Video Acquisition

Nicholas Brennan

Texas A&M University

Jean-Francois Chamberland

Texas A&M University

Gregory Huff

Texas A&M University

Table of Contents

Panasonic AG-HPX170P Camcorder
Operation Checklist (tripod, indoors)
Basic Operations (miscellaneous environments)
Pan the Camera Slowly

The instructions contained in this tutorial are intentionally concise and accessible. They are meant to guide the neophyte through the footage acquisition process when the ultimate objective is the creation of video tutorials and short presentations. Many of the techniques and tradeoffs associated with filming are disregarded in favor of a straightforward exposition. This, hopefully, will decrease the overhead associated with becoming familiar with the equipment and, thereby, entice candidates to embrace digital media.

Panasonic AG-HPX170P Camcorder

The HPX170P is nimble and accessible. It can produce quality footage in a format that can be edited efficiently. This tutorial acts as a good starting point for the operation of this Panasonic camcorder. Following guidelines and understanding the fundamentals of digital video will ensure the acquisition of high-quality clips.

Operation Checklist (tripod, indoors)

The checklist is the most basic procedure that a new user should follow to begin filming in an indoor, well-lit environment. This series of steps assumes that the user has already checked out blank P2 cards along with a Panasonic HPX170P camcorder. There is a video companion (high quality, low quality) to this checklist; an efficient strategy is to follow the steps featured on the video during the setup procedure.

  1. Insert charged battery or connect power cord.
  2. Insert P2 cards: lift ViewFinder, open slot cover, push and lock P2 cards.
  3. Turn on camcorder.
  4. Open LCD display and remove lens cover.
  5. Toggle mode to MCR and format P2 cards, if needed.
  6. Toggle mode back to CAM and select proper P2 slot for recording.
  7. Select manual mode on AUTO/MANUAL switch.
  8. Set FOCUS to manual (M).
  9. Set ND FILTER to OFF.
  10. Engage ZOOM SERVO.
  11. Select low (L) GAIN.
  12. Set WHITE BAL switch to A.
  13. Set RING to FOCUS.
  14. Verify settings on LCD display: HD720P, 30:30P, ALC, remaining minutes and battery charge.
  15. Turn SHUTTER OFF.
  16. Turn optical image stabilizer (OIS) OFF for tripod use.
  17. SELECT audio CHannels, phantom power INPUTs and adjust AUDIO faders.
  18. Connect microphones and switch corresponding inputs to MIC.
  19. Adjust white balance (AWB) over white background.
  20. The camera is now ready to record.

Basic Operations (miscellaneous environments)

More experienced users may want to go beyond the simple checklist to create particular cinematographic effects. In this case, a more in-depth understanding of individual aspects of video acquisition may be needed. This section offers a brief overview in this direction.

The Panasonic HPX170P camera features a switch labeled AUTO/MANUAL; the automatic mode simplifies its operation significantly. This is especially useful when one must grab the camera and start shooting immediately, with little time to adjust parameters. When engaged, the AUTO mode will take precedence over several functions, including the ones listed below.

  1. A. Iris: auto-iris.
  2. AGC: automatic gain control.
  3. ATW: automatic tracking of white balance.
  4. AF: autofocus.

The automatic mode will ensure an appropriate level of video quality, although not necessarily the clarity of image achieved through proper tuning of manual settings. When in an extreme hurry, one may elect to go through the following instructions to begin the footage acquisition process promptly.

  1. Set the power switch to ON.
  2. Press the side of the card slot cover and slide the cover to open it. Insert P2 cards securely. Push the P2 card eject button to the right and close the card slot cover.
  3. Switch the AUTO/MANUAL switch to AUTO.
  4. Set the ZOOM button to SERVO.
  5. Press the START/STOP button to record.

Nevertheless, this is not the preferred mode of operation. The diligent user should plan ahead and go through manual settings carefully, as explained in the checklist above.

Manual Recording Setup

Selecting the various camcorder options manually, when done properly, will yield crisp and clear footage. Parameters can even be tailored to the creation of specific cinematographic effects. The basic settings discussed below are tailored to shooting a short video within a controlled and well-lit indoor environment. Additional details are provided to enable the user to understand potential tradeoffs and make educated decisions about the operation of the camcorder.

  1. Switch the AUTO/MANUAL switch to MANUAL.
  2. Set the ZOOM button to MANUAL.
  3. Use the optical image stabilizer (OIS) to reduce the effects of camera shake when shooting by hand. On the other hand, when using a tripod, turn the OIS function off for more natural images. If two P2 cards are inserted, the SLOT SEL button offers a one-touch mechanism to select the slot whose card will be employed as the recording media.

Recording Format

The pictures that are acquired in all digital recording format are stored in pixel arrays. A frame rate of 30 frames per second (fps) is adequate for Internet streaming. At this rate, clips offer a temporal feel similar to motion picture film without introducing undesirable artifacts. The favored option for shooting short videos depends on the intended quality of the stream and its potential application. For standard presentation, we suggest the following format.

In high-definition DVCPRO-HD, the preferred shooting mode is 720P/30PN. This mode uses twice as many pixels and better color resolution per pixel to record its frames, as compared to standard definition video. Using the REC FORMAT function on the RECORDING SETUP screen, select 720P/30NP as the recording format. For action scenes and project demonstrations, a faster frame rate may be required. The recording time in 720P native 30 fps is approximately 128 minutes on a 64 GB P2 card.

