Hobbies
Mum’s Crochet Work
I’ve posted these images before, but for a bit of Christmas fun I’ve added some titles. Hope that you all have a very merry Christmas and a great new year. Cheers. © text & [more…]
Doc Mike Finnley
Physics
Three Gyroscopes – Part 2
Introduction The “flat earth” people like to disseminate their woeful ideas. Therefore, let us spend some little time to think about the earth that we all live upon. In particular its spherical (well, almost) shape [more…]
Physics
Three Gyroscopes – Part 1
Introduction I woke up one morning thinking, “I’ll write a few articles for GP about the gyroscope. How hard can that be?”. Hmm… Well it turns out that that was a really stupid idea. Are [more…]
Computing
A Simple R6G Dye Laser – Part 3
If you’ve been following along (well done you!) then you might recall that we need a fast switch that works at a very high voltage for the laser’s pump lamp and, indeed, for the laser [more…]
Computing
A Simple R6G Dye Laser – Part 2
Lamp Light And Laser Light Pulsed lasers, like this, use an intense burst of white light (lasting fractions of a second) to stimulate the electrons in the laser’s gain medium. In the above photo you [more…]
Computing
A Simple R6G Dye Laser – Part 1
Introduction First of all, it’s great to see that Going-Postal is still up and running. It’s always a pleasure to write an article and have it published here. It’s also good to see a lot [more…]
19th Century
Holography, Part Four
Holograph Examples The PFG-01 holographic film that I’ve used in the examples below is ideally suited to making transmission holograms but it can also be used to make reflection holograms. Reflection Holograms One of the [more…]
19th Century
Holography, Part Three
A Simple Dual Beam Setup We’ve got our film, developer and a safety lamp. Now we need a holographic camera. Well, not exactly a camera. You can’t take a picture of rolling hills or a [more…]
19th Century
Holography, Part Two
A Holographic Camera Standard photography uses a lens system to focus an image onto a film or an electronic sensor. If you recall from part one, Dennis Gabor had a problem with his electron microscope’s [more…]