Exposure Compensation?

[ShaneS]

I think I have stumbled onto an answer to my problem but wanted to run it by the wise folks here to make sure that I got it right...

So, I was out shooting with my D7000 and my 50mm prime lens in harsh light the other day. White buildings and skies were blowing out like crazy so I set a negative exposure compensation of -.7 which still left me with a few blown highlights that I rightly suspected I could recover in PP.

Here is where the problem creeps in...when I pulled the images into ACR a lot of the images were flat but then when I boosted contrast and brightness they got noisy and really lacked clarity and punch. So, I started again and tried auto WB and I also selected auto for all of the other main adjustments. Turns out that in almost every case ACR wanted to boost the exposure and decrease the brightness in what I can only guess was counteracting my -.7 exposure compensation (highlights were handled much better though). The images still have a grainy look to them at 100% magnification and still didn't look right to me.

So I guess my question is twofold:

1. Is my assumption above correct? I think that the camera exposed more for the bright bits (at my construction) but that left the subject underexposed.
2. Is there a better way to handling harsh light at the point of taking the shot?
3. I always strive to avoid blown highlights but I think that in some instances it doesn't matter as much (street photography maybe?) - what is your position on that?

Thanks in advance

[HaseebM]

Sample of before and after? Maybe take two images and then merge them, just a thought.

[Mike Buckley]

If I understand you correctly, the dynamic range of the scene exceeded the range the sensor was able to record. Thus, at least some highlights and shadows were clipped. There's not a lot you can do about that when making just one capture of the scene.

I don't use ACR, so I have no idea how it was dealing with the situation.

[DanK]

Is my assumption above correct? I think that the camera exposed more for the bright bits (at my construction) but that left the subject underexposed.

If I understand correctly, you had an image that exceeded the dynamic range of the camera, so you imposed an extreme exposure compensation to darken the image and leave less of the image blown out. If that is correct, then the darker areas will be underexposed, and they will be noisy once brightened.

You can't increase dynamic range with exposure compensation. You could take multiple images and blend with exposure fusion or HGDR.

[Dave Humphries]

Hi Dan, Shane,

Dan, I'm not sure I'd call -0.7 stop "extreme exposure compensation"

However, I'm sure you're on the right track with DR (also Mike).

Shane. You haven't said what iso was in use?

Plus it would, of course, be useful to see what we're discussing.

Cheers, Dave

[ShaneS]

I believe I was using ISO 100 and/or 200. This is exactly what I was running into:

then the darker areas will be underexposed, and they will be noisy once brightened.
You can't increase dynamic range with exposure compensation. You could take multiple images and blend with exposure fusion or HGDR.

I was making a first reasonably serious attempt at street photography at the encouragement of a friend. Digital is cheap so I thought why not? Given that this was handheld street photography two exposures and blending later was not really an option.

So, that leaves my last question...in street photography where it is more about the people and less about the background is there an acceptable level of blown highlights?

I'm at work now but will post some examples from the day when I get home...

Thank you for the insights so far though and for giving my issue a name (DR)

[ajohnw]

I haven't got mine with me but vaguely remember an option to select 12 or 14 bit raw off the sensor. I'd suggest using 14.

Also what metering mode were you using? I would suggest evaluation but there is need to take account of the fact that if you have an object taking up a significant amount of a scene the metering will be biased by what ever shade it has. There have been many comments about Nikon cameras tending to over expose - from memory the D7000 was the first that doesn't. I'm not so sure. I find mine is ok on say scene type shots where an average type reading is ok but not so good under more mixed situations. Compensation requires a certain amount of clairvoyance - experience using the camera really. You should be able to recover a dark areas at the level of ISO you are using without much of a problem - maybe not if the analogue to digital converter is set 12 rather than 14.

John
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[DanK]

Dan, I'm not sure I'd call -0.7 stop "extreme exposure compensation"

oops. I read it as -7.0. should have thought.

[Shadowman]

I believe I was using ISO 100 and/or 200. This is exactly what I was running into:



I was making a first reasonably serious attempt at street photography at the encouragement of a friend. Digital is cheap so I thought why not? Given that this was handheld street photography two exposures and blending later was not really an option.

So, that leaves my last question...in street photography where it is more about the people and less about the background is there an acceptable level of blown highlights?

I'm at work now but will post some examples from the day when I get home...

Thank you for the insights so far though and for giving my issue a name (DR)

With street photography it depends on the actual subject. If you are shooting combination people and buildings, which would you prefer to be dominate or would you want both? If only a building and it includes glass or metal, how distracting would the blown highlights be, could the blown highlights (slightly of course) be an attractive element of the shot? If shooting mainly people as the main subject, street photography is forgiving of slight exposure problems, the final quality depends solely on you. Typically when I am shooting in direct sunlight, I try to position myself at different angles to the sun, whichever benefits my composition. In midday conditions it's totally acceptable to let your shadows go black and expose solely for the highlights.

[Polar01]

Shane you only increased the shutter speed 2/3rds of a stop that is not vey much. I have found that when you get the blinkies on the view screen you are still pretty safe because when you open in ARC and check the warning on the histogram guess what no problem. I have been shooting a lot lately 1.3 to 2 stops slower and able to recover in ACR. Now as you image is very bright I would suggest you press and hold "Alt" and move the black slider to stretch the histogram out to the left, when you see some dark blue appear stop. Once finished in ACR at some point in Photoshop add a curves layer and set a black point. The eye wants a good black to reference the white what you have here is a bright flat image that is lacking a good back in my opinion, as I have not seen the image.

