• 09-04-2004, 07:16 AM
    piebald
    Brightness change after uploading pictures
    I have just bought a Canon Powershot S60. When I upload pictures to my computer the brightness of the pictures seems to consistantly decrease. Increasing the brightness by about 4% seems to rectify this.

    I don't want to have to keep adjusting the pictures or risk losing quality by resaving them. How do I tell whether the brightness change is due to jpg losses or whether it is my monitor/computer settings?

    :confused:

    Thanks. :)
  • 09-04-2004, 10:03 AM
    opus
    If you're comparing to the LCD monitor on the camera, that's more unreliable, I think. Do you have a histogram on your camera that you can reference?
  • 09-04-2004, 10:13 AM
    Trevor Ash
    Hi, it's your computer/monitor settings that are cause your images to "appear" brighter. In reality, they haven't changed brightness at all.
  • 09-04-2004, 03:01 PM
    Michael Fanelli
    Quote:
    Originally Posted by piebald
    I have just bought a Canon Powershot S60. When I upload pictures to my computer the brightness of the pictures seems to consistantly decrease. Increasing the brightness by about 4% seems to rectify this.

    I don't want to have to keep adjusting the pictures or risk losing quality by resaving them. How do I tell whether the brightness change is due to jpg losses or whether it is my monitor/computer settings?
    If you are judging brightness using the LCD, don't. LCDs are not designed for that, use the histogram.

    If you have not calibrated your monitor, you need to do that. Monitors are notoriously bad for photographs as non-photographic applications can't tell the difference between calibrated and non-calibrated. The simple calibration program that comes with PhotoShop is good enough for most purposes.
  • 09-05-2004, 11:55 AM
    piebald
    Quote:
    Originally Posted by Michael Fanelli
    If you are judging brightness using the LCD, don't. LCDs are not designed for that, use the histogram.

    If you have not calibrated your monitor, you need to do that. Monitors are notoriously bad for photographs as non-photographic applications can't tell the difference between calibrated and non-calibrated. The simple calibration program that comes with PhotoShop is good enough for most purposes.
    The histograms vary but a large number are biased towards the left. What does this mean exactly? I haven't got photoshop. Is there a free calibration tool somewhere?
  • 09-05-2004, 12:33 PM
    Michael Fanelli
    Quote:
    Originally Posted by piebald
    The histograms vary but a large number are biased towards the left. What does this mean exactly? I haven't got photoshop. Is there a free calibration tool somewhere?
    If your histograms are towards the left, they are probably too dark. A very good introduction to histograms can be found at:

    http://www.luminous-landscape.com/tu...stograms.shtml

    I don't know of any free calibration tools. Perhaps someone else here has some information for you about this.