• Removed user
    Feb. 12, 2024, 5:20 a.m.

    I'm no fan of Adobe. However their effort to provide an alternative to proprietary raw converters was at first seemingly laudable.

    But then along came RawDigger which allows one to examine raw data. To one's surprise and in spite of early Adobe-speak, DNG "raw" is not the same as what a camera writes to the card.

    compPauls.jpg

    compPauls.jpg

    JPG, 1.2 MB, uploaded by xpatUSA on Feb. 12, 2024.

  • edit

    Thread title has been changed from DNG versus raw.

  • Members 2111 posts
    Feb. 12, 2024, 5:49 a.m.

    I dont think any camera brand uses raw raw anymore. I think they are all manipulated by every manufacturer.

  • Removed user
    Feb. 12, 2024, 1:30 p.m.

    Agreed ... which is why I said "what a camera writes to the card" and which is why I examined raw histograms with RawDigger.

  • Members 300 posts
    Feb. 12, 2024, 1:57 p.m.

    Has it ever been that "raw raw" ? I think the "raw" has always been "what a camera writes". And what is the camera today? A computer with a lens and a sensor.

    Btw. Donald, do you know how do cameras manipulate raw files?

  • Members 511 posts
    Feb. 12, 2024, 4:07 p.m.

    Could it be a Foveon-only situation? I have never noticed a difference with Bayer raws.

    Could it be that the settings used are converting Foveon to differentiated RGB in the DNG, so that any DNG-capable converter can convert it without knowledge of the Foveon raw color situation?

    It would be nice if you could turn that off if it is the case, because converting to RGB makes for losses in monochrome conversions.

  • Removed user
    Feb. 12, 2024, 6:30 p.m.

    RawDigger does not confirm your thought, unfortunately.

    A lot can happen between the ADC output and the writing to the card.

    Examples for 12-bit ADC (0-4095):

    Nikon D50: 683 loss-less compressed

    Sigma SD9: around 9000

    Sigma DP2: around 3000

    Sorry, not sure what that means in context.

  • Members 293 posts
    Feb. 14, 2024, 10:34 p.m.

    It doesn't matter if the digital receive system is for audio, RF, or two dimensional such as in a camera, there is a host of processing prior to the recording. There is the amplification, signal conditioning, potentially companding in RF or power law gamma compression in imaging designed in to insure the voltage presented to the ADC falls in the appropriate range to get maximal dynamic range by insuring the signal range falls into the input range of the ADC. The ADC then quantizes the input data and coverts to a PCM digital output. The PCM data recorded in the case of an image is the raw collect or raw image. However, the signal into the ADC has had both linear and nonlinear operations applied to the output voltage of the photodetectors.

    In RF systems, designers often use AGC ( automatic gain control ) to insure the output voltage falls in the input required by the ADC. In digital imagery, it is a function of the person behind the camera properly setting the ISO. The equivalent in digital imagery to an AGC is auto-ISO.

    Rawdigger simply pulls the PCM samples. There is a lot that happens from the time the photons hit the detectors and the bits PCM samples hit the card.

  • Removed user
    Feb. 15, 2024, 2:25 a.m.

    Not on my camera. The Foveon channel output voltages are applied directly to the three ADC inputs..

    Nicely obfuscated. For some reason, I didn't know that "RF systems" have an ADC.

  • Members 293 posts
    Feb. 15, 2024, 1:35 p.m.

    Ever hear of a Software Defined Radio? Most RF receivers these days output digital data. The first thing done by an eNB in a cell network is to perform the appropriate tuning, filter in the RF, necessary signal conditioning, passing the signal off to an ADC and then digital processing used to extract the data from the signal. www.wirelessinnovation.org/assets/documents/SoftwareDefinedRadio.pdf
    dprevived.com/t/dng-versus-proprietary-raw/5550/

  • Removed user
    Feb. 15, 2024, 5:17 p.m.

    No.

    Unintelligible to most, if not all members, as usual.