In the third part of my S-Log series, I took the Sony F3 outside on a nice bright day to show what S-Log can do. Jeff Lee and I headed up to the roof of AbelCine and found some shade to stand in; this allowed us to show the most contrast possible. I shot the blog in S-Log, as well as in the standard video modes with the AbelRange profile that I created earlier this year. This way I could show just what S-Log enables in the camera. All the clips in the video, except the last one, were recorded to the Gemini 4:4:4 recorder, which records in uncompressed DPX stacks so nothing was lost along the way. The last shot was S-Log out to a PIX240 recorder in ProRes422 HQ, which was enabled with the new F3 1.31 firmware from Sony.

I graded all of the shots in DaVinci Resolve Lite. The difference between S-Log and my range profile can be slight at times, but pay close attention to highlight areas, especially the skin highlights. Thanks to Isaac Kiener from Sales for helping out. Stay tuned for the last part of the series on look up tables in the camera.

To learn more about the F3, S-Log and LUTs make sure to check out our F3 Training Class in NY and LA.

I often get asked about the stuttering video motion, or judder, seen in 24p video. Even though we have all been watching or shooting 24p for years, for many of us it is new to see true 24p (or 23.98p) video displayed on a monitor.

24p is ‘jumpy’ by its nature, but the look of 24p video in a digital video camera can still come across a little more ‘jumpy’ then you’d expect. There are several reasons for this, which I explain in article for HDVideoPro magazine called “Did I Judder.” As part of the article, I put together these two videos to show the difference between native 24p video and 24p converted to 60i. I did this because much of the 24p content we see has been converted to 60i already, which has a smoothing effect that is very noticeable on television.

…continue reading 24p Judder and 60i Conversion

If you’ve been following my HD Formats series (Video Formats, Bit Depth & Bit Rate), this blog should help clarify a couple more of those words and numbers we see associated with HD video formats. First, I’ll talk about different color models in the HD world, which are often shown as ‘Y Cb Cr’, ‘Y Pb Pr’ or ‘RGB’. Then I’ll cover color sub-sampling, which is most often described by a combination of numbers such as 4:2:2 or 4:2:0. These two terms are closely associated with one another, but have very different implications.

Let’s start by looking at two HD formats, each with a different color space and sampling. On the new PMW-F3 camera, you can record internally in the XDCAM EX format, but also output an S-Log RGB signal over Dual-Link or 3G SDI. More specifically in 1080 24p,

XDCAM EX =  8-bit YCbCr 4:2:0 1920 x 1080 23.98p recording (35 Mb/s recorded)

S-Log RGB = 10-bit RGB 4:4:4 1920 x 1080 23.98Psf (Uncompressed)

The text in red describes the color model, and the text in blue describes the color sub-sampling. Here is a short description of both.

…continue reading HD Formats: Color Model & Color Sub-Sampling

OConnor has a new labs section of their website, and they have been posting some great articles. In their article, Rod Standards Explained, they diagram the different standards for rod spacing that have developed over the years. This is an important read for anyone considering a new mattebox or baseplate system. Additionally they put together a chart with lens diameters of popular cinema lenses. Both of these articles are important resources, so visit OConnor Labs today.

It occurred to us when creating the Camera Mounted Recorders comparison chart that there is often confusion around different HD formats. In 2009, I wrote up a blog titled Making Sense of HD Formats that covered the different HD formats used today. But what I didn’t go into was those other words and numbers that we often see associated with a video compression format: bit rate and bit depth. Don’t stop reading just yet, I promise to keep this simple and you’ll see that these numbers may actually mean something when it comes to your next production.

Most professional HD video cameras today have an HD-SDI (High Definition – Serial Digital Interface) output, so this will be a good place to start the discussion. An example of a typical HD-SDI video output would be a 1080 60i Uncompressed 10-bit signal. If you are scratching your head already, let’s break it down a bit with a couple definitions.

…continue reading HD Formats: Bit Rate vs Bit Depth

A few weeks ago, Jesse Rosen wrote an article explaining the technical definition of LOG-encoded video and how it differs from a viewing gamma such as REC709. To better understand how you might use LOG capture in production, I shot this video illustrating the differences.

REC709 is a monitoring standard for a final image; it is the contrast and color that generally replicates what you see to eye. But, it doesn’t necessarily show everything the camera’s sensor is capable of capturing. With the latest wave of Digital Cinema cameras, such as the ARRI ALEXA, the Dynamic Range detectable by our shooting devices has expanded dramatically, approaching that of film and pushing past what REC709 is capable of showing. To capture the imaging capabilities of these latest generation sensors, a LOG gamma can be used.

There are many situations where you do not have full control over lighting conditions, such as a bright window in the background or a city street at night. Even with full control, it is still common to color correct a project once it is edited together. If the image is captured in REC709, the ability to adjust the final image is limited by the contrast range already imposed on the image. LOG is a flatter contrast, allowing far greater image manipulation. Take a look at the video to get a sense of the difference.

Our eyes perceive brightness differently than an electronic sensor does. Video monitors are locked into a standard for color and contrast, but now Digital Cinema camera systems are being used to capture images that are used and displayed in media that can see well beyond those limitations. Brightness is captured on a Linear scale (LIN), and usually stored with video gamma (REC709) or with a more film-like Logarithmic encoding (LOG). What does this mean, how does one use it, and what capabilities does it represent?

In the first of a series of Technical Resource articles and CineTechnica posts, I present an introduction to the concept of LOG, its origins and capabilities. Click here for the article.