Archives for 2013

There’s an oft-told line about how the Apple II made its way into businesses in the late 1970s and early 1980s. Thousands of businessmen walked into computer stores and said. “Sell me a copy of Visicalc and something to run it on.” I just bought a Mac. It’s been more than ten years since I… [Read More]

For the couple of weeks, I have been spending way too much time trying to develop a way to demosaic infrared raw files without interpolation. My reasoning is that, with a deep IR filter in front of the sensor, that the spectral response of each of the color filter array (CFA) planes is pretty close… [Read More]

I was unable to figure out why Lightroom is boosting the brightness and chroma of 32-bit floating point TIFFs imported into it, so I reluctantly decided to use the correctly-exposed synthetic image with the minus one-stop Lightroom Exposure adjustment as the reference and compute errors from it. I computed the CIEL*a*b* Delta-E stats of the… [Read More]

Eric Chan has informed me that there are two image-processing pipelines in Lightroom: output-referred, and scene-referred. Raw files get the scene-referred pipeline. Integer TIFFs get the output-referred pipeline. Therefore, all my TIFF test images were getting a different set of processing than LR applies to raw files. I’ve done some testing with real raw files,… [Read More]