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  1. Last week
  2. So, it’s been a few years since I’ve detailed how I make my screencasts, and my workflow and equipment have evolved as I’ve added a few bells and whistles in an attempt to make the screencasts look a touch more professional (and more fun). Some things have stayed the same, and others, well, not so much. Here’s the basic workflow. The Computer 27″ iMacI’m still working on a Mac platform, doing most of my work on a 27-inch 2013-vintage iMac. I try to keep up to date with the latest version of the operating system, which is currently OS X Sierra. The iMac includes the higher-end graphics card (NVIDIA GeForce GTX 780M 4096 MB), has an i7 processor, and I’ve installed 32 GB of RAM. Typically when I purchase a computer I shoot for a five to six year productive life span, at which point I’ll upgrade to a newer model. This has worked pretty well for me with respect to my Mac laptops (a MacBook Pro), as the last one was in service for about six years, but I’m anticipating this iMac may continue well past that mark. It still looks beautiful, runs quickly, and with the amount of RAM and the built-in Fusion Drive, its performance doesn’t appear to be in any danger of slowing down in the near future. Pen Displays Wacom Cintiq 22HDAttached to the iMac I have a Wacom Cintiq 22HD pen display unit, which is basically an external monitor that I can “write on” with a special pen, allowing me to annotate the screen as I talk through the video. I’ve previously used a Wacom DTU-1631, and am looking forward to trying out the newly-released Wacom Cintiq Pro 16 with a USB-C enabled MacBook Pro. Though the Wacom pen displays are a very significant investment, I’ve been very impressed with their quality and longevity. The DTU-1631 has lasted five years in the classroom with heavy daily use, and the Cintiq 22HD is just shy of five years of service (though a much lighter workload) and could easily pass for brand new. These monitors also hold their value extremely well over time. Audio & Video Blue Yeti MicrophoneI’ve gotten a ton of mileage out of my Blue Yeti USB microphone… I’ve tried a number of other mics, including lapel mics, and microphones that cost more than three or four Blue Yeti’s, but I haven’t found anything that compares to the quality of the Blue Yeti, especially at its very reasonable price point. If you want to upgrade your audio from the built-in microphones, this is a very solid choice, and another piece of electronics that has held up well for more than five years of service. Canon Vixia HF G20I’ve put together a small office in my basement to allow for a fairly quick and seamless transition to video creation mode, which includes a foam green screen (and stand). Especially if you’re just getting started, something as simple as a green flannel blanket can work, though I have to admit, the foam green screen has held up extremely well these past few years (even with the dog sleeping on the portion that sits on the floor at least daily). They sell rather expensive lighting clips to hold the green screen to the stand, but I found quality clips at a much more reasonable price at the local hardware store. Genaray SpectroLEDFor illumination, I use a couple of super-cheap reflector work lights coupled with a Utilitech Pro floor LED and a Genaray SpectroLED SP-E-240D mounted on the ceiling. With a little bit of playing, I can obtain pretty reasonable uniform green screen illumination. I also use a couple of desktop clip-on lamps to illuminate the foreground (i.e. — my face) in the videos. To record my face in the videos, I’m using a Canon Vixia HF G20, saving the digital video file onto an SD card. Most any digital camcorder or webcam can do the job, however. While the Canon is recording my face, I’m separately using the iMac and Telestream’s Screenflow 6 (Telestream JUST released Screenflow 7, but I haven’t tried it out yet) to record the Wacom Cintiq screen, as well as recording the input from the Blue Yeti microphone. Recording Prior to any recording, however, I create my “slides” for the screencasts using Apple’s Keynote software, and export those slides as a PDF. I then open the PDF using Zengobi’s Curio software, which is the software actively running on the Wacom screen that I use to annotate the slides. If you haven’t tried it out, Curio is a pretty amazing piece of software that allows you to do so much more than just write on PDF slides… if you have a Mac, it’s worth checking out for a variety of purposes! So, the workflow. With everything set up, I have Screenflow 6 start recording the Wacom screen while recording the Blue Yeti mic, and simultaneously I start up the Canon video camera. Once I’ve gone through the lesson, I stop Screenflow from recording and stop the Canon