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I regularly take RAW outdoor photos, and I encounter a annoying problem on post processing: on photos containing grass with both shadows and areas with direct sunlight, I can't recover blown out areas without them turning to posterized beige areas.

Example of a processed photo with posterized beige area

It seems that these areas are beige because the saturated imaging sensor shifts the grass green shades to beige shades. Do some photographs here know

  1. how to process such photos to recover blown out grass areas while restoring the tint to green instead of beige, or
  2. how I should take these photos to prevent blown out areas enough to make this recovering useless, or
  3. if I should stop bothering with blown out areas and darken them just enough to prevent them from burning viewer retinas while keeping them bright enough to prevent the tint shifting becoming too visible?
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The high dynamic range is problematic for cameras (the human eye can handle more, so it seems fine when you look at it).

Aside from the option of expensive professional cameras (which give a bit more dynamic range - there is a reason for the price), you can

  • reduce exposure during the shot, so that the brightest areas do not get washed out. This will result in the shot looking too dark at first, but that is easy to correct in post processing. Of course, there is a limit for that too. I would try to set the exposure correction to -1 or -2 for a try. Worst case, the darkest areas start showing color noise in the processing, but with ISO 100 that's a long way to go.
  • HDR (high dynamic range) is certainly a solution, but requires some more processing, and either a camera that supports it, or a tripod and very unmoving subjects. Take three or even five shots over a wide range of exposure adjustments, like -4/-1/+2, or -6/-4/-2/0/+2, and combine them in LR or similar. HDRs can look unnatural if the processing is overdone, but contrary to many people's thinking, this is not implicit of HDR - it is a choice in the processing. A well done HDR looks perfectly natural.
  • the simplest way (and probably the poorest result, but the only option after the fact) is to correct the color of the blown out grass, by either selecting the color you want and then mono-chroming it and bleeding the target color into it (could look unnatural), or cloning the good-looking grass slowly over all the blown out grass - depending on the amount and form, this could work very well, or very poor.
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To me, there are three different levels of abstraction in the question:

  1. 'Blown out' concerns a technical abstraction related to dynamic range. 'Brown' concerns a similar technical abstraction related to gamut.
  2. 'Highlight' concerns a pictorial abstraction similar to subject, background, and foreground.
  3. 'Grass' and 'sunlight' concern the semantic context of the photograph.

Technical Domain Analysis

Reading the question, one of the first 'solutions' for 'saving the image' was to convert it to monochrome since I often find it a useful way to bypass problems related to the lack of ordered color in the real world.

monochrome image of sitting person with dog in shade

Pictorial Analysis

The monochrome version shows high contrast between the human head and the sunlit grass in the background. This might be why this particular vantage point might have caught the photographer's eye and suggests that the bright background is a compositionally strengthens the image.

Semantic Analysis

The photograph is a picture of a person and a dog. It is not a picture of grass or sunlight on the grass. One way of 'saving the photograph' is to improve the semantic domain via cropping the image to remove extraneous elements as shown:

cropped image of sitting person with dog in shade

Pictorially, the crop removes grass from the foreground and restricts green to the middle ground. The 'blown highlight' becomes more like one giant bokeh. Gone are legs and and paws and several dog hind quarters.

Caveat

In ignoring the question of whether grass should be green I am probably taking a position a bit contra to realism as the primary aesthetic of photography. It's probably a natural result of looking to monochrome first when seeking a 'solution.' There are other legitimate views on photographic aesthetics and hence, your mileage may vary.

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how to process such photos to recover blown out grass areas while restoring the tint to green instead of beige

Some raw developers may be better than others in restoring details/color. If you run into this situation frequently, consider testing several of the leading raw converters to see if any gives more pleasant results. My top candidates would be DxO, C1, Adobe Lightroom/ACR. Eisman and Margulis describe some advanced Photoshop techniques for this kind of restoration in their books, if you are inclined to work with channel masks, Lab and other things.

how I should take these photos to prevent blown out areas enough to make this recovering useless

If the shadow area is small, you can equalize the contrast with flash. Larger areas can be lit with collapsible reflector like Lastolite. You can also try avoiding these shooting conditions altogether. Watch your RGB histogram. If any channel is blown out, reshoot with some negative exposure correction.

Higher bit and uncompressed raw files are usually better at this than lower bit and compressed. Make sure you are not using any crippled raw format derivative.

if I should stop bothering with blown out areas and darken them just enough to prevent them from burning viewer retinas while keeping them bright enough to prevent the tint shifting becoming too visible?

This reminds me of Hollywood movies. The directors of photography never make/show mistakes like that - unless it's an intention. They know what the camera sensor or the film stock can handle and accommodate the shooting conditions appropriately. They sometimes use abnormal measures not suitable for amateur still photography, but the picture quality they provide is a good inspiration.

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This is a symptom of the green sensors being blown. Once a sensor cell gets to 100%, anything additional is lost, same way you would lose a good portion of, say, a quart of milk if you tried to pour it all into a 8 oz glass. You could try reducing red and blue, but as the color of grass is a mix of the 3 colors and this will not reclaim the right proportions. Raw doesn't help you because the information just isn't there Outdoors, green blows out first. Cheapest solution (other than using fill flash going down 1 or 2 stops) is a magenta filter. There's a lot of green light out there, this gets it down closer to R and B levels - at the cost of changing your WB. Use a grey card (and maybe check out uniWB)

For setting exposure for scenes with a lot of dynamic range, check out the digital zone system http://www.outdoorphotographer.com/tips-techniques/nature-landscapes/the-digital-zone-system/

TLDR: 'RAW' doesn't help when sensors are overloaded - which they are here

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