• Members 2303 posts
    April 27, 2023, 9:20 p.m.

    Shooting events with my sony a74, jpegs are first class. saves me time on low cost event shoots and I can actually make money. you make money in the field not sitting behind a computer.

  • Members 2303 posts
    April 27, 2023, 9:25 p.m.

    i suppose Santa Christmas photos taken on mass and printed within an hour at major shopping malls is not professional in your eyes 🙄

  • April 27, 2023, 9:30 p.m.

    Donald - be nice to people. Their interpretation of professional may be different from yours.

    Alan

  • April 27, 2023, 9:31 p.m.

    How about this diagram to explain where different camera parameters are used. Feel free to tell me I am wrong (in the nicest possible way 😁)

    light flow.jpg

    light flow.jpg

    JPG, 78.6 KB, uploaded by AlanSh on April 27, 2023.

  • Members 2303 posts
    April 27, 2023, 9:33 p.m.

    Please define.

  • Members 2303 posts
    April 27, 2023, 9:37 p.m.

    Exposure triangle is set before you even take the image not after 😁

  • Members 533 posts
    April 27, 2023, 9:37 p.m.

    Not really. If the camera was choosing Av or Tv values based on metering, set to ISO 4000, then you have more read noise and more photon noise relative to exposure, than if you had the camera set to ISO 2000. A case where you would have less read noise at ISO 4000 would be where your exposure was standard for ISO 2000, but you had the camera set to ISO 4000.

  • April 27, 2023, 9:41 p.m.

    My diagram is intended to show that the ISO adjustment happens after the light hits the sensor but before it gets stored on the SD card. It cannot happen before the light hits the sensor.

    Alan

  • Members 2303 posts
    April 27, 2023, 9:45 p.m.

    goes both ways , be nice. "But in neither case would be considered 'professional' if photography were a chartered profession"

  • Members 1737 posts
    April 27, 2023, 9:47 p.m.

    et diagram.png

    1) Lens can't put more light on the sensor than came in through the front element. Maybe you mean something else.
    2) Some part of the ISO adjustments can occur before the signals are turned into voltages.
    3) I have no idea what this means.

    It's a pretty diagram. You have elided the conversion to digital. Maybe that was by design.

    Jim

    et diagram.png

    PNG, 522.0 KB, uploaded by JimKasson on April 27, 2023.

  • Members 457 posts
    April 27, 2023, 9:50 p.m.

    I apologize, I should not have judged you and your work.

  • Members 533 posts
    April 27, 2023, 9:57 p.m.

    Yes, I over-did my trimming. Not enough context left.

    I was referring to the fact that "Live View" is not synonymous with "silent shutter" as @DannoLeftForums seems to have implied. EFCS is what I believe my first DSLRs with Live View had, and it wasn't until later that e-shutter was available for Live View. It may be that rolling shutters were too slow in the early days of LV to make e-shutter desirable.

  • April 27, 2023, 9:58 p.m.
    1. I agree. I meant to say 'same or less' - and in reality it must be less as the lens itself will reduce it even at the widest aperture.
    2. But it's always after the light hits the sensor - no matter where after the light hits it. So, I agree with you, but my diagram is meant to show that ISO adjustment doesn't happen before the light hits the sensor and is turned into some sort of electronic signal.
    3. It's meant to show that the "exposure triangle" concept takes place before the data is stored on the SD card - so ISO does have an effect on the end result - bit not on the light itself.

    Does that make sense or have I oversimplified it (or just plan got it wrong)?

    ALan

  • Members 1737 posts
    April 27, 2023, 9:59 p.m.

    In 1959, I was working for a school newspaper photographing a cross country race some distance from the school I went to, and even further from New Haven, CT, where the paper was printed. I made some images with a 4x5 Speed Graphic, and took the film holders to a regular newspaper office near where the meet was being held. I used their darkroom to soup the negs, printed one of them wet, rinsed off most of the fixer, and dried it face down on a flash drier they had that took about a minute to dry the print. Then one of the paper photographers put the print in a kind of drum scanner and sent a facsimile to the printer in New Haven, who made a plate, put it into the rest of the frame together with an article a friend phoned in, and we had printed copies of the newspaper at the school before we got back from the meet.

    I had never heard of a fax machine, and I don't think they called it by that name. It was something the newspapers used to communicate with the wire services like AP and UPI.

  • Members 1737 posts
    April 27, 2023, 10:02 p.m.

    You are right about after the light hits the sensor, but there are changes that the ISO control causes in dual conversion gain sensors that occur before there's a voltage describing the charge on the capacitor. Maybe you are saying that the charge itself is some kind of electronic signal, but I think that's a stretch.

  • Members 1737 posts
    April 27, 2023, 10:05 p.m.

    If you buy into the ET concept in the first place, the concept influences the photograph before the image is exposed. And not always does the ISO affect the data written to the flash card. Usually, but not always. There are so many different implementations that it's really hard to cover all of them with one diagram.

  • Members 2303 posts
    April 27, 2023, 10:06 p.m.

    the problem occurs if you don't separate photo diode to sensor. the sensor as a whole component integrates amplification circuits, within that iso/gain controls are part of that assembly. eg dual gain circuits. and dare to say even normal iso control.

  • Members 1737 posts
    April 27, 2023, 10:06 p.m.

    I wouldn't call it plain wrong. There are cameras that work the way you've diagrammed, but fewer and fewer of them, these days.