video camera. I should now have an SD card that contains the digital video file of my face (with sound recorded from the Canon’s rather poor microphone), and a Screenflow 6 file that has video from the Wacom screen coupled with the Blue Yeti-recorded sound. Now it’s time to put the video all together. First I export the digital video file from Screenflow 6, taking care to export at 29.97 fps and not 30 fps so that it will match up to the Canon digital video file. Then, using Final Cut Pro on the Mac (coupled with the Motion and Compressor add-ons), I create a project and import both the recorded screen video file and the video camera file. Using Final Cut, I create a combined clip from these two files and have Final Cut Pro sync them up based on the audio (although the sound from the Canon camera is poor, it’s good enough to sync the clips together). Next, I mute the sound from the Canon camera, so that I now have my recorded screen video below my “live action” video, but using only the sound from the recorded video screen, which was recorded with the Blue Yeti mic. Editing Chroma Key EffectNext it’s time to edit. First step is to take care of the green screen effect (formally known as chroma key), which Final Cut Pro does quite easily. I remove the green color from the “live action” file using the “Keyer” effect, and tweak it as needed to get the desired result. I then shrink the clip down and position it where I want, so that I have the live video taking up just a small portion of the screen, the background green from the video shows as transparent, and what shows through from underneath is the recorded video from the Wacom screen. The hard part’s done. Final steps now involve fixing any audio issues, clip editing if necessary, adding any titles, and appending on the opening and closing video sequences, which were created using Adobe Premiere Pro, After Effects, and Audition from Adobe Creative Cloud. Once I have the video looking the way I want in Final Cut Pro, I use Compressor to export it in multiple formats — high definition video for YouTube, and an APlusPhysics-specific size and quality for viewing directly from the APlusPhysics site. Next Steps Moving forward, I would really like to spend some time working with my old iPad to see if I can re-purpose it for use as a teleprompter. I tend to spend a lot of time up front planning my videos, but still have yet to come up with a slick, efficient way of presenting notes to myself while I’m making a video. I have to believe there’s a reasonable way to have my notes show up on my iPad and use some sort of remote (perhaps my phone?) to scroll through PDF notes on my iPad as necessary. Currently I tend to tape my paper notes to the bottom of the camera, which is chock-full of problems, messiness, and opportunity for improvement. Back to Reality If it sounds like there’s quite a bit of work involved, you’re not wrong, but don’t think you have to go to anywhere near this level of complexity or expense to make quality screencasts. My workflow has evolved over the years as I’ve tinkered and gone through a length set of try/fail sequences to learn what works for me and provides the level of quality I’m after. Much of what I do can be accomplished in a similar manner using fairly basic tools — Techsmith’s Camtasia software coupled with a Webcam, a USB lapel mic, and most any digitizing tablet will get you pretty solid results without a huge investment. Even though this article is a technical how-to / what do I use, I’d still like to end with two bits of advice I’ve learned from doing things the hard way more times than I can count. First, and foremost, a flipped classroom is NOT about the videos, it is about building more in-class time for active learning strategies such as hands-on activities, group problem solving, deep-dives into a topic, discussions, etc. The videos themselves are such a tiny part of the whole equation, and are primarily a means to create more available class time. Second, though it can be fun to doctor-up your videos and add all sorts of bells and whistles, realize that these embellishments and investments of time and resources have extremely minimal payback in the form of student learning and performance. If you’re interested in doing these things, make sure you’re doing them because you want to and think it’s going to be fun, but don’t expect to see any sort of substantial learning improvement with higher quality videos (which brings me back to item one… it’s not about the videos!) Useful References Video: Developing a Successful Flipped Classroom Video Series: How to Get the Most Out of Studying (Dr. Chew) The post Creating Screencasts (Mac) – 2017 Update #edtech #flipclass appeared first on Physics In Flux.
  3. Earlier
  4. Jason Padgett sees the world in Math equations!

