Live View on a PC ?


If you are not so lucky as to have a camera that allows for tethered shooting with live view on a PC, you might still desire to have live view on a PC for various reasons. And that is indeed possible with many digital cameras.

It does require that the camera has a composite video - PC/AV terminal (almost any digital camera would have that) and further - and here you must consult your camera manual - that the live view video signal is available on that PC/AV terminal.

If you have that in place, you only need one additional piece of hardware together with the video cable that normally comes as part of the package with digital cameras (or is available as an optional extra).

    Figure 1
That special component is a so-called video grabber:


Figure 2: ´Deltaco "GrabBee deLuxe" video grabber   Figure 3: My Pentax K-5 with AV cable; GrabBee videograbber and Acer Aspire One notebook.
The video grabbers were originally designed for capture and digitizing of video from analogue video cameras and tape recorders; the analogue AV signal from the camera was/is intended for viewing of the movies and pictures stored in the camera on a television set. Jointly, they serve our purpose fine: To make the live view images of the camera LCD screen viewable on a PC - again, provided that the live view signal is accessible from the AV terminal on the camera.
The rest is simple and straightforward: Install the capture and display software that came with the video grabber on the PC; plug the USB connector into the PC and open the capture software; next plug the AV cable into the camera; connect the male terminals for video and sound of the camera cable to the corresponding female terminals of the video grabber and let the analogue-to-digital converter integrated in the video grabber cable do its job:

Figure 4: Pentax K-5 Live View on Acer Aspire One notebook
And voila, you've got live view on your PC. Now, the weakness of all this is that you only get VGA resolution (640 x 480 pixels) which is actually a far cry from the resolution you get today on most camera LCD screens (typically around 1 Mp for a modern DSLR). Nonetheless it is convenient for alignment and critical focusing in certain situations such as macro- and astro photography where the camera may be very inconveniently situated for manual focusing with the aid of the camera's LCD screen. And as can be seen in Figure 1 above and 5 below one can use a very small netbook to get a very portable "field rig" yet providing a sufficiently large image for easy alignment/composition and focusing.

Figure 5.a: Pentax K-5 Live View at 4X zoom. Screen dump from Acer Aspire One netbook;

(original image size is 1024 x 600 pixels)


Figure 5.b: Pentax K-5 Live View at 4X zoom. Actual frame capture with Deltaco "GrabBee deLuxe" video grabber; (image size 640 x 480 pixels)


As a final note, modern digital cameras tend to come with HDMI output terminals as well and there are USB/PC capture devices commercially available for digital HD video as well. However, they are still rather expensive; they require fast (USB 3 or Firewire) connections with much larger bandwidth and live view will normally only be accessible on the HDMI terminal when the camera is in video camera mode.


So, as for now I am content with my little, low-resolution but very compact and portable "field solution" described above.




Copyright © 2012 - Steen G. Bruun