Background

Born in the wonderful city of Winnipeg, Manitoba in 1946, I now live in Delta, a municipality bordering Vancouver, British Columbia, Canada's most westerly province. I received my graduate (B.Sc. - Biology) and post graduate (M.Sc. - Invertebrate Biology) from Simon Fraser University. Recently retired from the federal government, my 25 plus years of service was split between Environment Canada and Public Works Canada (Environmental Services Directorate). I worked as a biologist, primarily in the areas of environmental assessment and environmental auditing. As a result of my job, my family and I have enjoyed living in several areas of Canada. Regrettably, my work seldom involved the use of microscopes.

Microscopy was a big time hobby of mine as a teenager, but fell by the way side when I became a young adult. I returned to this fascinating pastime in my late 30's while stationed in Regina, Saskatchewan. My "adventures with the microscope" persisted as I moved about the country. As time passed my interest deepened and I read extensively on the optical and mechanical workings of the microscope, trying to master techniques needed to produce high quality photomicrographs. A milestone event was the acquisition of a Leitz Ortholux, which I mated with a Canon T90 camera and flash. My interest in "microimaging" grew rapidly from that point (I have always been an avid photographer). After several years of successfully capturing all manner of subjects on film I succumbed to the lure of digital imaging, due in large part to my discovery of the Nikon Coolpix camera (I now use the CP4500). An important part of my success was the realization that one cannot achieve good results without careful attention to illumination. Bright, cool, even illumination makes a big difference. The fortuitous purchase of a stereomicroscope with a fibre optic light source lead me to the idea of adapting this type of illumination to my new scope, a Zeiss Photomicroscope II. I could not have been happier with the results, and believe you will too. Please read this short article - and if you have any questions or comments, by all means drop me a line!

Introduction

As spring rains beat against the study window you settle down for a pleasant afternoon of microscopy. Removing the cover from the scope you put a carefully prepared slide of pond water on the stage and adjust the sound system, filling the room with your favourite music, drowning out the sound of the pounding rain. Pity your friend down the road, who has taken up astronomy, not much chance of star gazing tonight! With these thoughts in mind you flick the lamp switch - the bulb flares to life, and dies. The smile fades from your lips as you search in vain for a fresh one, sadly recalling this was the last of your hoard of 20 year old bulbs. No problem, a quick (albeit wet) trip to the local lamp shop and you should be back in business. You give them a call. Yes, they have a new replacement, but the phone falls from your hand as they quote the price - more then you paid for that lovely planapo 10x on eBay! If this sounds familiar it may be time to enter the world of fibre optics, where bulbs cost less then a movie ticket and, more important, the illumination is brighter and cooler then any conventional tungsten illumination system. Interested?- read on.

I use fibre optic lighting on both my microscopes. The Leica Macroscope illumination is pretty much standard - the light source supplies a large 8 inch ringlight. However I have “retrofitted” my Zeiss Photomicroscope (PM) II for fibre optics. The PM came with a 60 watt – 12 volt tungsten bulb located in a lamp house fitted to the base by means of a bayonet coupling. For bright field, low power darkfield and phase, the bulb output was more then adequate. However, this arrangement fell short for high mag work in darkfield or phase, especially when attempting to capture a digital, or film image. Furthermore, high intensity tungsten bulbs emit a good portion of their electromagnetic energy in the infrared spectrum. Infrared radiation translates to "heat", and is readily absorbed by certain types of optical glass and other components in the optical path, especially at planes conjugate with the surface of the bulb filament, such as objective phase rings. Such heating can soften optical cement causing glass elements to separate (“delaminate”). Infrared radiation may also raise the temperature in aquatic preparations under observation – bad news for any associated micro-organisms. Converting the PM to fibre optic lighting eliminated both concerns. This article outlines how I modified the lamp house for a fibre optic feed. My approach should be suitable for lighting configurations found on most microscopes - including free standing lamps.