    Keep up the good work!
  5. Final Video Project

    Hey Mr. Fullerton and anyone whos reading this, its been a pleasure grinding this year. Hope you enjoy this great video and maybe even chuckle a bit.
  6. Physics behind tennis

  7. Launch Time: 10:37 am Team Members Present: Jason Stack, Marcus Nicholas and Michael Kennedy were all present for this launch. Play-by-Play: Initially the rocket was created using the parts listed in the pre-flight briefing. The rocket was launched from Kerbin and angled in order to successfully travel outside of Kerbin's atmosphere. The rocket was then directed into orbit around Kerbin. Kerbin was orbited a few times. The rocket was then returned back to Kerbin by using a maneuver that brought the rocket back into Kerbin's atmosphere. The bottom engines were released, then the second engines, leaving only the pod left. The pod descended to 1,000 meters above Kerbin and then the parachute was deployed. The pod landed safely on Kerbin. Photographs: Time-of-Flight: 4 hours and 5 minutes Summary: Our flight was a great success. We planned to accomplish all initial milestones, including a successful manned orbit and a successful Kerbal EVA. All of these desired milestones were accomplished. Our spaceship and Kerbal manning the ship returned safely to Kerbin after successfully reaching orbit around Kerbin. By reaching a manned orbit around Kerbin, all the initial milestones were accomplished by this launch. Opportunities / Learnings: Establishing what the launch goals are and designing the rocket accordingly is very important. Failure to do so will result in an inability to accomplish any milestones. Strategies / Project Timeline: After this accomplishment, our next goal is to reach orbit around the moon and land on the moon. Milestone Awards Presented: Launch to 10 km - $10,000 Manned launch to 10 km - $20,000 Manned launch to 50 km - $30,000 Achieving stable orbit - $40,000 Achieving stable manned orbit - $50,000 First Kerbal EVA - $60,000 Available Funds: $257,818
  8. Nicholas Enterprises Starting Funds: $60,000 Vehicle Name: Mr. Rocket Vehicle Parts and Cost: MK16 Parachute X1, LV-909 Liquid Fuel Engine X1, FL-T800 Fuel Tank X1, TT-38K Radial Decoupler X3, RT-10 Hammer Fuel Booster X3, MK1 Command Pod X1, AV-T1 Winglet X3, TR-188 Stack Decoupler X2, Aerodynamic Nose Cone X3, FL-T400 X1, LV- T45 Engine X1. Total Cost- $12,182 Ending Funds- $47,818 Design Goals: Our rocket has been designed to successfully go into orbit around Kerbin and then return safely back to Kerbin. Launch Goal: Our goal for our launch is to go into orbit around Kerbin. Pilot Plan: The pilot should exit Kerbin’s atmosphere and then turn at the proper angle to cause the ship to go into orbit around Kerbin. Illustration:
  9. Week 3

    Glad to hear it went well. The center of mass concept is one that many times allows you to solve problems more simply than traditional 'plug and chug' formulas. You'll find it useful in a variety of units in the course!
  10. Licking a Battery

    mad skimpy yo
  11. Metal Cereal?

    Not many people put a whole lot of thought into what their morning cereal is made of. Most people would just assume there's some grain and maybe a little sugar, or a lot of sugar if you're more of a Lucky Charms person than a Raisin Bran person. Nobody would suspect, though, that there would be metal in their Cheerios. Turns out, Cheerios are magnetic. Or are they? Fill a bowl with water and drop in a couple Cheerios. Take a magnet and hold it just above the Cheerios, the Cheerio will be attracted toward the direction of the magnet. Why is this? If the little cereal ring is magnetic, then there must be metal fragments in it causing the attraction. Now the cereal is all magnetic, and it does contain tiny fragment of iron. This is perfectly reasonable though, as iron is a key nutrient in a human diet. But that's not the whole story, If you were to try this with objects other than cereal, say a small piece of paper or plastic, it would still seem to be attracted to the magnet as it floated in the water. The "attraction" you see is actually all about water, which is diamagnetic, meaning it generates a magnetic field opposite to that of the magnetic field it is in the presence of. Thus, the water is slightly repelled by the magnet. This causes a slight divot in the water, that the object in the bowl actually falls into, making it appear to follow the magnet. In actuality, it isn't being affected directly by the magnetic field, but by the waters reaction to the magnetic field.
  12. The Physics of KSP

    Sounds like you'll have a head start on our "post-AP" project!
  13. An Physic C

    Not quite sure I understand what "Mr. Fullerton is for the boys" means, but glad to hear you've gotten something out of the course. I, too, am glad you've stuck with it. Couple more weeks of pushing and the finish line is in sight!
  14. Twilight Physics

    I was right with you up to the part where you said "it isn't that horrible of a movie." The missus made me sit through it once. The post-viewing fever lasted three days. I was right with you up to the part where you said "it isn't that horrible of a movie." The missus made me sit through it once. The post-viewing fever lasted three days.
  15. Doctor Who Makes No Sense

