Home Counties Meeting at Cobham
Saturday 25th February 2023
This was the third of a series of full-day meetings in the Home Counties that we hope will encourage more members to attend face-to-face events because they will not have to travel into central London. We were pleased to see some new faces as well as the regulars. It was held in the main hall of Church Gate House Centre, where the South Thames Discussion Group met for several years, adjacent to St Andrews Church in Cobham, Surrey. The hall has a kitchen where tea, coffee and biscuits were available when we arrived and during the afternoon.
Church Gate House Centre
Talks
After a frustrating few minutes trying to find out why the mains sockets were not working, Phil Greaves gave a talk on checking microscope optics for defects and how to clean them.
Phil Greaves’ talk
Phil used a macro lens on his Canon EOS 7D to look through a series of objectives and show the effect that various defects have on the quality of the image, with the images displayed on a screen via EOS Utility on his laptop computer. By focusing at different depths within a lens, he showed scratches, dust, delamination and complete breakdown. Scratches and dust don’t always have much effect, and a Davis shutter can exclude light from the periphery and reduce the effect of delamination. Phil also showed us how he cleans lenses and explained the materials that he uses.
Phil Greaves
Click the arrow to start the video. Click the symbol to the left of “vimeo” for a larger version.
The second talk was given by Graham Matthews on Micro-miscellanea: Things to make and do. He explained how to make a Tullgren funnel from a 2-litre drink bottle,and how to make miniature needles and Irwin loops mounted in cocktail sticks. He also showed us the Angel Eyes LED ringlight that he uses on his Wild M8 stereomicroscope, and the square and round jewellery spacers that he uses to make deep well slides; he gets them from TotallyBeads. Instead of solvent-based nail varnish for making leaf peels, he now uses a resin that sets hard under UV in 90 seconds and preserves more detail, and he explained his procedure..
Graham Matthews
You can see Graham’s PowerPoint presentation here:
Click the arrows to move through the slides. Click the symbol at bottom right for a larger version.
Gossip
After the talks, we had a break for lunch, when most of us enjoyed fish and chips from a shop in Cobham, kindly collected by Joan Bingley. Then we spent the rest of the afternoon examining and discussing the exhibits that members had brought.
Lisa and Nigel Ashby showed a black and brass Watson Low Power Binocular microscope with two pairs of objectives, a pair of unusual ×6 Complec eyepieces for spectacle wearers, a box of tools that used to belong to a man who repaired Watson lenses, two other boxes of tools, and an assortment of materials that they use for restoring microscopes, wood, leather, etcetera.
Lisa and Nigel Ashby’s exhibit
The materials included NAF Leather Saddle Soap, Abbey 1982 Saddle Balm, diluted Johnson’s Baby Shampoo, and three products from Picreator, Renaissance Metal De-Corroder, Pre-Lim metal burnisher and Renaissance Micro-Crystalline Wax Polish.
Tools for repairing Watson objectives
Watson Low Power Binocular microscope
Mark Berry brought a small Orion stereomicroscope on the back of which he had mounted part of a C. Baker binocular compound microscope with a coarse-focus mount.
Orion stereomicroscope and Baker compound microscope
Mark also brought a Vickers binocular microscope with a substage condenser modified to accept a 25 mm wide slider. He uses a normal microscope slide as a slider, and brought the turntable that he had modified so that he can scribe a clear circle on a slide that he has painted matt black. It uses a cut-down gramophone stylus to scrape off the paint and produce a phase contrast annulus.
Turntable for scribing phase annuli in matt black paint
Joan Bingley used a small Brunel stereomicroscope to show grains of basalt from Macquarie Island mounted in an unusual slide made by Ernie Ives that has a removable coverslip. Collecting is not allowed on the island, but Joan recovered grains that had been deposited on her clothes and equipment by the wind and the rain.
Joan Bingley’s exhibit
Basalt grains from Macquarie Island
Steve Durr used his Zeiss Standard microscope to show slides of Cryptococcus neoformans (a filamentous fungus) in human lung.
Steve Durr’s exhibit
Pam Hamer used her Vickers compound and stereo microscopes to show us samples and slides of mudstone that she collected in March 2022 from Compton Bay in the Isle of Wight. She spotted a stone with distinctive layer structure indicating a sedimentary rock origin, but she could see some shiny crystals so she took it home to examine it.
Pam Hamer’s exhibit (with Paul Smith and Anthony)
The mudstone started to break down after Pam took it home, and she observed and recorded the changes using reflected light, transmitted light and crossed polarisers.
Degraded mudstone with plant material, pyrite and ferrous sulfate
You can see Pam’s PowerPoint presentations about her mudstone here:
Click the arrows to move through the slides. Click the symbol at bottom right for a larger version.
Click the arrows to move through the slides. Click the symbol at bottom right for a larger version.
Pam also brought lots of copies of the leaflets that we give away at meetings and outreach events. They are also available as PDFs from the Downloads page on the Club’s website.
Quekett leaflets
Graham Matthews brought the Mark II version of his home-made Tullgren funnel, which is more stable than the first version and has a removable container for the specimens. He uses it to extract arthropods from leaf litter and bird nests from Warnham Local Nature Reserve, and he brought several slides of fleas and mites that he has made.
Pam Hunter and Graham Matthews
Slides of fleas and mites from leaf litter and bird nests
Mark II home-made Tullgren funnel
Graham also brought a few of his slides of leaf peel impressions made with a resin that sets hard in UV. He uses 4th generation Vida Rosa UV Resin that comes in 100 gm bottles, and he uses a UV lamp intended for curing nail varnish. He makes his paper covers on a computer, which makes it easy to get the aperture the right size and position for each specimen.
Paper-covered slides of leaf impressions in UV-setting resin
Graham demonstrated how to make a leaf impression of the underside of a leaf of Geranium sp. and later photographed it using DIC:
Leaf peel of Geranium
In his talk, Graham explained how he bores a hole in the end of a wooden cocktail stick to make a holder for a fine needle or an Irwin loop, and he brought some sticks and loops of various sizes to give away.
Irwin loops mounted in cocktail sticks
Robert Ratford filled a table with his exhibit. He used an AverVision F15 Flexible Arm Visualizer to show images of feathers on a monitor, lit by a Claoner lamp with 4 strip lights on flexible arms. To show whole wings of birds, he used a GXMMZS0745 stereomicroscope with a simple LED ringlight. To show more feathers, he used a Brunel stereomicroscope with a simple LED ringlight.
Robert Ratford’s exhibit
Bird wing under stereomicroscope
Feathers under stereomicroscope
Kit of small tools
Bevil Templeton-Smith is a new member and has only been interested in microscopy for about three years. He uses Leitz Orthoplans and a Sony α7R IV camera and takes excellent photos of crystals under polarised light. He showed us several of them on his tablet, and you can see more of them on Instagram. From 10th to 26th March 2023, he has an exhibition of 16 large dye-sublimation ChromaLuxe prints on metal: “Polychromo” at Alveston Fine Arts in Notting Hill.
One of Bevil’s photos printed on metal for the exhibition
Acknowledgements
Our thanks to Joan Bingley for organising the event and helping with refreshments, to Margaret Greaves for helping with the refreshments, and to all those who got out and put away the tables and chairs.
Report and most photographs by Alan Wood