Open Source Photography

Articles and tutorials on digital photography in an open source environment: color management, raw processing, camera and monitor profiling, bug reports and some other stuff, too.

Recent and recently revised articles:

1. sRGB, the universal monitor profile, not so good for LCD monitors

   LCDs and CRTs — color-wise, they are very different beasts. If you are using sRGB as your LCD monitor profile, you might want to reconsider: sRGB was designed for use with CRT monitors. If you have an LCD monitor, sRGB is not likely to be a good enough match [...]

2. digiKam/showFoto Settings for Color Management: Behavior Tab

   digiKam/showFoto 'Settings for Color Management', Behavior Tab, asks the same questions that any good color-managed software will ask: what working space to use, what to do when an image profile doesn't match the working space, and what to do with untagged images.

   Although this article specifically addresses the digiKam/showFoto 'Color Management Settings', after reading this article, you'll be able to make the right choices for any properly color-managed imaging software [...]

3. UFRaw highlights problem

   Sometimes UFRaw creates areas of blown highlights in an image, when the raw file itself doesn't have any blown pixels. The first image is the red channel after processing with UFRaw. The second image is the red channel after processing with dcraw. Note the complete lack of detail in the UFRaw red channel in the brightest areas of the flower petals (circled in red). In stark contrast to the UFRaw output, the dcraw red channel shows full detail in the red channel highlights [...]

Featured Articles:

1. The history behind the very odd sRGB color space

   In the early 1990s, digital images were being produced on all kinds of hardware, using all kinds of software, with and without embedded color space information, that might or might not be interpretable by someone else's hardware and software. It was only by the wildest of coincidences if the consumer of a digital image saw anything close to what the producer of that digital image actually intended.

   It was the wild, wild west of digital color management, and the need for a sheriff to move in and establish order was obvious to everyone. In 1996, Hewlett-Packard and MicroSoft took on the role of color management sheriff [...]

2. All the Colors, Some of the Colors, the Colors of Daylight

   What's that funny horseshoe thing? It's all the colors in the world. . . . You use color space profiles every day in your digital darkroom. If you'd like to know more about what a color space profile is, read on . . . Our specimen color space profile will be the ubiquitous and historically interesting sRGB [...]

3. Profiling Your Monitor — popular confusions, hopefully cleared

   Alas, digiKam and Krita have already made it so that if you install a system monitor profile, you no longer have a choice of which monitor profile you want to use for editing until you UNinstall the system monitor profile.

   If you are not really sure what the difference is between calibrating and profiling a monitor; if you've heard the words "vcgt tag" but don't know what it means; or if you'd like to know what a system monitor profile is, this article is a place to start.

   If you are a software developer and you mistakenly think that making and using more than one monitor profile is just plain stupid (the esteemed Bruce Fraser would have disagreed with you), then by all means, please read this article [...]

See Articles on Photography for links to and descriptions of all the photography articles on this website.