Analogue Wayback, Ep. 10

Color correction all stems from a slab of beef.

Starting out as an online editor at a production and post facility included working on a regional grocery chain account. The production company had a well-oiled “assembly line” process worked out with the agency in order to crank out 40-80 weekly TV commercials, plus several hundred station dubs. Start on Tuesday shooting product in the studio and recording/mixing tracks. Begin editing at the end of the day and overnight in time for agency review Wednesday morning. Make changes Wednesday afternoon and then copy station dubs overnight. Repeat the process on Thursday for the second round of the week.

The studio product photography involved tabletop recording of packaged product, as well as cooked spreads, such as a holiday turkey, a cooked steak, or an ice cream sundae. There was a chef on contract, so everything was real and edible – no fake stylist food there! Everything was set up on black or white sweep tables or large rolling, flat tables that could be dressed in whatever fashion was needed.

The camera was an RCA TK-45 with a short zoom lens and was mounted on a TV studio camera pedestal. This was prior to the invention of truly portable, self-contained video cameras. For location production, the two-piece TKP-45 was also used. It was tethered to our remote production RV.

This was a collaborative production, where our DP/camera operator handled lighting and the agency producers handled props and styling. The videotape operator handled the recording, camera set-up, and would insert retail price graphics (from art cards and a copy stand camera) during the recording of each take. Agency producers would review, pick takes, and note the timecode on the script. This allowed editors to assemble the spots unsupervised overnight.

Since studio recording was not a daily affair, there was no dedicated VTR operator at first. This duty was shared between the editors and the chief engineer. When I started as an editor, I would also spend one or two days supporting the studio operation. A big task for the VTR operator was camera set-up, aka camera shading. This is the TV studio equivalent to what a DIT might do today. The camera control electronics were located in my room with the videotape recorder, copy stand camera, and small video switcher.

Television cameras feature several video controls. The iris and pedestal knobs (or joysticks) control black level (pedestal) and brightness/exposure (iris). The TK-45 also included a gain switch, which increased sensitivity (0, +3dB, or +6dB), and a knob called black stretch. The latter would stretch the shadow area much like a software shadows slider or a gamma control today. Finally, there were RGB color balance controls for black and white. In normal operation, you would point the camera at a “chip chart” (grayscale chart) and balance RGB so that the image was truly black and white as measured on a waveform scope. The VTR operator/camera shader would set up the camera to the chart and then only adjust pedestal and iris throughout the day. 

Unfortunately not all food – especially raw ham, beef, or a rare steak – looks great under studio lighting nor in the world of NTSC color. Thankfully, RCA had also developed a camera module called the Chromaproc (chroma processor). This was a small module on the camera control unit that allowed you to adjust RGBCMY – the six vectors of the color spectrum. The exact details are hard to find now, but if I remember correctly, there were switches to enable each of the six vector controls. Below that were six accompanying hue control pots, which required a tweaker (small screwdriver) to adjust. When a producer became picky about the exact appearance of a rare steak and whether or not it looked appetizing, then you could flick on the Chromaproc and slightly shift the hues with the tweaker to get a better result. Thus you were “painting” the image.

RCA used this chroma processing technology in their cameras and telecine controls. The company eventually developed a separate product that predated any of the early color correctors, like the Wiz (the original device from which DaVinci was spawned). In addition to RGB color balance of the lift/gamma/gain ranges, you could further tweak the saturation and hue of these six vectors, which we now refer to as secondary color correction. The missing ingredients were memory, recall, and list management, which were added by the subsequent developers in their own products. This latter augmentation led to high-profile patent lawsuits, which have now largely been forgotten.

And so when I talk about color correction to folks, I’ll often tell them that everything I know about it was learned by shading product shots for grocery commercials!

©2022 Oliver Peters