The other night I was out filming traffic. I ended up getting a really weird camera artifact. It looks like a dark bar that rolls through the shot from bottom to top. At first it made me freak out a bit, thinking that the camera was somehow broken. I eventually figured out that it is the result of A) a flickering light source and B) the right (wrong) shutter speed. I think the streetlights were tungsten bulbs, but they may have been HID bulbs. Whatever they were they definitely had a flicker to them.
I read somewhere that ideally you should shoot a shutter speed that is double the frame rate. This gives you a 180 degree shutter and it should look very similar to film. The way that I made these bars appear was by changing the shutter speed away from 1/125 when I was shooting 720p60. I have ideas as to why this creates the banding, but they are all theories. If you have any more insight pleas tell me in the comments! Moral of the story: keep the shutter speed at twice the frames per second. Change the aperture, or buy a faster lens!
I can only hope that there will be a lot of other happy people unwrapping new cameras this christmas. I bought my 7d about a month ago, and the best/worst thing is that now I realize buying it is just the beginning. I want to buy sooo much gear to use with it, and it is tough to find well recommended, modestly priced gear. Here is the short list of what I have or want to buy, to wet your creative whistle.
bogen tripod with fluid head.
If you buy nothing else on this list, get a tripod and a fluid head. The 5d/7d do not have ANY image stabilization capabilities, so if you plan on using any lens longer than a 50 you will need to use a tripod. The fluid head is also critical because many other types of heads are built for still photos. They are easily adjustable, but not in smooth movements. A fluid head is designed for video, and is the only real way to get a smooth pan.
Ever since I have fallen in love with the Canon 7d dslr, I have been fantasizing about making a legit follow focus for a dslr. It allows you to have more control over the focusing, and a smoother camera because your rotation is in a different axis as the lens. (You may hear more of my traditional FF plans in a few) In the meantime I saw a vimeo clip that had this little gem of an idea in it. For quick focus pulls a lever like this can’t be beat, and it’s dirt cheap as well!
Here are all of the parts from the old home depot. Simple stuff. It totaled around $6, and it’s enough to make 2 and have parts left over.
The first step is to cut out a few teeth in order to make room for the bolt.
After seeing this project from cibomahto a while ago, I finally got my act together and bought a $1 IR led from radio$hack so I could build an intervalometer for my SLR.
For those who don’t know an intervalometer is, it tells your computer to take a picture every given interval. This enables you to shoot video with a still camera over a long period of time. Sometimes you have two intervals on fancy ones. Those allow you to use the bulb setting on your camera. Right now it has two potentiometers to indicate seconds and minutes between shots. It is run from a nine volt battery, and I expect it to have fairly good battery life. Only time will tell. The IR LED can’t take too much juice! It has a status led to show when it is firing (for trouble shooting) and not a whole lot else.
This currently needs a housing and a interface. I am debating the merits of a small lcd vs just using a printed label to mark the pot positions. It’s pretty much spray and pray right now. At least it is adjustable!
arduino d40 ir intervalometer
I’m thinking about getting one of these and eliminating the pots completely.
lcd shield from nuelectronics.com
Which would end up making my project very similar to this one but for a nikon.
One last thought is possibly adding the functionality to use the bulb setting and then add a bracketing ability. Isn’t technology wonderful!
I had a lot of time to kill over break, so I shot a bunch of timelapses. Here they are!
This is from a coffeeshop that I spent a lot of my time in.
This is of some clouds at dusk. This one has two separate positions, and it is really interesting to see the color shift towards the end of the video. I also have it on auto-something(ISO?), so it isn’t very consistent frame to frame.
Here’s two quick video related snafu’s I’ve run into today.
I have had to unserialize a copy of FCP and then put in a new (the correct one, technically) serial number. It turns out that unless you want to reinstall everything, then the file to find is located in Library/Application Support/ProApps and it is called “Final Cut Studio System ID” Delete it with fcp closed, and then open it up again Continue reading →