AUTO – Nothing

To create the image that you want, not one like everyone else’s, you must be in control of the camera and not vice versa.

In the lessons on exposure, focus, and motion (shutter speed) we covered the basics. Also, we discussed how to go beyond the basics. In every instance, going beyond has meant taking control away from the camera – first and foremost by not using the camera’s Automatic Exposure mode but using one of the following exposure modes instead,

  • Aperture Priority
  • Shutter Priority
  • Manual
  • and further, when precise focusing is needed, Manual Focus.

Is that all of the ways for camera to automatically “help” us? No. Two very important functions have automatic options. If you insist on using them (don’t) at least be aware of their downside. They are –

  1. Auto- ISO
  2. Auto-WB (white balance)

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ISO – Changes to ISO result in two things-

  • 1. Change in shutter speed (higher ISO results in a faster shutter speed)
    • Raising ISO is desirable when opening the aperture isn’t appropriate because either
      • The aperture is already wide open, or
      • You need the DOF at the smaller aperture
  • 2. Increase in noise with increasing ISO
    • Raising ISO is undesirable because it introduces unwanted noise in the image
    • Lowering ISO is always desirable

Using Auto-ISO puts the camera in charge of both shutter speed and noise. You should do this advisedly – and not as a matter of routine. I allow my camera to use auto-ISO in only one situation – when I choose my self-designed saved preset, Action (action photos). In this case-

  • Shutter priority
  • 1/250s is my specified slowest allowable shutter speed
  • Auto-ISO makes ISO changes only when the aperture is wide open and that, by itself,  is inadequate to keep the speed faster than 1/250 sec.

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White Balance (WB) – I am dismayed at the number of times I’ve read “tips” that say to use auto-WB. Just as with ISO, there are times when it’s appropriate but, as a rule, you are better off by choosing a manual setting (such as Cloudy for outdoors – regardless of whether it’s actually cloudy). Some thoughts-

  • If you shoot RAW your WB setting, regardless of what it is, can be changed in post processing.
    • The downside is that you have to do this manually (or batch) for every image to fix your mistake
  • Here is the big problem with auto-WB
    • The light color outdoors changes constantly (literally second by second even though you can’t see it)
    • This means that the color (cast) on each of your images is different since “auto” is constantly “fixing it” for you
      • In auto-WB the light temperature is monitored constantly & “fixes” are made to the image – each “fix” different
      • With a manual WB setting, the same “fix” is applied to each image, thus a constant color rendition
    • If you used auto-WB and want the same color in every image made of a scene, good luck figuring out how to do this on an image by image basis (unless you shot in RAW)
    • This problem is seen easiest if you shoot certain color flowers (like a pink/magenta wild geranium, or a violet)
      • Take a dozen shots of the same flower over a period of 5-10 minutes using auto-WB
      • Load these images to your computer and compare the colors
      • Imagine what you’d do to make the colors all the same (again – easy in RAW)

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Here’s the final AUTO-never:  never shoot in anything other than RAW (unless you use a RAW+JPEG combo).

  • If you don’t use RAW, you’ve turned the entire process for converting your camera’s captured (RAW) image into a viewable and printable form over to the camera’s automation.
  • In general, there are many ways to do the RAW-to-JPEG conversion – each with different results.
    • However, in your specific camera there is one way and only one way.
    • That 1-way is the auto-process decided upon by your camera’s manufacturer.
    • Usually, the selected process works well but, when it doesn’t, there’s no turning back, no do-over’s, no mulligans, nada.
    • You get what the manufacturer decided was good and that’s it. You’ve just chosen – AUTO-CONVERSION – which may be the worst “AUTO” of all.
      • JPEG is the worst of the worst if the quality introduces undesirable artifacts due to compression
        • If you do use JPEG and not RAW at least use the highest quality (something like Extra-Fine)
        • The  TIFF format, if available, avoids the JPEG compression artifacts problem
        • Once shot & converted there is NO going back.
  • Event photographers (shooting thousands of images – weddings for example)
    • Sometimes use JPEG (after fine-tuning all of their camera settings and their processing workflow)
    • It’s a post-processing time constraint that leads to this (like offering prints on the spot)
    • If you’re not an event photographer, you don’t have a good excuse for skipping RAW

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Summary –

  • ISO – changes can’t be undone even in RAW
  • WB – changes can be undone in RAW; may or may not be fixed easily otherwise
  • Conversion – if you didn’t choose RAW you get whatever you got for better or worse