    And of course there's that whole "Gallifrey and the Daleks are time-locked" complication. As corny and goofy as the show is, what always impresses me is the quality of the writing... and I'm really enjoying the fact that my 7-year-old is now all about watching Doctor Who with her dad whenever mom isn't home (Mommy would find it 'inappropriate.')
  16. Little Tiny Pieces

    You're on the home stretch of a mighty difficult course, not just in content but also in terms of level of independence. You've done well -- keep it up for just a few more weeks!
  17. The Physics of Moving On :(

    Sure been nice having you in here!
  18. Physics of baseball

    When a person swings a baseball bat and hit a ball with a wooden bat rather than a aluminum bat, it will generally not travel nearly as far. Why is this? This is a concept of momentum on the baseball field. The biggest reason for the ability for a person to hit a ball further with an aluminum bat is because when they do, they are able to swing the accelerate the bat to higher speeds than if they were to use a wooden bat. Momentum is directly proportional to velocity therefore the faster the swing of the bat the further the ball with travel in most cases.
  19. Physics of Frisbee

    A common item such as a Frisbee has very complex physics concepts that explain why it behaves a certain way. The two main physical concepts behind the Frisbee are aerodynamic lift and gyroscopic inertia. The two main aerodynamic forces acting on a Frisbee are the drag and lift forces, these forces have a relation ship with one another and is used in order to determine the magnitude of either force. The rotation of a Frisbee is a necessary component in the mechanics of how a Frisbee flies. Without rotation, a Frisbee would just flutte rto the ground like a falling leaf and fail to produce the long distance flight that it does when thrown the right way. This is caused by the fact the aerodynamic forces are directly centered on the frisbee. In general, the lift on the front half of the disc is slightly larger than the lift on the back half which causes a torque on the Frisbee. When a Frisbee isn’t spinning, this small torque flips the front of the disc up, and any chance for a stable flight is lost.
  20. Physics of Swimming

    Swimming is a popular activity, both for recreation and competition. The physics of swimming involves an interaction of forces between the water and the swimmer. It is these forces which propel a swimmer through the water. When a person swims there are more forces acting upon them than you might think. First off a swimmer must push off the water in order to create thrusting force generally parrallel to the surface of the water, There is also the force of gravity on a person working in the y-direction however much of this force in cancelled out by the force of buoyancy. Lastly there is also some kinds of drag force That acts similar to a force of friction in the direction opposite of that the swimmer is moving in.
  21. Physics of sound

    Even the most fundamental things have physics concepts behind them, In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure, through a transmission medium such as air or water. This is also where physiology comes into play as well. The sounds we are all so familiar with are only our brains interpretation of sound waves leaving from somewhere else. Humans can hear sound waves with frequencies between about 20 Hz and 20 kHz. Sound above 20 kHz is ultrasound and below 20 Hz is infrasound. Other animals have different hearing ranges. How we interpret this sound will depend on the frequency of the sound waves that travel from something to a person.
  22. Physics in Archery

    During archery in gym class, I'm usually one of the people who gets my hands on the nicer quality bows. But today I was sad to find myself with one of the weaker, green bows. I had never shot with one of these bows, so when I took my first shot the same way I normally would, I was surprised to find that it fell to the ground just before hitting the target. I realized that this was simple physics, and I could easily fix my shot. The green bows have much less tension in the string than the longer wooden bows, meaning that when released, they exert less force on the arrow. So my arrow was leaving the bow with a much slower horizontal velocity than normal. Obviously, the downward acceleration wouldn't change. So all I needed to do was to aim slightly higher than where I wanted to hit on the target, so that the arrow had more distance to fall, and didn't hit the ground before reaching its destination. After realizing I just needed to shoot higher, my shots were much improved.
  23. The Physics in Makeup

    One of the endlessly fascinating things about physics is that it's in literally everything. Makeup is one of my primary hobbies, and I've noticed many aspects of physics in my daily routine. Whether you're using a makeup brush or a makeup sponge to get that flawless finish, you create a lot of friction on your face. In fact, the level of friction you apply will determine the quality of your application. Not enough, and you'll look a patchy mess. Too much, and you probably irritate your skin and defeat the purpose. A perfect balance of friction is what will lead you to a soft blend. Also, density plays a huge roll in makeup. When choosing between kinds of base makeup, from foundation to BB creams to tinted moisturizer, you have to know the kind of look you're going for. The denser the formula, the higher the coverage, and the thicker the finish. On a semi-related beauty note, static electricity is also a common battle in hair. This doesn't affect everyone, but being someone who has thick curly hair, I know too well the pain of having to carry dryer sheets to calm staticy hair. Lastly, every makeup lovers worst fear is gravity. The unfortunate acceleration due to gravity on all objects is never more real than when a compact or favorite pressed pigment slips from your hand and plummets to the ground. Seeing the powder shatter truly is a tragic moment, causing you to curse gravity. Everything is physics, and it can be fun to notice it in simple daily tasks.
  24. Physics Of Avoiding Hypothermia