Cheers: Allan

[dje]

Shane I think with this sort of difficult lighting situation, it's about compromise and getting the most important part of the image right. This may mean you have some blown highlight areas but if they are in areas of the image that don't matter much than it's not a problem. Similarly with noise in shadow areas, you may have to tolerate some noise in some parts of the image.

Some observations

Shoot with as low an ISO as possible, consistent with getting suitable aperture and SS settings. This will ensure the best noise performance.

Get to know how much exposure margin you have with your camera when shooting raw, in terms of highlight blinkies and what can be recovered in raw processing. Also bear in mind that even though you are shooting raw, the in camera review image is based on a jpeg produced in camera and the Picture Control settings (including Active D Lighting) will have an effect on when the blinkies appear and what the histogram shows.

Try to minimize under-exposure of the most important parts of the image.

Dave

[ajohnw]

I suspect having read some of the more recent comments there is a need to see the shots that were taken. Like most the D7000 should have getting on for 2 stops extra available for highlights in raw but I feel Nikon's metering can limit that but realistically there should still be around 1 1/2 stops. There is plenty of scope for recovering the dark end but as always decision need to be made about where and how dynamic range will be compressed in the final shot. Normally the aim is to not clip highlights at all as far as raw is concerned and rely on PP to recover any dark areas.

Need to see the shots but I suspect this is mostly a PP problem subject to the bit depth from raw. There is a chance that the camera has been pointed at something it just can't cope with but as Shane has taken shots before I suspect that is doubtful.

John
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[Polar01]

John I would suggest that you take a look at a article in The Luminous Landscape on "The Optimun Digital Exposure". It talks about the optimum exposure of an image which may not be the final exposure after processing in a raw converter.
I would suggest that everyone take a look at the article, been trying it now for a couple of weeks and am impressed with the amount of data that can be brought back from the high lights.

http://www.luminous-landscape.com/es...exposure.shtml

Cheers: Allan

[ShaneS]

Guys in Pink...shot at f5.6 ISO200 1/640 EC -.67 with my 50mm 1.8 prime

Straight into ACR as shot and then resized for presentation here (default settings):



Here is 100 % screen shot (note the noise):



Auto settings in ACR (no further adjustments - note minimal blown highlights)



And 100% of same (nose not really improved or worse):



As I was driving home I wondered if this could also have been caused by the auto focus not catching due to the fact that the subjects were moving towards me.

I'm stumped and I really appreciate the help.

[AB26]

Shane,

Nothing wrong with exposure. Can’t see the noise either.

What you got wrong here is focus!

In your 100% crop, look at the face of the man and then look at the lamp post to his right. Your focal point was in the wrong place. You can bump up the ISO (on a D7000) and shoot at a smaller aperture, like F9. The alternative is to use AF-C and keep your focal point on the subject you wish to be in focus.

Sharpening the image will solve your problem.

[Mike Buckley]

In this last set of three images, I think you somehow missed your focus point; the green pole is sharper than the people and surely their lack of sharpness isn't motion blur, not at 1/640 with them walking straight toward the camera.

I don't see any noise in the 100% version. Even if there is noise at 100%, I personally wouldn't care unless I was printing at a size that would expose the noise when viewing the image at a reasonable viewing distance. I doubt that would happen at a reasonable viewing distance.

[dje]

Shane if you want to boost the exposure of this shot, I suggest you do it in Photoshop rather than ACR. The men's outfits are quite bright and are a very dominant part of the image. So I would increase the exposure on the whole image a small amount and then I would create a layer mask which masks out their outfits and adjust Exposure on the rest of the image. You might need to fiddle a bit with Shadows and Highlights too.

And yes some more sharpening.

A quick and dirty attempt.

Dave

[Shadowman]

Agree with the others, the highlights are easily fixed and the shadow indicator shows that clipping would be in only one area, how large or visible would require closer scrutiny. As this is in your opinion "street photography" some leniency on quality is given from most viewers and practitioners, I try to get focus right but it doesn't always work out. Getting the focus right depends on how you are shooting, if you are shooting from the hip, or while you are in motion then getting focus tack sharp is going to be hit or miss. If you are stationary and only your subject is moving; then having a camera with a good focusing system, along with the countering for the motion you take to bring the camera into position has to be considered. What was your style when taking this photograph?

[ajohnw]

I;m on a poor monitor at the moment and would 2nd Mike's comments and add that the ACR views are a touch bright but that could be down to the screen I am using. There is plenty of detail in the whites which is good. Where you using continuous AF and keeping an eye on what the camera was actually focusing on? A zoom might be a better option as it would allow you to frame as you want and then open up the view to get the AF point where it needs to be. Personally I would forget about framing, focus in the correct place and crop during PP.

I can only guess about what ACR's sliders do but I suspect a little bit of the one marked recovery will get rid of the slightly blown highlights. Dropping off the exposure compensation,contrast or even brightness it's applied might too. I have to disappear but maybe some one else can run through how the sliders on that panel should be adjusted and in what order and how they inter react.

John
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[ShaneS]

You guys nailed it! I have the camera set to AF-S not AF-C and my focus point was off which compounded my exposure issue

I usually avoid shooting things that move and didn't even think of switching the focus mode - lesson officially learned

John...why the quotations?

As this is in your opinion "street photography" some leniency on quality is given from most viewers and practitioners

Wouldn't you call this street photography?

I went out today and did some tests with different metering modes for different scenes as well (no moving subjects) as I want to nail down how that impacts the image and also get a better understanding on how my camera handles the highlights. So all and all a great conversation and I appreciate each of you for your kind suggestions and guidance.