Exposure Recovery

[mikeadams]

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While sitting on the ground this morning in San Francisco to take a picture of a friend, I shot one, auto exposure, and it saw too much sky. As is my practice, I shaded the top of the lens with my hand, pointed down at his legs and locked exposure, re-framed and shot again. I put both into CS3 raw and tried to recover. I'm posting it for anyone who is interested.

 

http://www.trft.org/adamstestsite/exposuretest.html

 

Mike

http://www.mikeadams.org

[carstenw]

Interesting result. If you don't blow the subject, then exposing more is always better. It is heavily subject-dependent though, and it is a dangerous approach in general, because blown highlights are not recoverable. At what ISO did you shoot?

[farnz]

Mike,

 

I'd suggest exposing for the highlights (in this instance the sky) and pulling up the shadows as needed using the Shadows and Highlights tool. I notice for example that in image 2 the shadow recovery has produced visible chrominance noise under the brim of the hat, which I think might be avoided with S&H.

 

For interest, Lightroom has some useful features that cope with the M8's available shadow recovery very well.

 

Pete.

[mikeadams]

ISO 320, 35 f2 ASPH. I am using lightroom more and more, and I like its Web Photo gallery, and I am experimenting with it:

 

http://www.trft.org/MikesPhotos/mike2.html

 

Mike

http://www.mikeadams.org

[Artichoke]

which at times can be a good thing

for this matter I think standard practice has its virtues

in the sample you posted the sky has very little detail, which may be a consequence of your exposure or it is more likely took this under a grey, featureless sky

if that was the case, this may explain why you got these results

in your fourth sample the sky has lost all detail, showing the problem common when exposing for shadows ...this may not be all that important for this particular circumstance, as the sky here is featureless, but shooting for the shadows will loose all highlight detail and blow the sky as was the case in your fourth image

additionally, I find Adobe's RAW conversion not as good as Capture One that came bundled with the M8

while many find the Capture One interface annoying, the M8's DNG files were designed to work with it & it does seem to produce the best conversion for the M8's files

also shooting at ISO 320 gives less room for manipulation in post ...files will break up with noise faster as you make the sensor more sensitive (ie increase the ISO)

I do not think your samples support your hypothesis ...in the fourth example there is plenty of highlight lost completely as the sky is hopelessly blown

in such a challenging circumstance (dark subject against a bright background) you need to either 1) dual convert from RAW 2) use some fill flash 3) get a Fujifilm S3/S5 will has more dynamic range than the M8 from its uniquely designed sensor

nice gallery, btw

[mikeadams]

You are correct, no highlight detail, a featureless sky, actually rain yesterday in San Francisco. But I am impressed with the highlight recovery in both CS3 Raw and LR, and while it does not bring back the "dead" it does take away some of the brightness surrounding the blown highlights.

 

I did try Capture but I didn't like it. I usually take several dozen photos a day, and I do like being able to quickly sort in Bridge and open in batch in CS3 Raw.

 

Mike

http://www.mikeadams.org

[robertwright]

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I'd have to agree with artichoke, the M8 seems to me to be more like slide film than neg film in terms of exposure strategy.

 

Another point I wanted to make is to NOT accept the defaults of any of the raw converters-in particular Lr, it is pretty aggressive with contrast and black point-these values open as contrast +25 and Blacks +5 (clipping)- how this applies to exposure strategy-If you are exposing for the highlights and dragging the shadows up in post as I believe is best on the M8-you start out with a very dark image, the first move I make now is to reduce the black clipping to +1 and also reduce the contrast to zero or even less, a minus value-this has the effect of adding "brightness" without adding brightness, and consequently noise-the fill light slider also adds noise so I try to stay well away from it. Reason being, I have been shooting at twilight at iso 160 and coming back later to the images, all very dark, seemingly too dark, but do the above, and all this detail comes to "light" so to speak-it is like you are rearranging the tone curve-I find I need a lot less added exposure and brightness, which is where the noise comes in, I can dial in an additional +2 on the exposure and +100 on the brightness (max) at iso160, in effect making it iso 640 or a little more really, and all with none of the iso 640 noise. Try not to use the Black slider, use the shadow slider in the tone curve to gently compress the blacks, the Black slider is very aggressive in its clipping, the tone curve smoother.

 

In terms of absolute recover without noise, C1 will do the best job, so I save it for my high iso nightmares, or when I want absolute sharpness.