By John Henshall

The game could soon be up for low-resolution digital stills cameras.

What chance would a brick-like camera with a fixed lens, limited fixed storage and no means of checking the captured images have against a sleek product with a 10-to-1 zoom-macro lens, 20-to-1 with digital doubling, two colour LCD screens for both capture and replay, a 25 fps motor drive, removable media capable of recording 90,000 images, the ability to record digital stereo sound and a processing time of less than two seconds per shot?

This isn't a dream of the future. It's now.

Digital imaging is often regarded as truly instant photography. There's no doubting its convenience if you need just one or two images in a hurry but it takes almost as long to upload a camera-full of images via the computer's serial port as to pop into the High Street minilab and put a roll of thirty six through the one hour service.

I have cheered the advent of many low-resolution digital cameras in these pages, not because they will displace our Nikons, Hasselblads and Sinars but because each development brings new digital facilities to some professional niche and keeps us aware of and receptive to the way things are going. And it's often the seemingly amateur devices which tempt and inspire professionals to try things new. In fact, it's strange but true that the majority of enquiries I receive daily from professionals relate to such lower-cost, lower-performance products. These are the products which professionals use to dip their toes in the digital water to gain experience without risk.

Sony DCR-OC7E Digital CamcorderBut, although innovation has abounded, not one product has learned enough from the mistakes of others not to make similar mistakes of its own. Who would have thought it possible that, two years after the advent of the first digital camera with a colour LCD screen we would still see cameras which have an unshaded, power-hungry LCD screen as the only means of composing a shot? Yet the camera described in the opening paragraph is available right now - the Sony DCR-PC7E.

I have mentioned this camera before but now comes the time to tell you about a development which makes acquiring images from such digital video cameras very fast indeed.

The system is called FireWire, and it looks set to replace SCSI as the new super-fast super-easy standard by which peripheral devices such as digital cameras, scanners and printers communicate to their host computers. It is likely to be built into many computers from next year.

FireWire - also known as IEEE 1394 - overcomes most of the idiosyncracies which beset SCSI. Unlike SCSI, it is 'hot pluggable', which means that the computer does not need to be powered down when devices are being connected or disconnected. It does not need terminators, device IDs or heavy multi-cored cables. It uses only a thin flexible cable to carry all the data - up to 200 megabits per second, or 25 megabytes per second - enough for broadcast video. DV camcorders compress the signals and need only 3.6 megabytes per second for video, stereo audio, time code and commands - well within its capabilities. Everything travels down the one FireWire cable - separate sound cables are not required. You can easily daisy-chain devices at the same time, so that they can be shared. In fact the main limitation is the length of link between devices of 14 feet (4.5 metres). But with up to 63 devices connected and acting as repeaters, FireWire could reach nearly three hundred metres.

Radius FireWire Card for PCI MacintoshYou can take advantage of FireWire right now if you have a camcorder with a FireWire output. Radius make the FireWire card which comes with a special cable needed to connect the camera to the computer and PhotoDV software - a Photoshop import plug-in which controls the camcorder from the computer.

You will need a PCI Macintosh or clone running MacOS 7.6.1 or later, QuickTime 2.5 or later and Adobe Photoshop 3.0.5 or later or MicroFrontier ColorIt! 3.2.2 or later. I use a Power Macintosh 8600/250. Installation of the FireWire card and software is no more than a five minute job. In fact, I was grabbing frames from my camcorder well within five minutes of opening the box.

Under the preview window in the Photoshop plug-in is a slider enabling you to set the preview image in one of three positions, from Faster to Sharper. I find the computer fast enough to use Sharper at all times. Below this are buttons for remote camcorder control of normal Play, Search (for next shot change), Fast Forward and Rewind (at 12x speed with picture - in effect searching 300 digital images per second or 90,000 in five minutes), Slow play forward and reverse at one-tenth speed (2.5 frames per second), and Step (one frame at a time) in both forward and reverse. Under this, the precise frame-accurate time code is displayed in hours, minutes seconds and twenty-fifths of a second. It is thus possible to return to any precise frame. Time and date of recording can also be displayed in this box.

Important Note: To view the Screengrab below at its full resolution, download it by dragging it to your desktop and then open it in your own imaging program.

Radius PhotoDV 'Acquire' Screen

On the left is selection for both PAL (625 lines 25 frames per second used in Europe) and NTSC (525 lines 30 frames per second used in USA and Japan) and also for aspect ratio - 4:3 (1.33:1) and widescreen 16:9. Capture can be set to One shot, Multiple shots (to save time re-selecting the plug-in) or Auto every 'x' seconds until 'y' images have been captured - useful for time-lapse. Capture size can be set to 680x510 (square) pixels, 680x544 (rectangular) pixels, 720x576 (the raw image from the camera), or interpolated up to 1024x768 pixels.

The final control is over de-interlacing to reduce the motion artifacts between the two 'fields' (half 'frames') which are interlaced together to make up a television 'frame'.

Bill Gate$


The system is so simple, effective and fast to use that it makes you never want to go back to using a low resolution digital still camera with slow serial interface. I had 90,000+ images of Bill Gates to choose from on a 63 minute tape but it took me less than six minutes to search them all for the best picture of him smiling. I know no other way to search such an extensive resource so quickly.


By way of comparison, I have acquired the same frame of video in three ways. First the conventional way, as a 'composite' video signal; second the slightly better method, as an S-Video signal; and finally using Radius PhotoDV to capture the digital signal direct from the camera. Although capturing images in S-Video avoids PAL colour 'bleed', the biggest improvement in quality is seen when capturing the picture by direct digital means.

Test picture showing selected detail

The original image showing the selected test area on the right (boxed)

Left: Composite Video Centre: S-Video Right: Radius PhotoDV


I now use the small Sony DCR-PC7E camcorder as a video notebook. It does not give the best DV picture quality but it is the most convenient to carry around the world. Take a look at the page which describes my recent sessions at Seybold San Francisco (http://www.epicentre.co.uk/seminars/seyboldsf.html) where you will find small images of each of my fourteen guest speakers. They are all action shots which would have required a very attentive stills photographer - but all I did was put the camcorder on a tabletop tripod and leave it running during the sessions. I captured the still images later using PhotoDV.

Image acquired by Radius PhotoDV Image acquired by Radius PhotoDVImage acquired by Radius PhotoDV Image acquired by Radius PhotoDV

A selection of images taken on the Sony DCR-PC7E digital camcorder and acquired by FireWire using Radius PhotoDV software.

Although I end here for the moment the facilities offered by FireWire, Radius and others do not. Radius MotoDV is stand-alone software which allows the acquisition of moving images from the camcorder, in real time, by FireWire. And the hot news is that Radius are about to release EditDV - a 100% digital non-linear editor for $999. Rest assured, I will continue to keep you abreast of these exciting, important and potentially profitable developments.

For further information and pricing see the radius website at http://www.radius.com

This article first appeared as "John Henshall's Chip Shop" in "The Photographer" magazine, December 1997/January 1998.
This document is Copyright © 1998 John Henshall. All rights reserved.
This material may only be downloaded for personal non-commercial use. Please safeguard the future of online publishing by respecting this copyright and the rights of all other authors of material on the Internet.

Reports & Reviews indexHome