White Balance

Proper white balance is essential to faithfully record the colors in a scene. The camcorder can be white-balanced in different ways. If the WHITE BAL switch is set to PRST, then the AWB button on the front of the camera can be used to toggle between P3.2K (indoors) and P5.6K (outdoors). For more control, manual white balance is required. The two channels function identically. After zooming onto a white card, set the WHITE BAL switch to A, press and hold the AWB switch until the camera displays AWB Ach ACTIVE. Any time the light condition changes, the white balance needs to be calibrated again. This is likely the most desirable option for stable lighting conditions. Another approach is to set the WHITE BAL option to ATW in the SW MODE menu. For example, one can configure the camcorder so that B is set to ATW. Then, when the WHITE BAL switch is moved to position B, the camera automatically start to track white balance.

Camera Settings

  1. IRIS: Aperture affects the depth of field. The iris dial sets the f-stop manually and the iris button is used to toggle between auto-iris and manual mode. The f-stop of an optical system is the ratio of the lens's focal length to the diameter of the entrance pupil. It is a dimensionless number that is a quantitative measure of the maximum aperture diameter of a lens. A lens with a larger maximum aperture is a fast lens because it delivers more light intensity to the focal plane, allowing a faster shutter speed. Lenses often perform at their sharpest in a certain f-stop range, e.g., two stops down from wide-open to two stops up from fully-closed. Moreover, the issue of diffraction comes into play when the aperture is too small; this makes the image out of focus. A shallow depth of field is unnecessary for short video presentations and, as such, a relatively small aperture can be selected (f/5.6).
  2. SHUTTER: The shutter speed affects motion blur and can be employed to control exposure, but not without side effects. Fast moving objects, low-light conditions and advanced cinematographical effects may demand special adjustments. Yet in most circumstances, the default shutter speeds will results in normal-looking video footage. To avoid the idiosyncrasies associated with computer monitors and flickering lights, a proper shutter speed in the USA is typically 1/60.
  3. INPUT 1/ INPUT 2: When microphones are plugged in the XMR connectors, the two LINE/MIC switches should indicate MIC. These switches control the signal level sensitivity of the connectors. For instance, the Sennheiser lavalier microphone and the Panasonic unidirectional microphone both require the MIC setting.
  4. FOCUS: The FOCUS switch has three settings: A, M and infinity. This switch controls the capabilities of the autofocus on the camera. Under A, the camera operates in full autofocus mode, automatically seeking the best position. While in M mode, the focus must be changed manually by the operator. Finally, the infinity position instantly adjusts the camera so that far objects are in sharp focus. Note that autofocus works better under faster frame rates and brightly lit conditions.
  5. PUSH AUTO: While in manual mode, it is possible to invoke the autofocus system on a temporary basis by pressing and holding the PUSH AUTO button. When this button is released, the camera reverts to manual focus mode.
  6. ND FILTER: The neutral density filters can be employed to lower brightness in bright conditions. While shooting indoors, it may be turned off.
  7. GAIN: The gain filter is an electronic amplification of the video signal. It makes the picture look brighter, but also introduces noise into the picture. The low gain setting should be selected in typical, well-lit conditions.

Audio Channels

While shooting, one can record up to four channels of sound. When the DVCPRO HD form is selected, the recording mode is fixed to 4-channel recording.

  1. To use the Panasonic unidirectional microphone, set CH1 SELECT to INPUT 1 and turn on the corresponding MIC POWER +48V switch to ON.
  2. Similarly, to use the Sennheiser lavalier microphone through the XLR 3-pin terminal, set CH2 SELECT to INPUT2. Also, make sure that the MIC POWER+48 switches are OFF.

The AUDIO LEVEL knobs can be used to adjust the recording level of the built-in microphones or external audio equipment. Refer to the audio level meter at the bottom left of the viewfinder and LCD monitor to find proper settings.

Playback Operations

To employ the playback operation, press the mode button until the MCR light turns on. Video data created on the P2 card in one uninterrupted shooting session is called a clip. While in MCR mode, clips will be displayed on the LCD screen as thumbnails. To play back a clip, select the desired thumbnail and push the operation lever in the play direction or use the remote control. Notice: Only clips recorded in the same format as the playback format (shown at the bottom of the screen) can be played back.

Extraneous Information

Some modalities of the camcorder can be used with SD memory cards. SD memory cards from 512 MB up to 16 GB can be used with this camcorder. Be sure to format the cards with the HPX170P camera; this can be performed in MCR mode under the OPERATION menu.

Pan the Camera Slowly

The numbers below are inspired by recommendations from the American Society of Cinematographers . This table stresses how slow the camera should move to achieve smooth motion. In many situations, it may be best to use a static setting.

Table 1. Execution Time for 90-degree Pan
Zoom 24p 30p
Z00/4.2mm 15 seconds 11 seconds
Z20/6mm 15 seconds 14 seconds
Z36/8mm 23 seconds 20 seconds
Z84/30mm 80 seconds 60 seconds

The chart states that, if the lens focal length is set to 6 millimeter, a user should take 18 seconds to pan 90 degrees with no juddering or stutter when shooting 24p.