The Unbearable Lightness of Mystic "Exposure" Triangle

We should begin by saying that the point of all of this is not just to criticize one of the most repeated photographic myths out there – that's just a tool, because an incorrect understanding of the way that exposure and ISO work, as well as their roles during the shooting process, leads to a falloff in the quality of shots that photographers get.

So our goal is to show how, by rejecting this myth, you (the now-enlightened user) will be able to more fully utilize the capabilities that your camera has, as well as to improve the quality of your photographs.

Barnum Quote vs Exposure Triangle

ISO is Seldom just a Digital Gain

RawDigger. Raw histogram. Digital ISO 25600

Some say, "exactly like dragging exposure slider in Lightroom, ISO ... is just digital gain".

With a few exceptions, this is less than a half-truth.

Though it is often the case that at higher ISO settings digital "gain" is applied (or a converter, using a metadata tag, is instructed to apply it), analog gain still acts first, before "digital gain" (the better word would be "multiplication", not gain, as in electronics "gain" most often pertains to analog domain).

The giveaway for multiplication is deep and regular gaps in the raw histogram that become wider with each increase of ISO setting.

A Curious Case of ISO Bracketing with Fujifilm X-series

Time for Standards, stockbakery

A few days ago, a FastRawViewer user turned to us with a question:

"I took a series of photos with ISO bracketing, but FastRawViewer shows them all in the same way on the main window, even though the JPEG previews are different. I think you have a bug!"

In answering him, we suggested several reasons as to why this is happening, among which was the option that "It's possible that your camera doesn't even do anything when the ISO is changed".

The user sent us the files, and the result was...exactly that; the automatic change of the ISO setting while bracketing didn't affect the RAW data at all.

New Old Approach to Dynamic Range

Michal Bednarek (Niserin)

In today's world, "dynamic range" (DR) has become, in the minds of (many) photographers one of the main characteristics of a digital camera.

Unfortunately, the public data on DR is limited to "DD - ISO sensitivity" graphs and tables. With this, the nature of noise (for example, random noise, banding) isn't accounted for, however the noise character is important for visual quality.

In reality, any practicing photographer knows that the degradation of the image in the shadows (or because of low exposure) happens gradually, there is no strict demarcating line. It's just that with the lowering of exposure, small details disappear, the contrast between bigger details diminishes, color fidelity becomes worse. Depending on the quality demanded of the image (which will depend on presentation size, viewing distance, other viewing conditions such as screen resolution, etc.,), the practical dynamic range for the specific camera will be different, even for the same ISO setting.

Monochrome2DNG - File Converter for «Monochrome-Converted» Cameras

Almost all digital cameras that are released today are color cameras. Nevertheless, there is demand for BW (Black and White) cameras because of reduced artifacts and higher resolution of resulting images. And many photographers want BW cameras with the same lens mount as their main (color) camera, so that they can use the lenses they already own.

Converting a color camera to BW is done by removing the CFA (Color Filter array). However, during such conversion, the firmware of the camera doesn’t change, and the camera doesn’t know that it’s become monochrome, which leads to several problems, which Monochrome2DNG - a file converter for «monochrome-converted» cameras - is going to address.

Monochrome2DNG Beta 0.8

RawDigger 1.2.24

RawDigger 1.2.24

What's new:

  • Camera support added:
  • Sony ARQ format support
  • Olympus E-PL9
  • Panasonic DC-GF10/DC-GF90, GH5S, GX9, TZ200/ZS200, G9 (in high-res mode).
  • Fujifilm X-A5, X-A10, X-H1
  • Exiftool updated to version 10.79
  • Bugs fixed: Sigma Quattro H 'AF points interpolation' was not interpolating last AF points row

DPRSplit (Beta) - File Splitter for Canon 5D Mark IV / Dual Pixel Raw files

Canon 5D Mark IV's sensor has a somewhat unusual pixel arrangement: each pixel is composed of two subpixels. If Dual Pixel RAW mode is enabled in the camera, the resulting CR2 file contains two images, or two frames: one composite, made from reading both subpixels, summed; and the other is made out of one set of subpixels.

In essence, in Dual Pixel Raw mode, the camera records into one file some equivalent of two shots, bracketed by (approximately) 1 EV.

The DPRSplit application is intended to extract this additional frame out of the CR2 taken in Dual Pixel RAW mode, and save it as a DNG. Resulting DNG files can then be opened and processed in (practically) any raw converter featuring DNG support.

DPRSplit Beta 0.8.2

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