PXL-2000

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The Fisher-Price PXL-2000 (also known as the PixelVision by Fisher-Price, and the KiddieCorder by some of its fans) was a toy black-and-white camcorder produced in 1987 that used an ordinary compact audio cassette as its recording medium.

When the PXL-2000 was available in retail outlets, it came in two versions—one with just the camera and necessary accessories (power supply, blank tape, etc.), and another which came packaged with a portable black and white television with a 4.5 in (114.3 mm) diagonal screen, for use as a monitor. There were also extra accessories sold separately, such as a carrying case.

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[edit] Technical information

The PXL-2000 consisted of a simple aspherical lens, an infrared filter, a CCD image sensor, a custom ASIC (the Sanyo LA 7306M), and an audio cassette mechanism. This was mounted in a plastic housing with a bay for consumable batteries and a simple RF video modulator. A plastic viewfinder and some control buttons completed the makeup of the device itself.

The fixed-focus, aspherical lens was actually of quite reasonable quality, and does not significantly differ from that found on many modern low-end digital cameras.

An ordinary cassette transport was used for storage of both audio and video. The PXL-2000 could store 11 minutes of shooting by moving the tape at a high speed, roughly 16 7/8 in/s (429 mm/s) as opposed to cassette's standard speed of 1 7/8 in/s (48 mm/s) on a C90 CrO2 (chromium dioxide) cassette. The high speed is necessary because video requires a wider bandwidth than standard audio recording (In magnetic tape recording, the faster the recording speed, the more bandwidth can be recorded on the tape). The PXL-2000 records the video information on the left audio channel of the cassette, and the audio on the right. [1]

In order to reduce the amount of information recorded on the tape to fit within the narrow confines of even a revved up audio cassette, it used an ASIC to generate slower video timings than conventional TVs use. It scanned the 90 by 120 pixel CCD fifteen times a second, feeding the results through a filtering network, and then to both a frequency modulation circuit driving the left channel of the cassette head and to an ADC, which fed the framestore.

The ASIC connected the digital output of the ADC to a block containing a digital framestore capable of storing two frames of video at the resolution of the image sensor. While one frame was being gradually read out of the CCD into the first framestore section, a previous frame would be scanned out of the second framestore section at full TV frequency. The ASIC was also responsible for generating control signals for the CCD image sensor, and for generating automatic gain control (AGC) signals.

The PXL scanned its 120 by 90 CCD fifteen times a second, meaning that it processed 162000 pixels per second ignoring recovery time; the CCD clocks actually ran at approximately 180kHz. It ran its tape approximately nine times faster than an audio cassette, giving approximately 160kHz of useful bandwidth. This meant that, assuming the tape behaved at specification, it would record only half of the information scanned out of the CCD. With this in mind, the PXL ASIC applied fairly heavy analogue filtering to the video signal to smooth it on exit from the CCD, then pre-emphasize it, offsetting the disproportionate loss of higher frequencies.

For playback and view-through purposes, circuitry was included that could take image data from either the cassette or the CCD and use it to fill the framestore at the PXL reduced rate, while scanning other half of the framestore at NTSC rates. Since each frame in the ping-pong framestore included only 10800 pixels in its 120 by 90 array, the same as the CCD, the results were deemed to be marginal at best, and black borders were added around the picture, squashing the framestore image content into the middle of the frame, preserving precious pixels which would otherwise be lost in overscan. An anti-aliasing low-pass filter was included in the final video output circuit.

The PXL-2000 today suffers from reliability problems associated chiefly with its cheap construction and somewhat abusive users. The most common faults are decayed drive belts- common to most tape mechanisms of the 1980s- and fogged blue filters. The blue filter is a glass optical component that was fitted behind the lens to prevent infrared light from reaching the CCD and producing confusingly miscoloured images. They tend to become fogged in stored PXLs, possibly as a result of outgassing from the plastic components of the camera. Many PXL-2000s have also suffered damage from leaking electrolyte from batteries that were never removed, but this is usually not serious and can be easily repaired. Cameras left with tapes inserted for long periods of time may also need the tape path to be cleaned and a pinch wheel replacement.

[edit] Simulating the PXL-2000

Oddly, simulating the PXL's simple hybrid design turns out to be quite difficult. Indeed, getting the cassette deck distortion just right has proven to be an extremely complex problem. One can, however, get close to the PXL's oddly ethereal quality by putting a video sequence through a number of different processing steps. These must be carried out in this order or the effect will be quite different.

  • Reduce the saturation to 0. The PXL-2000 is a monochrome camera.
  • Reduce the frame rate to 15 frames per second. Deinterlace the video; the PXL does not interlace.
  • Reduce the resolution to 120 pixels by 90 pixels.
  • Apply a Gaussian blur function with a radius of about one and a half pixels. This mimics the lowpass filter.
  • Sharpen the image slightly (about 30%).
  • Clamp the black point to about 5% and the white point to about 95%.
  • Compress the dynamic range of the entire image by about 1.2 to 1.
  • Posterize to 90 steps
  • Add a lag effect; this should add a small proportion of the three previous frames to each frame, giving slight trails and motion artifacting
  • Add whichever video modulator simulation effect you prefer, plus some scanlines (since PXL is not interlaced)
  • Clamp the white and black points again
  • Apply a second Gaussian blur with the same radius
  • Add a black border around the image to push the edges of the image into the title safe area.

The result of this process should resemble PXL-2000 video.

[edit] Revival in popularity

The PXL-2000 has seen a revival in popularity since the early-to-mid 90s among independent, experimental/avant-garde, and underground filmmakers, due to its unique low-resolution pixelated black & white image, with a lower frame rate of around 15 frames/s, akin to 8 mm or super 8 movie film (upconverted to the standard 30 frames/s in the camera). The image is also "gutterboxed", meaning it has a black border around all sides of the picture.

PXL-2000 cameras are still popular in the filmmaking scene—in fact, some individuals offer modifications for the PXL-2000 to output composite video (the PXL-2000 only has an RF output selectable to either US television channel 3 or 4 in its unmodified stock condition), to interface to an external camcorder with a composite video in, or a VCR. The cameras themselves are still in demand, fetching prices as high as $200–500 on auction sites like eBay.

An image of a PXL-2000 camera can be seen here: [1]

[edit] Package Descriptions

[edit] Model #3300 PXL2000 Camcorder

  • PXL2000 Camcoder
  • Mini bipod stand
  • Video switch box
  • Video Cable
  • One PXL2000 audio cassette tape
  • Instruction Booklet
  • 6 "AA" Duracell


[edit] Model #3305 PXL2000 Camcorder Deluxe System

  • PXL2000 Camcoder
  • Mini bipod stand
  • Video switch box
  • Video Cable
  • One PXL2000 audio cassette tape
  • Instruction Booklet
  • 4.5" diagonal black and white TV (with AC adaptor)
  • 6 "AA" Duracell

[edit] Famous uses

The PXL-2000 was used by Richard Linklater in his 1991 debut film Slacker, during the bar scene.

Filmmaker Sadie Benning has also used the PXL 2000 in some of her video works.

It was also used by Michael Almereyda for three of his films: the 1992 film Another Girl Another Planet, which was entirely shot with a PXL-2000, his 1993 short Aliens, and his 1994 film Nadja, in which the PXL-2000 was used for point of view shots of the title character. Ethan Hawke's character in Hamlet can also be seen with one.

See also: :Category:Films shot in PixelVision

[edit] See also

[edit] External links

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