Air bubbles in packing tape

[Charles Krebs]

Sometimes when I have a subject (in this case it was a small testate amoeba) where the cover might crush it I will make a "channel" with two strips of tape on the slide. The subject goes in the channel and the cover-slip then bridges these strips which prevent it from dropping too far and smashing the subject (hopefully! )

After finishing up with the amoeba, I wandered over to the tape and found these interesting patterns that were formed by air bubbles trapped in the adhesive. (This was clear package sealing tape). It was interesting in that the tape radically changed the DIC colors... acting just like a retardation plate. If you don't have any retardation plates a strip of tape on the bottom of the slide when shooting crystals with polarized or DIC might prove interesting.

[Rylee Isitt]

Charles,

These are very cool shots. Thanks for posting!

[Cactusdave]

Different thicknesses of Sellotape mounted on a glass slide can make an effective retarder for use with polarised light. In fact I used a very effective retarder made from two layers of Sellotape to take the first image in this post http://www.photomacrography.net/forum/v ... hp?t=18611 . I was introduced to the technique at a recent meeting of the Quekett Microscopical Club to which I belong on the subject of polarised light microscopy. Two layers of Sellotape give a retardation approximately equivalent to a first order red plate, what used to be called a 'sensitive tint' plate, with a magenta background. There is more on the effects of plastic films and Sellotape as retarders in polarisation here. http://www.nhm.ac.uk/hosted_sites/queke ... rised.html

[g4lab]

http://www.amazon.com/Crystals-Light-El ... 0486234312

[aurabackdrops]

Excellent..! What a very impressive shots..