    Citizens of the Rochester area experienced a weather crisis of dangerous proportion a couple weeks ago, to varying degrees. When I realized the power was down,I was excited for what I assumed would be a temporary break from school, and physics, but was disappointed. My father, being a type-A scientist type, found a way to bless me with the joy of physics even during our dark age adventure. My home had no electricity for days, and therefore no heat. We do, however, have a wood stove with a blower.The blower requires electricity, and my father keeps a deep cell battery for emergencies. So my dad would charge the battery on his car, then plug the stove blower into the battery inside the house. He used a voltmeter to periodically measure the voltage, to watch for when it needed to be recharged. He used this chart, not letting the battery drop past 30%, to be as safe as possible. And boy was I thankful for this battery, as it kept our home warm enough to live in and allowed us to charge out phones. Also, the monitoring of the battery kept my dad busy and out of my hair.
  25. Physics of Fifa

    The game Fifa has a displays many things parallel to physics in reality. In the game, motions of players and the ball as well as wind resistance. When you pass the ball through the air, the game mimics the parabolic path that the ball would take in a real live soccer game. Things such as the wind and the different players striking the ball are all accounted for. If the environment in the game is one of higher winds then different outcomes will occur when a ball travels through the air. Also in the movement of players momentum is heavily considered. If you were to play older Fifa game, the movement of players would seem unrealistic because they would be able to change momentum and accelerate themselves in impossible ways. In the newer games, when a player is moving full speed, it takes time for them to change their direction after having all of that momentum moving in some direction.
  26. Rounder Than Round

    Does everyone remember that day in science class when they told you the Earth was round, and you were like, "Yeah, no duh." And then a couple of years later they told you the Earth was also incredibly smooth, and you kinda just went with it. And then they said if you held an orange and a billiard ball in your hand, and then you could also hold the Earth, that it would feel more like the billiard ball than it would the orange? And that's when you got real confused. What about all the super tall mountains and super deep valleys and the trenches and the oceans? It made sense eventually though that these features were rather small compared to the whole mass of the planet. So now the Earth is one of the smoothest things you can think of. But there actually is one thing on Earth that is the most roundest, smoothest thing to exist on our planet: a ball of silicon. This sphere is officially the roundest thing humans have created; if it were Earth, the distance between its highest and lowest point would be 14 meters. The reason it was created is pretty cool too. The sphere is an attempt to create a substitute fir the current definition of the kilogram, as this measurement is currently dependent on a physical object called "The Big K" that is locked away in some basement in France. The problem is that there is no way to keep this object from being warped over time, and the definition of a kilogram therefore changed. The creators of the silicon sphere hope to use the amount of atoms in that sphere as a new constant that would replace the kilogram.
  27. In the last decade, the uprise of mobile devices with touchscreens has been prominent, and there are 2 main types of touchscreens. The first, and cheaper style, is known as resistive, which uses 2 separated films that when come in contact they allow current to flow. This is what is used to determine the location of the touch, as wherever the current is flowing is where the user is currently touching. The issue with this system is that it requires physical movement of the plates, meaning it can be triggered by anything pushing it together, also if it's layers are no longer even they can touch if nothing is pushing on them, causing unwanted actions. The solution to these issues is the more complicated design, known as capacitive touch. This uses a system of 4 capacitors on each corner, and when the touch occurs, based on how the capacitance changes, the computer system can determine the position of the touch. This is exceptionally useful for avoiding accidental touches, and for creating a much more durable touch surface. Also, it enables much more precision and ease of use to the user, as they don't have to physically move anything, and so there is less to go wrong. The disadvantage of this is that water and anything else conductive greatly reduces the accuracy and usability of such a touch screen, as it messes with the currents. Thanks to this kind of technology, it is much easier for us to use our mobile devices with ease and precision.
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