Illustration anamorph letterbox by Jailbird via Wikipedia

The anamorphic isn’t using letter boxing or black banding on an image, but instead an optical method is used. An anamorphic lens is a lens with convex glass that horizontally squeezes images down from a 2.35:1 widescreen aspect ratio to a 4:3 ratio. Projectors need have the same style lens in order to properly project the image. If you’ve seen a movie that has “Filmed in Panavision” during the credits, you’ve seen a movie shot in the anamorphic format.

Digital video cameras have a feature called “squeeze mode” which simulates an anamorphic lens. The image quality will suffer slightly because of this, but depending on your output format, the difference might be negligible. We will have a few videos about this later this week.

Unraveled by gak via Flickr

This week, we talk about the differences between approaching an audio editing session and a video editing session. Rob and Chris have worked with and edited both, but each has their specialty. This week they have a candid discussion about the differences they see in the philosophy of editing audio and editing video. Learning the differences between the different approaches is key to understanding the basics.

Discussed links:
WNYC’s Radio Lab
The Travel Channel’s Anthony Bourdain’s No Reservations
Fox’s Lie to Me on Hulu
CCD on Facebook
Chris Cavs on the Word on the Tweet podcast
Rob Blatt featured on the Disqus blog

IMG_1591 by fuxoft via Flickr

Interlaced signals are broken up into alternating fields. The upper and lower fields each shows half of the total video frame. Each field is shown for half of the time a frame is shown. So 1 frame of interlaced video has two different fields that display the upper and then lower fields. Progressive signals are full frame images, so when you see one frame of a progressive signal, it’s the entire image in a single frame.

The interlaced signal was invented by Leon Theremin, who also invented the musical instrument that shares his last name in the 1927. Interlaced was the only standard in town for television until 1993, then the FCC tested the first broadcast progressive system. Progressive monitors had been around for a few decades thanks to computer monitors before being adopted into the television world.

Here’s an animated graphic to assist in understanding how interlaced systems display images:

Here are some more resources for learning about interlaced vs progressive:

• The Big Picture – Interlaced vs. Progressive, Fields vs. Frames – http://www.animemusicvideos.org/guides/avtech/video2.htm
• Interlaced vs Progressive Signals – http://hubpages.com/hub/interlaced-vs-progressive
• Wikipedia: Interlace – http://en.wikipedia.org/wiki/Interlace

Pixels -Reprise- by solidxsnake13224 via Flickr

When is a pixel not a pixel?

Like your TV, computer and movie screens, pixels have aspect ratios too. Not to be confused with picture aspect ratio, pixel aspect ratio deal with the shape of pixels. Early analog television was made of pixels that were square, but when the digital video standard was created, DV pixels are non-square. When the high definition standard was created, the standard was set back to square pixels. Confused yet?

All non-linear editing software can convert square pixels to non-square pixels and the other way as well. While video professionals (read: Chris) don’t have to think twice about this setting, it’s awfully confusing to those who aren’t as well versed with video editing (read: Rob).

So what is the difference? That’s what we’ll be discussing on this week’s show.

Resources:
Pixel Aspect Ratio Calculator – http://www.digitalrebellion.com/pixel_calc.htm
A Quick Guide to Digital Video Resolution and Aspect Ratio Conversions – http://lipas.uwasa.fi/~f76998/video/conversion
Artbeats’ Pixel Aspect Ratio, Part 1 – http://www.artbeats.com/articles/86

DSCN0593-c2b4s3 by 12fh

HD and HDV are both high definition video formats. Instead of playback formats, HD and HDV are recording formats. HD describes an image that is 1920×1080 or 1280×720 pixel images. HDV describes an image that uses rectangular pixels at a size of 1440×1080 that displays the same size as a 1920×1080 square pixel image (The pixels are 1.33 times wider than an HD pixel).

Bit rates vary between the two also, HDV has a bit rate of as high as half and as low as a quarter of an HD bit rate. Both formats use compression, but HDV uses interpolation and groups of pictures (gops) to create the necessary compression. HD also uses compression, but you have an option as to what kind of CoDec you want to use.

Video Cameras by Rob Blatt

Video cameras can range from a hundred dollars to hundreds of thousands of dollars. The components vary in quality and price. Chris brings up four questions that you should ask yourself when you are thinking about buying a camera.

Note: We reference some topics discussed in episode nine How Video Cameras Work, but it’s not necessary to listen in order to understand this week’s show.

Review recommendations
CNET Reviews is always a good starting place
Photo.net is one of the best sites for anything photo related.
camcorderinfo.comhas some good reviews & comparisons

100_1692 by lergik

Video compression is different from file compression because it is a “lossy” compression, meaning you can not get the original video back once it’s compressed.

There are many factors that go into how a video is compressed, some factors are video resolution, frame rate, bit rate, codec and file format. This doesn’t include how the video is shot, just the hard decisions that come with shooting video. On the image acquisition side of things, lighting, camera movement and framing can all have an effect on file size and compression.