Controlling digital SLR cameras with gPhoto2

Applications

GPhoto2 is ideal for making a series of shots. This applies to time-lapse photography as well as to astronomical single shots that you later combine as a sequence.

A good example of a time-lapse application of gPhoto2, including the resulting video, can be found in mathematician and photo hobbyist David Clark's blog [3].

A rather painful restriction applied to the Nikon camera I used in my test. Nikon doesn't support so-called bulb mode for long-term exposures that you can invoke in gPhoto2 with the -B or --bulb parameters. Using bulb mode with the Nikon D70 or D5100 resulted in an error message informing me that long-term exposures were not supported.

The gPhoto2 programmers are clearly not supported enough by the camera manufacturers. Apparently, Canon DSLR cameras don't have the same trouble [4], but I couldn't check that myself.

Conclusion

The powerful gPhoto2 software significantly unburdens the photographer from long continuous shooting. Taking astronomical photos with many hours of exposure time divided into 30-second intervals can be a cinch.

Live View mode of the newest DSLRs provides an easy and reliable sharpness control on the PC, on a screen much larger than that of the camera. You can have the PC monitor take over the poor visibility positions, such as you would get on a telescope.

The integration of gPhoto2 with Darktable, Gtkam, and GIMP provides a relatively easy working relationship. Unfortunately, only Darktable supports tethering and has a convenient GUI for remotely controlling series shots.

Darktable, although a powerful tool, has a relatively steep learning curve, so if you value stability during photo shoots, it's probably best to stay with gPhoto2 and its command-line operation.

The Author

Karl Sarnow has been a fan of personal computers since his TRS-80 Model 1. A teacher of mathematics, physics, and computer science early in his career, he created networking concepts for Linux and corresponding applications for schools and training. Since his retirement, he has been devoted to his hobbies of photography, travel, and astronomy.