, I have considered installing a battery pack in my illuminated viewer, but the power demands of the fluorescent light made that impractical. I have also tried several times to build an edge-lit panel using LEDs in place of the fluorescent tube. The result would have been an instant-on light with a smaller electronics package and lower power consumption.\"\"<\/a>I was never able to design an LED-lit panel which provided light sufficiently even for slide viewing.<\/p>\n

Thank goodness 3D World has succeeded where I was stymied. They have designed and built an LED-lit panel suitable for use in a slide viewer. Because it is instant-on (unlike fluorescent), it can have a momentary switch. Because it has a momentary switch and LEDs with low power consumption, it can be battery powered. Because it’s edge-lit, it is very thin and because it’s very thin, the final viewer can be very compact.<\/p>\n

<\/a>How Does It Perform<\/h3>\n

I now have three illuminated medium format viewers:<\/p>\n\n\n\n\n\n\n
Viewer<\/strong><\/td>\nLight Source<\/strong><\/td>\nPower Sources<\/strong><\/td>\n<\/tr>\n
Saturn Viewer<\/td>\nhomemade fluorescent
\nedge-lit panel<\/td>\n		6 AA batteries
\nexternal power<\/td>\n<\/tr>\n
3D World STL Viewer<\/td>\nhomemade fluorescent
\nedge-lit panel<\/td>\n		external power<\/td>\n<\/tr>\n
3D World Illuminated viewer<\/td>\nLED edge-lit panel<\/td>\n3 AA batteries<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

An ideal viewer light will be light weight, sturdy, inexpensive, evenly lit, bright, long lasting, and of a daylight color temperature. All of these attributes can be hard to find in a single product, but I’ve made some measurements of my lights for comparison.<\/p>\n\n\n\n\n\n\n\n
Viewer<\/strong><\/td>\nVoltage<\/strong><\/td>\nCurrent<\/strong><\/td>\nWatts<\/strong><\/td>\nISO 100 EV<\/strong><\/td>\n<\/tr>\n
Saturn Viewer<\/td>\n9.51 external<\/td>\n.3<\/td>\n2.85<\/td>\n11.5<\/td>\n<\/tr>\n
3D World STL<\/td>\n9.5 external<\/td>\n.3<\/td>\n2.85<\/td>\n12.6<\/td>\n<\/tr>\n
3D World Illuminated viewer<\/td>\n4.67<\/td>\n.20<\/td>\n0.93<\/td>\n12.0<\/td>\n<\/tr>\n
3D World Illuminated viewer<\/td>\n3.85<\/td>\n.16<\/td>\n0.62<\/td>\n11.6<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A few notes regarding these measurements:<\/p>\n