Useful gadgets and home-made kit
During the session a number of members demonstrated useful pieces of kit they had purchased or constructed (because they were either expensive or unavailable commercially)
Peter Evennett
1. A simple conversion to LED illumination
It is not always necessary or convenient to set up a microscope for full Köhler illumination – as for example at a microscopical society meeting. A very simple adaptation makes use of a “magnetic reading light” from Ebay, costing only a few pounds. This consists of a hemisphere of diffusing material illuminated by an internal LED, powered from any USB source – charger or ‘power bank’, with a magnet built in to its flat under surface. Simply positioning one of these lights beneath the condenser, on the optical axis of the microscope gives beautifully even illumination, and doesn’t offend Köhler’s principles too much.
Attaching the light to the microscope might require a little ingenuity, since most microscope stands are not made of magnetic material; the lights are, however, supplied with a couple of small self-adhesive discs of magnetic material which might be attached in a suitable place. In the case of the small Zeiss microscope which I use, there is a 5mm diameter hole, on the axis underneath the condenser, originally used to carry the mirror. Not everyone knows that our ‘copper’ coinage is in fact steel, and therefore magnetic. My simple adaptation makes use of a 2-pence coin, to which I have soldered a piece of round brass rod (an old electrical plug pin) to spigot in to this hole and take the illuminator.
Illustrations -
click here
eBay link - click here
2. Mobile phone adapter
The camera on a mobile phone can produce remarkably good photomicrographs. All that is necessary is to contrive to hold the phone steady, at an appropriate distance above the eyepiece, so that the exit pupil of the microscope coincides with the entrance pupil of the camera. I have made use of a piece of wood about 1 ½ x 3 x 6 inches. I have bored a hole a little larger than the eyepiece, and lined this hole with the smooth side of self-adhesive Velcro to make a friction fit for the eyepiece. When the eyepiece was inserted the appropriate distance into this hole, I pressed a plastic lid of a 35mm film container with a hole cut in its centre, to locate the camera lens the appropriate distance above the eyepiece. A couple of rubber bands attach the phone to the wooden block.
Illustrations -
click here
3. Focus lever
Zeiss used to produce a lever which could be attached to the coarse-focus knob of the Photomicroscope or Universal microscope. This enabled the stage to be dropped to fit other objectives, for example, and then instantly returned to the focused position. I have one of these, but it doesn’t fit my smaller Zeiss microscopes. Looking in my junk box I found a nice piece of knurled aluminium of the right diameter. It was a job of a few minutes to bore it out to fit the coarse-focus knob. Then also in the junk box I found a piece of metal with a black ball on one end and a screw-thread on the other. I drilled and tapped a suitably-positioned hole in the knurled piece, to clamp it on to the focus knob. Now I can drop the stage by lifting the lever, and return it to focus by lowering the lever so that the ball touches the microscope base.
Chris Wallage
Specimen holding stand
This specimen holding stand gadget is made from a strong neodymium countersunk 15mm Magnet and a 1/4" Ball Head Bracket Mount fitting from a Camera Tripod, available from camera shops or inexpensively on eBay. Be sure the ball head is steel and can be separated from the mount. You then just need a suitable metal base to put the Magnet and Ball Head on. The screw end and disk of the Ball Head can be then glued to a suitably sized specimen holding stage. I use a round notice board magnet that grips my mineral micro mount display boxes which have fridge magnet printer paper glued to the base.
Illustration -
click here
Roger Shore
A motorised stage
This is a modification to a Zeiss Photomic stage to allow the acquisition of multiple overlapping images for the production of a single, large area and high resolution image for use in the e-Scope (Virtual microscope). The construction is based on 2 stepper motors and control board from PC Control Ltd and timing belts and pulleys from MotionCo. Images are captured via a Canon 500D and Canon remote control software. Images are tiled using Microsoft ICE. The construction of the stage is described in a presentation - click here