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Thoughts about transformational technologies; musings about momentous methodologies; awareness of awesome apps….

Going Green


Green screens have been around for some time now.  In very simple terms, green screens provide a transparent background behind an object (such as a person); the final background image is then superimposed creating the illusion of the person actually being there. A classic example is weather reporting on TV.

The reason that bright green is used is that there are no green pigments in skin, so skin will always remain opaque when you film. However, if a person wore some green clothing, it would become transparent and let the background shine through- with interesting effects! 

As technology advances, it is becoming incredibly easy to harness the potential of green screen techniques in the classroom.

Equipment Needed

All that is needed for green screening is a green background- you can buy green cloths; you can paint a wall matte green; you can buy pop up frames; or in schools, you can use green backing paper! A mid green colour works best.

The more even the green background, the better the final result will be. If you use cloth, hang it a couple of hours before use to let the creases drop out and use some weights or clips to stretch the cloth. You could also mist the cloth lightly with a spray to help the creases fall out, although test on an inconspicuous part as water will darken the fabric.

Good lighting will dramatically enhance the final result too.  Photo studio lights with daylight bulbs will improve filming if it is in a dark room with yellow lights in the ceiling. If a classroom is naturally bright you should be fine.


For iPad there are great green screen apps- my two favourites are:

Green Screen by DoInk


Both are extremely easy to use, although they work in slightly different ways.

With Veescope you choose your background first; then film in front of the green screen.  Both the background and the subject are merged together at the same time. It is good for on the fly work.

With Green Screen by DoInk, you can separate the clips; you can film against a green screen first, then bring the green video clip into the app and add the background (or backgrounds).  The significant advantage is that the background can be changed if it is not right, without having to film all over again. Another great advantage to DoInk's app is that you can adjust the green using the colour dial to remove all traces of green.

The possibilities of green screen are endless and there are so many applications across the curriculum. Fantasy, pupils describing settings; non-chronological work; news reports; any work that is prefaced by you asking the pupils to "Imagine...."; pupils explaining properties of shapes in maths... and for real impact pupils need to learn how to pretend and act!

Happy green screening!

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Blue- this is how Beautiful Sounds

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Blue- this is how Beautiful Sounds


USB microphones can be cheap and cheerful. In recent years with more and more emphasis on pupils using technology in and out of school, the need for higher quality microphones has become more pressing. 

For years I have used Samson USB condenser microphones, such as the CO1U and the CO3U. They are robust, heavier and when pupils have used them they feel as if it is "the real thing". However, I wanted a more versatile microphone for recordings; one that would record using different patterns for different purposes- whether it is a solo voice, an interview either side of the microphone, birdsong in the garden, or a school choir.

There are four main recording patterns:

Stereo- for recording sound in front of you from left to right

Omnidirectional- for recording sound from all directions

Cardioid for recording sound from one direction

Bidirectional- for recording either side of the microphone, but ignoring sound from the side. 

Each pattern has its own advantages and is suited to different purposes. For example, an interview between two people would be best in the Bidirectional position. Recording an orchestra could be recorded in Stereo. A solo voice lends itself to Cardioid.

Time for Change

This morning I took delivery of a parcel. Inside it was my newly purchased Yeti Platinum Edition. My first thought was "This IS heavy!"

Everything about it from the way it is carefully packaged to the way it catches the light hints at something of real quality. It looks beautiful. It feels beautiful. It sounds beautiful. 

The sound quality is so good it even picked up the background noise coming from the (non-SSD) hard drive on my iMac into which it was plugged and the vibrations it was sending through the desk- and the Blue Mic has a layer of sponge on its base! I resolved this by simply picking up the microphone and speaking and the background vibration immediately disappeared. Rather than place the microphone on the table, I will either: position the microphone away from the recording computer, or I will be investing in the shortly-to-be-released Radius II Shockmount. It has been improved since the original Radius with a hinged design and better clamping to position the microphone. 


It goes without saying that I am absolutely delighted with the clarity and quality of the new Blue Yeti. It will be perfect for many of the occasions where I need good quality results quickly with minimal setup. It will certainly be useful for whole class recordings; but it is not going to resolve the perennial issue of lots of pupils recording on lots of devices at the same time in a classroom. For rough recordings pupils will be quite satisfied with this; but as with all things, if you want real quality, you need to find somewhere quiet to make final recordings. I will be there with my Yeti to ensure the final result is admirable not abominable!


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