A whole           in a drop.


What happened to microscopy as a hobby?


If you were wondering why Microscopy isn’t more popular here’s a little article I put together on why this may be the case. Download (.pdf format)



Garden Exploration


I’ve exported all the garden exploration pages as high resolution (2400 x 3500 typically) jpeg images and zipped them into one file. They print out nicely at A4 and possibly A3 at a push, they could be used to brighten up a corner of  the classroom. Download (.zip 10MB approx)





If you are interested in looking at and identifying algae, here are a couple of downloads to get you started.


A Beginner’s guide to freshwater alga, published by Her Majesty’s Stationary Office (HMSO), is a small guide with descriptions and line drawings of 110 of the algae genera most likely to be found. A scan of the book in .pdf format can be downloaded, for non-profit use, from the Natural Environment Research Council (NERC).  Download (.pdf format)


The following download consists of 6 colour plates illustrating some of the more common forms of algae. I found the files tucked away on a University website as part of a public domain literature digitisation project. The plates show algae grouped in terms of likely habitats e.g. Surface water, filter clogging, resevoir etc. The images look like the originals were watercolours and make lovely wall posters in their own right. Download  (.zip format)





As you may have gathered from the garden tour, Lichens are an interesting subject in their own right. I found the British Lichens site very useful, especially the option to show the entire collection of thumbnail images. If you do this, you can save the rather large HTML page and use it offline as an interactive identification chart.  


In Firefox and with the page open, use the ‘Save page as’ option under the file menu. You should be able to save a file called ‘pictureindexcomplete.html’ together with a folder ‘pictureindexcomplete_files’ which has all the .jpg thumbnail files in. Click on the saved pictureindexcomplete.html file and it should open as if you are online.  Just mouse over the images and the Lichen name is in the image link title, which appears at the bottom of the screen. www.britishlichens.co.uk



Image Processing using Picolay


As anyone who has done close-up/macro photography knows, the more you try and magnify an object, the narrower the depth of field (smaller range of distances over which the object is in focus). Under a microscope this effect becomes extremely apparent which is part of the reason why prepared slides tend to be very thin sections. However, there are times when it is not easy or practical to prepare thin sections, instead the microscope’s fine focus can be used to ‘scan’ through a specimen. This is OK if you are sat at the microscope but not so good if you want to record the image using a camera.


One solution to the problem is to use focus-stacking software which basically allows you to take multiple images in different focal planes and combine them into one image, using only the parts of each image that are in focus. This is actually quite complicated image processing, but a very nice gentleman called Heribert Cypionka has written some software called Picolay that makes it remarkably easy to do. The 3 images below-left are the raw images, the 4th image is the post-processed result using Picolay.











Images of Hollyhock pollen processed with Picolay.




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