improving contrast with the local laplacian filter

sometimes difficult lighting situations arise which, when taking photographs, result in unappealing pictures. for instance very uniform lighting on a cloudy day may give dull results, while very contrasty illumination (such as back lit) may require to compress the …

Rawsamples.ch is a website with the goal to:

…provide RAW-Files of nearly all available Digitalcameras mainly to software-developers. [sic]

It was created by Jakob Rohrbach and had been running since March 2007, having amassed over 360 raw files in that time from various manufacturers and cameras. …

Have you ever over-exposed your images? Have you ever noticed that your images look flat and dull after you apply negative exposure compensation? Even though the over/underexposed warning says there is no overexposure? Have you ever wondered what is going on? Read on.

the problem

First, why would you want to know …

modern sensor capture an astonishing dynamic range, namely some sony sensors or canon with magic lantern’s dual iso feature.

this is in a range where the image has to be processed carefully to display it in pleasing ways on a monitor, let alone the limited dynamic range of print media.

example images

use graduated …

[update 2016/07/31: there was a section about intermediate export to csv and manually changing that file. this is no longer needed, exporting the style directly from darktable-chart is fine now.]

motivation

for raw photography there exist great presets for nice colour rendition:

• in-camera colour processing such …

Most modules in darktable are working on changing pixels color, lightness, etc. Few modules are moving pixels and when they do they are doing it in a very constraint way like to rotate, fix the lens’ distortions or remove spots.

The liquify module offer more ways to move pixels around by applying some free …

For many years darktable would only run on x86 CPUs that also support at least SSE2. While that is nowadays almost everything looking like a PC it’s still limiting. Consequently Roman sat down and started work on dropping that hard requirement. While his work isn’t complete yet it’s definitely …

Since many years darktable offers a versatile tool for manual perspective correction in the crop & rotate module [1]. Although the principle is simple and straightforward, there are cases where it can prove difficult to get a convincing correction, especially if no distinct vertical or horizontal features can …

Due to the heated debate lately, a short foreword:

We do not want to harass, insult or criticize anyone due to his or her choice of operating system. Still, from time to time we encounter comments from people accusing us of ignorance or even disrespect towards Windows users. If any of our statements can be …

If you overexpose a photo with your digital camera you are in trouble. That’s what most photography related textbooks tell you – and it’s true. So you better pay close attention to your camera’s metering while shooting. However, what to do when the “bad thing” happened and you got this one non-repeatable shot, …