I decided to take a closer look at the Orange Hawkweed I'd found on the back lawn (see previous post). I was intrigued by the way the anthers were wound up tight and would unravel in bright sunlight.
The above picture was taken through a trinocular microscope at a magnification of 100x. Trinocular meaning that in addition to the two widefield eyepieces giving a binocular view of the specimen it has another vertical tube to which I can attach my camera. It works well with the Canon 550d DLSR which is hooked up to the Canon Liveview software via USB connection on my laptop. I like this arrangement because I can see the view through the microscope clearly on the screen and control various camera functions eg exposure or ISO settings and I can accurately focus.
I didn't use the microscope light source but used an LED photo light to illuminate the subject from above. Normally the specimen would be lit from a light source at the base of the scope and shine through it to give a flat 2D view. This is fine for transparent, thin objects but non transparent subjects will appear as dark featureless blobs.
Even using the photo light all I see is one tiny focused section of the subject and the rest is a blur. So I took 65 separate images each one at a slightly different focus until I could see that the whole 3D object had been covered.. I then use a brilliant piece of freeware called CombineZP which 'stacks' all 65 images, aligns them and then combines them by selecting only the sharpest focused parts of each image to produce the result above.
Yellow ball shaped pollen can be seen attached to the anthers. Shortly after this picture was taken the whole structure started to unwind. It could be a good subject for a time lapse movie.
Orange Hawkweed Pollen 200x. Each pollen grain has a spiky surface which helps it stick to any visiting insect.
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