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Topic: RAW Recovery Function
Username: ptrjong
Posted 2013-01-10 14:56:42 and read 2662 times.

Hi all,

When working in RAW editors, I've always used the Exposure lever to treat (slightly) overexposed photos - it seems like the natural thing to do. But recently I've discovered the Recovery function in Camera Raw, and it seems to do a better job. Do you agree? Are there any snags?

Thanks,

Peter 

Topic: RE: RAW Recovery Function
Username: Silver1SWA
Posted 2013-01-10 15:34:30 and read 2650 times.

Quoting ptrjong (Thread starter):
When working in RAW editors, I've always used the Exposure lever to treat (slightly) overexposed photos - it seems like the natural thing to do. But recently I've discovered the Recovery function in Camera Raw, and it seems to do a better job. Do you agree? Are there any snags?

Recovery is indeed very powerful, but too much leaves a shot flat so a boost in contrast is often needed to compensate. It's a balance.

However, even more powerful is the latest ACR version in CS6. Instead of a "recovery" slider there is a highlight slider that is incredibly powerful, as well as a slider for whites.

Topic: RE: RAW Recovery Function
Username: ckw
Posted 2013-01-10 15:55:06 and read 2643 times.

It depends  

Basically as I understand it, exposure does pretty much what you would expect, reduces or increases the exposure.

Recovery, however, works differently - if an image appears overexposed, it may be only one or two channels which are blown. Recovery uses the data in the channels which aren't blown to recreate the 'blown' channels.

You can see the difference in the effect by watching the effect in the histogram display while moving the sliders. With exposure you'll notice very significant changes in the midtones, while the effect of recovery is pretty much expected to the highlights.

The best result will depend on exactly what the problem is. Often if the image is correctly exposed with just a few blown highlights, revovery does a good job. If the image is underexposed, then exposure may be the best tool.

But there are lots of different views on this. Some advocate fairly radical use of exposure (eg. up to -1.00) to pull back the highlights then use the brightness control to boost the midtones.

Cheers,

Colin

Topic: RE: RAW Recovery Function
Username: vikkyvik
Posted 2013-01-10 21:55:06 and read 2604 times.

I use Recovery rather sparingly. If I've gotten the exposure pretty close, then using the Exposure slider works just fine, even for slight overexposure.

If I've overexposed moderately, then I may use a combo of Exposure and Recovery. I'll do that to quiet down the highlights without darkening the midtones and shadows too much.

The other instance in which I'll use recovery is in photos where there is too large a spectrum for the camera to cover, and I didn't do an HDR for whatever reason. For example, if I'm shooting at dusk, I'll use Recovery to tame bright lights that are otherwise a bit distracting.

As Ryan said, though, using too much Recovery makes a photo look flat and very strange.

Topic: RE: RAW Recovery Function
Username: ckw
Posted 2013-01-11 01:22:00 and read 2582 times.

The key thing is to understand that blown highlights and over exposure are 2 different things.

If the dynamic range of the scene exceeds that of the sensor, it is possible to get the exposure spot on - ie. a neutral grey is correctly recorded, but still have the highlights appearing over exposed (or for that matter, shadows gone totally black). This is what "recovery" and "fill light" are for. They don't mess with the exposure (unless you use extreme values), but will attempt to build some detail in the blown highlights or black shadows.

As has been said, this can leave an image looking flat as effectively you are reducing the apparent dynmic range. After RAW processing I sometimes restore the image's "punch" by tweaking the tone curves. It can also look unnatural - remember the recovered detail is not "real" it is data interpolated from other channels - a typical result is solid bands of colour around the sun at sunset/sunrise instead of a smooth gradation,

If the midtones look overexposed, then the exposure slider is the way to go (though I find a combination of the exposure and brightness sliders works better).

Fill light works in a similar fashion to recovery - ie. it attempts to recover data from blocked up shadows. In general I don't think this works as well in so far as it invariably results in noisy shadows. This is because there is much less data to work with in the first place.

Cheers

Colin

Topic: RE: RAW Recovery Function
Username: ptrjong
Posted 2013-01-11 02:16:18 and read 2572 times.

Thanks guys. Especially Colin for another fine explanation.

Peter  


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