why meter when in RAW?

[BFocused]

RAW images contain more information and detail than traditional JPGs. Is it then possible to be lenient with your exposure metering and just relying on post processing the RAW to get the correct image? For example can you now not worry about correctly metering the snow using a gray card (or other means) and then just fix the gray snow in post processing?

[Xia_Ke]

Hi BFocused, welcome to PR While it is true that RAW files contain more info than JPG's, this just means that a RAW file will give you a little more leeway in editing. There is still no substitute for proper exposure. When shooting RAW, you still run the risk of loss of details in the highlights when overexposing ad loss of detail in the shadows if underexposing.

[Greg McCary]

You can certainly fix a lot when shooting RAW and have a good developing program like Lightroom. I have saved a few. But with that said I find things work much better if you just get it right in the field to begin with. I have really pushed myself to get as much right while shooting than hoping I can save it when I get home. I don't see much snow where I live so I can't comment on taking pictures of it. The total quality of the final image will be better if you nail it to begin with.

[AgingEyes]

Simply put, there is a limit on how much you can fix. And the fixed image may not look as good as the one that's done right in the first place.

[Medley]

Digital images record much more information in the light tones than they do in the darker tones. In any given image, 50% of the information in the image is in the lightest tone, 25% in the next lightest, 12.5% in the third, and so on down the line. These numbers reflect the information distribution before any edits or processing.

If you underexpose an image and lighten it, you're taking areas that don't have a lot of information to begin with and expanding them, spreading the information out even more. Dropping your subject down just one level in the dynamic range of the camera means that you lose half of the information, half of the detail, that would be contained in a correctly exposed image.

So, when shooting Raw, the object should be to OVERexpose the image as much as possible, but without blowing out (clipping) the brightest highlights. By doing so and darkening the result in post-processing, you take information from the brightest areas and push it down into the shadows, resulting in a much more even distribution of information. You'll see a big improvement in shadow detail, and I doubt you'll notice the change in the highlights.

But getting the image as bright as possible without clipping the highlights takes accurate metering, the ability to read a histogram, and a lot of practice.

- Joe U.